US2806186A - Relay adjusting set - Google Patents

Relay adjusting set Download PDF

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Publication number
US2806186A
US2806186A US418412A US41841254A US2806186A US 2806186 A US2806186 A US 2806186A US 418412 A US418412 A US 418412A US 41841254 A US41841254 A US 41841254A US 2806186 A US2806186 A US 2806186A
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United States
Prior art keywords
relay
contact
current
armature
demagnetizing
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US418412A
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English (en)
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John T L Brown
Jr Charles E Pollard
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AT&T Corp
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Bell Telephone Laboratories Inc
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Priority to US418412A priority Critical patent/US2806186A/en
Priority to DEW16193A priority patent/DE952289C/de
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/327—Testing of circuit interrupters, switches or circuit-breakers
    • G01R31/3277—Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches
    • G01R31/3278—Testing of circuit interrupters, switches or circuit-breakers of low voltage devices, e.g. domestic or industrial devices, such as motor protections, relays, rotation switches of relays, solenoids or reed switches

Definitions

  • FIG. 6 FIG. 7
  • This invention relates generally to relay test circuits and more particularly to a test set for automatically testing and adjusting the permanent magnet bias of polar relays having permanent magnet polarization or bias affecting the armature movement thereof in addition to the usual energizing means such as a coil or coils.
  • the present invention relates to a circuit for automatically adjusting the permanent magnet 'bias of a relay which includes an energizing winding and at least one contact and a permanent magnet and a magnetic armature movable in operable relation to said contact under the influence of the combination of the magnetic field produced by energization of said winding and the magnetic field of said magnet.
  • An object of the invention is to improve the art of adjusting such relays.
  • a particular object of the invention is to improve the means whereby the adjustments of interest are made to a polar relay of the totally enclosed type, which, due to its sealed construction, precludes the usual manual adjustment familiar to the art.
  • Patent 2,590,228 to J. T. L. Brown of March 25, 1952 This method is described therein as used, by way of example, to adjust the magnetic bias of a polar relay of the sealed, mercury type, such as is shown in Patent 2,609,464 to J. T. L. Brown and C. E. Pollard, Jr. of September 2, 1952, and which has a movable armature arranged to make contact with either of two contacts and all sealed in a glass envelope containing mercury fed by capillary action to the contact areas and which has a permanent magnet attached to each contact outside of the envelope and an energizing coil surrounding the envelope.
  • This relay is also described, along with its characteristics and performance, etc., in an article Balanced polar mercury contact relay, by l. T. L. Brown and C. E. Pollard, in the November 1953 issue of The Bell System Technical Journal.
  • polar relays are magnetically polarized in order that a specified magnitude and polarity of current in the energizing winding will cause the armature to move from one contact to the other.
  • the two directions of motion are commonly referred to as the operate and the release directions, and this terminology will be used throughout subsequent discussion, description, specifica tion and, where necessary, claims.
  • the magnitude and/ or polarity of current to do either job may be anything .of the invention provide means for 2,806,186 Patented Sept. 10, 1957 desired, within the capabilities of the relay structure of course.
  • the current or currents specified for a particular relay are generally referred to as the operate and release sensitivities of the particular relay in question.
  • the main purpose of the present invention is to effect automatically, quickly and accurately any desired such sensitivity value or values for a particular relay.
  • Step 1 by manual manipulation of circuit means.
  • Steps 2, 3 and 4 are thereafter performed by the circuit automatically in response to a manual manipulation which amounts to a start signal.
  • a relay circuit applies a selected polarity of halfcycle alternating current as magnetizing pulses to electro magnets, which pulses thereby over-magnetize both of the bias magnets of the relay.
  • the relay circuit selects the other polarity of half-cycle alternating current to be applied to one electromagnet at a time thereby to demagnetize one or the other of the bias magnets at one time under the control of a relay control circuit and a selector.
  • This control circuit causes the test relay armature to operate .to one side, say the operate side, applies a test current to the relay, applies a relatively low demagnetizing pulse of specified magnitude of the selected half cycle as determined by the selector to the associated electromagnet, applies a reset current to the test relay to force the armature to operate to the said one side, applies a test current to said test relay and detects whether or not the armature of the test relay moves to the other side in response to said test current. If the armature does not so move, then the control circuit causes the selector to preselect a slightly larger magnitude of demagnetizing current and applies this slightly larger demagnetizing pulse to the associated electromagnet and then repeats the rest of the above procedure.
  • the control circuit will adjust itself to be able to go through the same procedure on the other side, say the release side, using the other 3 electromagnet, of course, and starting the magnitude of demagnetizing pulses at a specified low value of demagnetizing current as before.
  • control circuit will switch to the operate side and continue again because the adjustment of the release side will have caused an error in the previous operate side adjustment.
  • a feature of the present invention is the provision of a circuit for automatically adjusting the permanent magnet bias of a relay of the general type referred to herein.
  • a particular feature of the present invention is the provision of the necessary relay control circuits, current or voltage selector means, and predetermined test current value source or sources whereby the above adjust ment procedure is performed automatically.
  • Fig. 1 shows in block diagram form a functional layout of a typical adjusting set arranged for demagnetization
  • Fig. 2 illustrates how to arrange Figs. 6 and 7 to disclose a complete circuit according to one embodiment of the invention
  • Fig. 3 illustrates how to arrange Figs. 8 and 9 to disclose a complete circuit according to another embodiment of the invention
  • Fig. 4 shows a curve or graph or plot of test data applicable to the circuit of Figs. 6 and 7, which showing is referred to in the detailed description as an aid to understanding the functioning of the circuit of Figs. 6 and 7.
  • Fig. 5 shows data similar to that of Fig. 4 but associated with the circuit of Figs. 8 and 9;
  • Figs. 6 and 7 disclose the details of one complete embodiment
  • Figs. 8 and 9 disclose the details of another complete embodiment.
  • Fig. 1 shows a functional block diagram layout of an automatic relay adjusting set embodying the present in- -as 101 and 102.
  • a control circuit 103 is arranged to select under certain circumstances specified polarities of half-cycle pulses of the alternating-current power and to apply these over the operate or the release path through respective initial and final steps of power magnitude selector 104, 105, 106 and 1'07 to one or both of the electromagnets 101 and 102.
  • the control circuit 103 also, at certain times, exercises an operate-release control and a test reset control over the operation of the test circuit in cooperation with certain test relay current adjustment circuits which apply predetermined test and reset current values for the operate and release directions of motion of the armature 168 of relay 100.
  • the operation of the circuit is as follows. Assuming that the release direction of motion of the armature 103 is from contact 109 to contact 110 and that the operate direction is the reverse and assuming that the armature of relay 100 is initially in contact with the operate contact 110, the relay current adjustment circuits are first set such'that when an operate or release test 4 v or reset current is desired to be transmitted through the coil 111 of relay 104 these values will be those which are specified for the relay under adjustment.
  • the selector switches 105 and 1117 comprising a fine adjustment, will be set at their minimum voltage values.
  • the variacs 164 and 106 comprising the coarse adjustment, will be set at some predetermined relatively high value of voltage output.
  • the power control circuit 193 will apply to both of the electromagnets 1111 and 162 a few half cycles of specified polarity (say the positive half cycles) of the alternating-current power, whereby each of the relay contacts comprising permanent magnets 199 and 116 is overmagnetized. Thereafter, the coarse controls 1114 and 196 are manually readjusted to a selected minimum voltage position and the control circuit 103 will select the variac 166, the selector switch 163'] and the electromagnet 101, and will cause relatively low level reverse polarity halfcycle pulses of demagnetizing current to he applied to the electromagnet 161 for the purpose of partially demagnetizing the magnet contact 111 of relay 1%.
  • the release reset current value will be applied to the winding 111 of relay 1% to insure that the armature 1158 remains in contact with the operate contact magnet 11%.
  • the control circuit 103 will cause the release test current value to be applied to the winding 111 to determine whether or not the armature 1133 will transfer from contact 119 to contact 109.
  • the control circuit 193 causes the release power selector to adjust itself to a slightly increased amount of demagnetizing voltage and to apply this increased demagnetizing voltage again to the electromagnet 101 simultaneously with the previously-mentioned value of release reset current being applied to the winding-111.
  • the release test current is again applied to the winding 111.
  • the control circuit 1113 detects the travel of the armature 108 from the operate contact 119 to the release contact 109 in response to the preselected value of release test current. Thereupon the control circuit 103 switches its power control from the release to the operate side thereby enabling the variac and selector to apply demagnetizing pulses only to the electromagnet 1132.
  • the above procedure whereby successively increasing increments of half-cycle demagnetizing pulses are applied to electromagnet 1191, is repeated with respect to electromagnet 162 except that the reset and test relay current adjustment circuits which are used are the operate values instead of the release values.
  • the testing set proceeds to a conclusion whereby each of the magnets 109 and IE is successively and alternatively adjusted until the armature 108 buzzes back and forth from contact 109 to contact 110, and vice versa, immediately in response to the application to the winding 111 of the respective operate and release test current values Thi represents a condition, as detected by the control circuit 103, indicating that the relay 100 has been properly adjusted and that the test is completed.
  • Fig. 4 illustrates in a general manner what happens during the various adjustment sequences according to the embodiment of the invention wherein a shift is provided between coarse and fine power control which is in the embodiment of Figs. 6 and 7.
  • the release sensitivity and the operate sensitivity of the test relay are respectively 20 ampere turns and +43 ampere turns. This represents the condition of over-magnetization of both magnets prior to the demagnetizing procedure.
  • the first series of adjustments whereby the magnet 110 (the operate magnet contact) is demagnetized until the armature moves to the release contact 109 in response to the preselected value of release test current, places the relay under test in a condition where the respective release and operate sensitivities are +10 and +82 ampere turns. Thereupon, an adjustment sequence is effected upon the operate contact magnet 109, at'the conclusion of which the respective release and operate sensitivities are +3 and +56.
  • the circuit alternatively causes an adjustment sequence to the release and to the operate sides.
  • the release sensitivity of the relay is +30 and the operate sensitivity is +47, these being assumed as the final adjustment sensitivities of the relay.
  • Fig. is an illustration of what happens during the various adjustment sequences of a test circuit according to another embodiment of the invention, such as disclosed in Figs. 8 and 9, wherein there is no shift from a coarse .to a fine power adjustment, but wherein the entire pro- :cedure is controlled under a fine adjustment situation.
  • each of the lines on the curves marked with a black arrow represents one entire adjustment sequence on the particular release or operated side, as indicated, and that each one of these adjustment sequences may involve any number of separate consecutive demagnetizing pulses and reset and test current tests for that side.
  • Figs. 4 and 5 merely represent what the release and operate sensitivities of a test .relay would be if taken out of the test set and checked to ascertain what these sensitivities are at the end of each adjustment sequence.
  • test setembodying the present invention does not actually provide ampere turn sensitivity values for the relay at these specific times, but continues with the automatic adjustment sequences until such time as the relay under test buzzes to and from the operate and release contacts in rapid sequence under the control of the respective operate and release test currents, without the necessity of any further demagnetization.
  • the relay I in Fig. 7 is the relay under test and is shown as including an armature 718, an energizing winding 719, an operate contact 716 with an associated permanent magnet 717 and a release contact 714 with an associated permanent magnet 715. Located adjacent to the respective magnets 717 and 715 are the magnetizing-demagnetizing coils 713 and 712.
  • the armature 718 of the relay under test, relay I is shown in contact with the release contact 714.
  • the armature 718 of this type of relay will be in contact with one or the other of its contacts 714 and 716 and the showing of armature 718 in contact with the release contact 714 is merely illustrative of a suitable starting position.
  • the predetermined desired value of operate test current may be set up by potentiometer 702.
  • relay H By operating switch 720 to the reset position, relay H will be operated in a circuit extending from ground over switch 720 and through the winding of relay H to negative battery. This switches the circuit of the winding 719 of relay I to extend over contact 2 of relay H and contact 1 of relay D to potentiometer 705 which comprises part of a voltage divider including resistance 704 in series with potentiometer 705 across a battery.
  • the preselected value of operate reset current may be adjusted.
  • relay H operated and operates relays N and K of Fig. 6 and relays B, C and D of Fig. 7.
  • the operation of relays N, K and B are not significant at the moment.
  • Relays C and D are operated in a circuit extending from ground over switch 737, conductor 638 through the windings of relays C and D in parallel to negative battery, whereupon relays C and D operate.
  • switch 737 By maintaining switch 737 in its release position and moving switch 720 back to its test position, relay H will be released, whereupon the previously described circuit through the winding 719 of relay I is switched over contact 1 of relay H and contact 2 of relay C to the potentiometer 708, by means of the adjustment of which the release test value of current may be set up, at the conclusion of which switch 720 may be momentarily placed in its reset position to apply the release reset value of current to the winding 719 to insure that the armature 718 thereof ends up in contact with the release contact 714. Thereupon, switches 737 and 720 may be returned to their respective operate and test positions leaving the armature 718 in the position shown in Fig. 7.
  • switch 724 is closed to short circuit the meter 725 and switches 737 and 720 are placed in their respective run positions. In'this condition, all relays in the circuit of Figs. 6 and 7 are in the conditions as shown.
  • the alternatingcurrent source of power 633 is applied over the two bus bars marked 1 and I which extend to the similarly marked terminalsof the variacs 604 and 609,'to the primaries of transformers 612 and 613 and to potentiometers 610 and 611.
  • the manual adjustment knobs such as 605 for variac 604, may be moved to adjust the variacs and potentiometers 604, 609, 610 and 611 to their minimum voltage positions corresponding with phase 5
  • This manual adjustment is permitted by virtue of the fact that the magnetic clutch arrangements, such as comprising the electromagnet 603 and the friction clutch 602 associated with the variac 604, are not energized.
  • the wiper of the variac 609 carries zero voltage with respect to phase 6, and applies it to the I terminal of the potentiometer 611, whereupon the wiper. of potentiometer 611 carries zero voltage with respect to hand applies it over conductor 636 into Fig. 7 to the right side of the 'elect romagne t 713, the left side of the magnet of winding 713 extending back to contact 2 of relay B.
  • Fig. 7 to the right side of the 'elect romagne t 713, the left side of the magnet of winding 713 extending back to contact 2 of relay B.
  • the Wiper of variac 604 carries zero voltage with respect to 1, and applies it to the 6, terminal of the potentiometer 610, whereby the wiper of potentiometer 610 carries zero voltage with respect to 6 and applies it over conductor 635 into Fig. 7 to the left side of the winding of electromagnet 712, the right side of the winding thereof extending back to contact 1 of relay B.
  • the first operation in initiating the relay adjustment cycle is a preselected manual setting of the wiper of variac 604 by means of the knob 605 to a position which represents a substantial amount of alternating-current voltage on the wiper ofvariac 604 with respect to its a, terminal.
  • a similar setting is made of the variac 669. This, then, will apply this amount of aiternating-current power to conductors 635 and 636 extending into Fig. 7 through the electromagnets 712 and 713 back to the contacts 1 and 2 of relay B, one or the other of which will extend to the armature of relay A.
  • the magnetize-demagnetize switch 615 will now be "operated to its upper or magnetize position, causing a numberof things to happen as follows:
  • relay B places the electromagnets 712 and 713 in parallel between their respective power source conductors 635 and 636 and the contact 1 of relay B which, when relay A is operated, will extend back over conductor 637 into Fig. 6 and through resistance 634 back to the I phase of the alternatingcurrent power source.
  • phase 6, of the alternating-current power source 633 is extended over the left inner blade of switch 615 to the swinger armature of relay L, to the winding of relay K, to the primary windings of transformers 623 and 624, to the winding of relay N, and over conductor 638 into Fig. 7 to the windings of relays B, C and D.
  • phase 6, is connected to transformers 623 and 624 and to the swinger armature of relay L.
  • the phase 6, extends from the armature of relay L over the contact 1 thereof to the right-hand terminals of the operate and release drive motors 600 and 606.
  • the left-hand terminals of these drive motors extend to respective contacts 1 and 2 of relay K and over the armature of relay K, depending upon whether relay K is released or operated, back to the phase 1, bus.
  • the righthand terminals of the fine power control motors 607 and 60S extend over the contact of relay M back to contact 3 of relay L. It is thus apparent that with relay L in the position shown in Fig. 6, the coarse motors 600 and 606 are enabled for operation and the fine control motors 607 and 603 are disabled. The converse is true, as will be pointed out in subsequent description, when relay L is operated so that its armature makes contact with its contact 3.
  • Variac 620 selects a suitable quantity of alternatingcurrent voltage from the secondary of transformer 624, a portion thereof appearing across the resistance 622 in the voltage divider comprising resistance 621 and 622 and being applied to the series circuit including the winding of relay E and condenser 632. This causes a specified level of alternating current to flow in this circuit through the winding of relay E, the level of which is too low to cause the relay E to operate on the alternating current alone.
  • negative battery positive terminal grounded
  • condenser 632 shunts the lower side of the winding of relay E to ground. In this position of relay E, the condenser 632 will acquire a charge at a rate determined by the setting of the potentiometer 630
  • the circuit variables are chosen, preferably, so that the maximum value of direct current which may flow through the winding of relay E is by itself less than the operate value of current for relay E.
  • the time constant of the discharge circuit for condenser 632 is substantially constant.
  • the discharge current in this circuit including the winding of the relay E, has decreased to a sufiicient extent, the summation of the alternating and direct currents through the winding of relay E will be such as to permit relay E to again release, whereupon the armature of relay E again makes contact with its contact 2 to cause the abovedescribed cycle to repeat itself.
  • Potentiometer 630 changes the time constant in the charging circuit for condenser 632, thereby varying the amount of time from a specified starting point at whichrelay E will operate. Potentiometer 630, therefore, may be termed as a Percent Make Control; that is, it will control the amount of time when the armature of relay E is in contact with its contact 1 as compared to the total amount of time including the latter plus the amount of time when the armature of relay E is in contact with its contact 2.
  • Potentiometer 628 simultaneously adjusts the levels of the alternating and direct currents which are permitted to flow through the Winding of relay F and thereby adjusts the instant at which the composite current through the winding of relay F first reaches the operate value, at which time the armature of relay P will transfer from its contact 2 to its contact 1.
  • relay F When relay F transfers to its contact 1, a circuit is completed from ground over the armature and contact 1 of relay F to conductor 644 extending into Fig. 7, through the winding of relay A, and to negative battery through a parallel circuit of condenser 701 and potentiometer 700, and conductor 644 extends over the run positive of switch 720 to operate relay H for a purpose to be described later.
  • the condenser 701 in the circuit of relay A presents an instantaneous short circuit across the potentiometer 700 and permits relay A to operate very quickly upon the grounding of conductor 644. Sooner or later, depending upon the setting of potentiometer 700, condenser 701 will acquire a suflicient charge to cause relay A to release.
  • the settings of the potentiometer 628 in the circuit of relay F and potentiometer 700 in the circuit of relay A may be considered, respectively, as pulse start and pulse end potentiometers, whereby the specific instant with respect to the alternating-current Wave form at which relay A will operate is determined by potentiometer 628 and the specific instant of the release of relay A compared to the same alternating-current wave form is determined by the setting of potentiometer 700.
  • relay E will operate and release at a rate which is preferably a subharmonic of the alternating- -current frequency (but broadly may be any integral 634 and over conductor 637 to the contact of relay A.
  • the phase I 1 is extended from or both, to the wiper or wipers of the fine power control potentiometers 610 or 611 or both, to apply a pulse of alternating-current power to one or the other or both of these electromagnets during the time when relay A is operated.
  • An oscilloscope may be connected across the resistance 634 to observe the alternating-current half cycle of power which is transmitted through the contact of relay A.
  • the various adjustments such as the variac 620 and potentiometers 630, 628 and 700, may be adjusted such that the portion of alternating-current power delivered through the closed contact of relay A may be exactly a positive or negative half cycle more or less.
  • the switch 615 may be transferred from its upper to its lower or demagnetiz- .ing position.
  • the variacs 604 and 609 will be manually adjusted to a low value toward their 1 1 terminals. This causes a number of effects, as follows:
  • Phase Q1 will be applied over the left outer blade of switch 615 to the armature of relay L and thence over contact 2 thereof and conductor 642 to the top of potentiometer 727, whereby alternating current will be trans- .mitted through transformer 726 to be injected in series with the previously described direct-current reset and test values preselected by the potentiometers 702, 705, 708 and 709.
  • the right outer blade of switch 615 removes the short circuit across conductors 649 and 641, which removes the short circuit across contacts 1 and 2 of relay B in Fig. 7. This permits relay B to select by its release or operation which of the two electromagnets 712 and 713 will be permitted to receive demagnetizing pulses transmitted over the contact of relay A.
  • a circuit is completed from ground, over the right inner blade of switch 615, through resistance 617 and to battery through the windings of all of the magnetic clutch magnets, such as magnet 6133 associated with the operate coarse power control mechanism.
  • This causes all of the clutches, such as clutch 692, to engage, whereby the respective drive motors, if energized, will cause the associated wipers of the variacs 664 and 609 and potentiometers 610 and 611 to move from their in terminals toward their I z terminals at a fairly slow rate depending upon the speed of the associated motor and the amount of gear reduction in the respective reduction gear boxes, such as reduction gear box 6111 for motor 600.
  • a circuit is completed from ground, over the right middle blade of switch 615, through resistance 61% to negative battery through the Winding of relay L.
  • the condenser 646 across the winding of relay L will acquire a voltage charge, the value of which, however, is insufficient to cause the relay L to operate, but which is sufiicient to cause the relay L to stay operated once it is operated by other means.
  • relay H is also operated by an extension of conductor 6 34 over the run position of switch 720.
  • Relay H in operating, applies the operate reset value of current from potentiometer 705 over contact 1 of relay D and contact 2 of relay H, through winding 719 of the test relay I, through the secondary of transformer 726 and through switches 723 and 724 to the connection of resistances 721 and 722.
  • this value of operate reset current will insure that the armature 718 of relay I remains in contact with its contact 714 during the time when relay A is operated to apply a demagnetizing pulse to the electromagnet 712.
  • Relay A will release, terminating the application of a demagnetizing pulse to the electromagnet 712, at a time determined by the setting of potentiometer 706, as previously described. As soon as relay F releases to its contact 2, relay 1-1 will release. The release of relay H, therefore, occurs during the time when relay A is also released, which represents the time interval between applications of demagnetizing pulses to electromagnet 712. Relay H, in releasing, completes a circuit from the potentiometer 702 over contact 1 of relay C, contact 1 of relay H,
  • relay F operating for a short period of time, immobilizes the circuit of relay F, thereby permitting the armature of relay F to remain in contact with its contact 2, and thus preventing the immediate reoperation of relays A and H when relay E continues to oscillate.
  • Relay G in operating its armature to the right, also completes a circuit from ground over its contact 2, through the run position of switch 737, to conductor 638 which, in an obvious manner, causes the operation of relays B, C and D.
  • the grounding of conductor 63% in Fig. 6 causes the operation of relays N and K.
  • Relay N in operating, applies a ground pulse 'over its contact 1 through condenser 626 and through resistance 619 to the left side of the winding of relay L. Condenser 626 will very quickly, however, acquire a charge which then removes the additional. pulse from the winding of relay 'L, and relay L is arranged such that this single pulse will not cause it to operate.
  • Relay K in operating, transfers the phase P, of alternating-current power from its contact 1 to its contact 2 thereby stopping the operation of motor 6196 and starting the operation of motor 6%. Furthermore, during the time when the armature of relay G is in contact with its contacts 2 and 3, the previously charged condenser 732 associate with contact 1 of relay G will discharge through resistance 735.
  • relay H will again be operated, as previously described, and a circuit will becompleted from the release reset potentiometer 709 over contacts 2 of relays D and I-I-to apply to the winding 719 of relay I the predetermined value of release reset current whereby the armature'718 of relay I is forced to'remain in contact with the operate contact 716 of relay I.
  • Relay G will operate in the same manner as previously described, after a short delay caused by the short-circuiting effect of condenser 730, to move its armature from the right to the left, thereby releasing relays B, C, D, *N and K.
  • Relay L in so operating, causes the power circuit for motors 600 and 606 to be opened and causes the power circuit for motors 607 and 608 to be completed, in an obvious manner, over contact 3 of relay L and the contact of relay M (at such time as relay M releases upon the release of relay I into engagement with contact 2 of relay I as previously described).
  • the operation of relay L in addition to bringing into operation the fine power control in the upper right portion of Fig. 6 instead of the coarse control as previously effected, also removes from contact 2 of relay L the previously-described circuit whereby the trans former 726 in Fig. 7 receives alternating-current power. This causes the buzzing of the relay I to cease, whereupon relays M and I release and relays N and G cease to buzz.
  • relay I will even morerapidly and more quickly transfer back and forth between contacts 716 and 714, and vice versa, of relay I and'to in turn cause relay'G to switch quickly back and forth between its contacts .1 and 3, whereupon sufficiently frequent pulses will be applied to conductor-645 to cause relay J to remain operated in the position where contact 1 of relay J 'is .grounded continuously. This causes a continuous operation of relay M thereby to open at its contact the operating circuit for motors 607 and 608 to stop any further demagnetizing procedure.
  • the operator Before beginning a new-test, the operator will readjust the fine potentiometers 610 and 611 to their minimum or I positions and'may or may not return the variacs 604 'and.609 to their starting positions.
  • the ffine switch .627 maybe manually closed, if desired, assuming-that a'coarsc setting of the variacs 604 and 609 has been predetermined. This will cause the immediate operation of relay'L, as will be obvious, such that only the motors 607 and 608 controlling the fine, power control will be effective.
  • Figs. 8 and 9 performs substantially the same relay adjusting; job-as that described previously-in connection with Figs. 6 and 7.
  • the embodiment of Figs. 8 and 9 differs from the embodiment of Figs. 6 and 7 in a-number of deails the differences of major significance being as follows:
  • the means whereby successively increasing increments of demagnetizing current are supplied from the source of alternating-current power comprises a pair-- of step-by-step switches shown in the upper left portion; of Fig. 8. These switches are self-normalizing and, therefore, need not be manually readjusted tov their starting positions prior to each relay adjustment cycle.
  • relays 3, 4 and 5 With the release switch 903.and the reset switch 905' both unoperated, relays 3, 4 and 5 will be in the posi tion shown on Fig. 9. Whereupon, by manipulating.- switch 915 in one direction or the other depending upon:
  • potentiometer 906 has been set at the prescribed value of operate test current. Now, with switch 903 closed, operating relays 3 and 4 in an obvious cir :cuit to ground over the contact of switch 903, the potentiometer 912 will be effective over contact 2 of relay 3 and contact 1 of relay to setup the prescribed value of release test current. With switch 903 operated,
  • switch 905 is also operated, thereby operating relay 5 in an obvious circuit, the potentiometer 913 may be adjusted whereby it is effective over contact 2 of relay 4 and contact 2 of relay 5 to adjust the prescribed value of the release reset current.
  • potentiometer 909 is effective by means of contact 1 of relay 4 and contact 2 of relay 5 to establish the prescribed value of operate reset current. Switches 903 and 905 may then be released and switch 916 may now be closed to short-circuit the meter 917.
  • alternating-current power is applied from the source 800 thereof, through fuse 801 and switch 802, to the two alternating-current power lines designated phase 1 and phase I
  • the magnetizing switch 900 will be closed causing the following operations:
  • Fig. 8 will be operated in a circuit extending from ground over contact 4 of switch 900 and over conductor 845 to the windings of relays 15 and 16.
  • a circuit is completed from ground over contact 5 of switch 900, conductor 838 into Fig. 8 and over the contact of relay 11 to place ground on the bottom terminal of the secondary winding of transformer. 803.
  • Grounds are extended over contacts 1 and 3 of switch 900 and over respective conductors 848 and 856 extending intoFig. 8 to the respective wipers 820 and 824 of the two step-by-step selectors.
  • a circuit is completed for operating relay 14 in Fig. 8 extending from the phase P2 power line through the winding of relay 14, conductor 851, contact 2 of switch 900, conductor 852, back to the phase In power line.
  • Relay 9 in Fig. 8 operates in the same fashion as previously described for relay E inFig. 6; that is, relay 9 will oscillate its armature back and forth between its contacts 1 and 2 at a rate which is preferably a subharmonic of the alternating-current frequency (such as three to five cycles per second as compared to a 60-cycle source).
  • the rate at which relay 9 oscillates is determined primarily by the settings of the variac 825 and the potentiometer 826, both comprising, in effect, a frequency adjustment.
  • relay 10 Each time relay 9 operates its armature against its contact 2, relay 10 will be operated by a combination of alternating and direct currents, and it will operate at an instant with respect to the alternating-current wave form 1% determined by the adjustment of the pulse start potentiometer 830.
  • Relay 1 will thereupon operate and will stay operated for a short interval of time depending upon the setting of the pulse stop potentiometer 858, which adjusts the time constant of the circuit whereby condenser 859 will acquire a charge suflicient to cause relay 1 to release.
  • the various adjustments comprising variac 825, frequency potentiometer 826, percent make potentiometer 829, pulse start potentiometer 830 and pulse stop potentiometer 858 are preferably made with an oscilloscope connected across the terminals of resistance 846, such that the relay 1 will close its contact when the alternatingcurrent wave form goes through zero in one direction and will open its contact when the alternating-current wave form goes through zero in the other direction; that is, the contact of relay 1 will be closed only during a selected polarity half cycle (more or less) of the alternatingcurrent power, all as previously described with respect to relay A of Fig. 7.
  • relay 1 During the operation of relay 1, a circuit is completed from the phase @1 power line over the contact of relay 15, in parallel over contacts 1 and 2 of relay 16, over conductors 857 and 844 into Fig. 9, to the respective right and left sides of the windings of the electromagnets 919 and 917, back over respective conductors 850 and 849, to the respective contacts 2 and 1 of relay 2. It will be noted that the contacts 1 and 2 of relay 2 are short circuited by means of contact 1 of the operated relay 14.
  • Each of these stepping switches continues to step automatically until position 22 is arrived at, whereupon ground will extend over the wipers 819 and 823 to battery through the right-hand windings of the respective relays 7 and 8.
  • These relays 7 and 8 will thereupon operate their armatures into the positions shown in contact with their respective contacts 1. If the respective stepping switches are initially in the position shown, the respective relays 7 and 8 will therefore nevertheless be in the position shown. It will be noticed that with relays 7 and 8 in the positions shown the primary windings of transformers 812 and 808 are short-eircuited so that no alternatingcurrent voltage or current is induced into the secondaries of these transformers.
  • the magnetizing switch 900 will now be released preparatory to setting the circuit into automatic operation for demagnetizing the two permanent magnets 925 and 924 of the relay under test, thereby releasing relays 15 and 16, removing ground from the wipers 820 and 824 of the stepping switches, releasing relay 14 and removing 17 ground from conductor 838 thereby stopping the oscillation of relay 9, etc.
  • switches 902 and 904 are placed in their run positions and the demagnetizing switch 901 is closed.
  • the closure of the demagnetizing switch 901 accomplishes the following things:
  • relay 5 will release, thereby causing the operate test value of current to be applied from potentiometer 906 to the winding 921 of the relay under test.
  • relay 13 had been operated and released once thereby causing the stepping magnet SEL2 to operate and release once, advancing the associated wiper arms one step.
  • This movement of the armature of relay 12 causes the charge previously acquired by condenser 833 to be dissipated in resistance 835 and causes a ground pulse to be applied over the armature of relay 12, contact 3 thereof through condenser 834, to the winding of relay 11, which ground, augmenting the charge normally carried by condenser 860, will cause relay 11 to operate momentarily until condenser 834 can acquire a sufiicient charge to cause relay 11 to release.
  • This momentary operation and release of relay 11 opens the circuit between the grounded conductor 838 and the bottom terminal of the secondary winding of the transformer 803, thereby causing the relay 9 to stop oscillating.
  • Ground is also applied over contact 1 of relay 12 to conductor 839 extending into Fig. 9 and over the contact of switch 902 to operate relays 3 and 4 and extending over conductor 855 into Fig. 8 to operate relays 6 and 2.
  • relay 9 Upon the release of relay 11, after a momentary delay above mentioned, relay 9 is again permitted to oscillate to again cause relays 10, 1 and 5 to operate to cause a 19 r demagnetizing-pulse to be applied to the electromagnet 919.
  • 'lThe" circuit for this demagnetizing pulse extends from the phase I side of the power line, over the contact of relay 18, through fuse S47, resistance 846, contact of relay 1, resistance 832, contact 2 of relay 2, conductor 850, through the winding of the electromagnet 919 back over conductor 857, contact 1 of relay 17, to wiper 818 of the upper stepping switch and out over the wiper 813, through the secondary of transformer 812, back to the wiper of variac 811.
  • the only voltage available in this demagnetizing pulse circuit is the voltage derived from the wiper arm of variac 811 and the small amount of voltage available due to the position of the wiper arm 813, by virtue of the fact that relay 7 is short-circuiting the primary of transformer 812.
  • potentiometer 913 will cause the release reset value of current to be applied to the winding 921 of the relay under test to force the armature 920 to remain in contact with the operate contact 923 of the relay under 'test.
  • the potentiometer 912 will apply to the winding 921 of the relay under test the prescribed value of release test current.
  • the rapid flashing back and forth of the two lamps 928 and 929 provides a visual indication to the operator that the relay under test has arrived at a con dition whereby the permanent magnets 925 and 924 have been demagnetized to such an extent that the respective operate and release test values of current prescribed for the relay under test properly cause the armature 920 to perform as prescribed.
  • the relay under test may now be removed from the circuit and another relay may be placed under test, whereupon the above procedure is repeated, it being appreciated that as soon as the magnetizing switch 900 is operated with the demagentizing switch 931 released, the two stepping mechanism of'Fig. 8 will automatically adjust themselves to their normal starting positions.
  • A'circuit for automatically adjusting the permanent magnet bias of a test relay including an energizing winding and a contact and a permanent magnet and a magnetic armature movable in operable relation to said contact 7 under the influence of the combination of the magnetic field produced by' the energization of said winding and the magnetic field of said magnet, said circuit comprising a source of electric power, switch means having a magnetizing and a demagnetizing position, a magnetizingdemagnetizing coil adaptable to magnetize or demagnetize said test relay magnet, a power control circuit responsive to the op'eration of said switch means into its magnetizing position to apply at least one pulse of current of a magnetizing polarity to said coil from said source, said current pulse being adaptable to over-magnetize said magnet, variable means operable to deliver variable increments of power from said source to said coil under the control of said control circuit, means automatically responsive to the operation of said switch means into its demagnetizing position to cause said control circuit to control said variable means to apply a sequence of
  • a circuit for automatically adjusting the permanent magnet bias of a test relay including an energizing winding and a contact and a permanent magnet and a magnetic armature and movable in operable relation to said contactunder the influence of the combination of the magnetic field produced by the energization of said winding and the magnetic field of said magnet, said circuit comprising a source of electric power, switch means having a magnetizing and a demagnetizing position, a magnetizing-demagnetizing coil adaptable to magnetize or demagnetize said test relay magnet, a power control circuit responsive to the operation of said switch means into its magnetizing position to apply at least one pulse of current of magnetizing polarity to said coil from said source, said-current pulse being adaptable to over-magnetize said magnet, variable means operable to deliver variable increments of power from said source to said coil under the control of said control circuit, means automatically responsive to the operation of said switch means into its demagnetizing position to cause said control circuit to control said variable means to apply a sequence of pulses of current of a dem
  • a circuit for automatically adjusting the permanent magnet bias of a test relay including an energizing winding and a contact and a permanent magnet and a magnetic armature movable in operable relation to said contact under the influence of the combination of the magnetic field produced by the energization of said winding and the magnetic field of said magnet, said circuit comprising a source of electric power, a manually operable switch having a magnetizing and a demagnetizing position, a magnetizing-demagnetizing coil adaptable to magnetize or demagnetize said test relay magnet, a power control relay circuit responsive to the operation of said switch into its magnetizing position to apply at least one pulse of current of a magnetizing polarity to said coil from said source, said current pulse being adaptable to over-magnetize said magnet, a power selector operable to deliver variable increments of power from said source to said coil under the control of said relay control circuit, relay means in said relay control circuit automatically respon sive to the operation of said switch into its demagnetizing position to cause said power selector to apply
  • a circuit for automatically adjusting the permanent magnet bias of a test relay including an energizing winding and a contact and a permanent magnet and a magnetic armature and movable in operable relation to said contact under the influence of the combination of the magnetic field produced by the energization of said winding and the magnetic field of said magnet, said circuit comprising a source of electric power, a manually operable switch having a magnetizing and a demagnetizing position, a magnetizing-demagnetizing coil adaptable to magnetize or demagnetize said test relay magnet, a power control relay circuit including a pulsing relay and responsive to the operation of said switch into its magnetizing position to apply at least one pulse of current of a magnetizing polarity to said coil from said source under the control of said pulsing relay, said current pulse being adaptable to over-magnetize said magnet, a power selector operative to deliver variable increments of power from said source to said coil under the control of said relay control circuit, means in said relay control circuit including said pulsing relay
  • a circuit for automatically adjusting the permanent magnet bias of a test relay including an energizing winding and a contact and a permanent magnet and a magnetic armature movable in operable relation to said contact under the influence of the combination of the magnetic field produced by the energization of said Winding and the magnetic field of said magnet, said circuit comprising a source of electric power, a manually operable switch having a magnetizing and a demagnetizing position, a magnetizing-demagnetizing coil adaptable to magnetize or demagnetize said test relay magnet, a power control relay circuit including a pulsing relay and responsive to the operation of said switch into its magnetizing position to apply at least one pulse of current of a magnetizing polarity to said coil from said source under the control of said pulsing relay, said current pulse being adaptable to overmagnetize said magnet, 21 power selector operable to deliver variable increments of power from said source to said coil under the control of said relay control circuit, relay means in said relay control circuit including said pulsing relay and
  • a circuit for automatically adjusting the permanent magnet bias of a test relay including an energizing winding and two separate contacts and a permanent magnet associated with each contact and a magnetic armature attracted magnetically in opposite directions towards each contact by respective magnets and movable away from each respective contact under the influence of the combination of the magnetic field produced by the energization of said winding and the magnetic fields of said magnets, said circuit comprising a source of power, switch means having a magnetizing and a demagnetizing position, a magnetizing-demagnetizing coil adaptable to magne tize or demagnetize each of said test relay magnets, a power control circuit responsive to the operation of said switch means into its magnetizing position to apply at least one pulse of current of a magnetizing polarity to said coils from said source, said current pulse being adaptable to over-magnetize said magnets, variable means operable to deliver variable increments of power from said source to said coils under the control of said control circuit, means operative at respective odd and even times by said control circuit and
  • a circuit for automatically adjusting the permanent magnet bias of a test relay including an energizing winding and two separate contacts and a permanent magnet associated with each contact and a magnetic armature attracted magnetically in opposite directions towards each contact by respective magnets and movable away from each respective contact under the influence of the combination of the magnetic field produced by the energization of said winding and the magnetic fields of said magnets, said circuit comprising a source of power, switch means having a magnetizing and a demagnetizing position, a magnetizing-demagnetizing coil adaptable to magnetize or demagnetize each of said test relay magnets, a power control circuit responsive to the operation of said switch means into its magnetizing position to apply at least one pulse of current of a magnetizing polarity to said coils from said source, said current pulse being adaptable to over-magnetize said magnets, variable means operable to deliver variable increments of power from said source to said coils under the control of said control circuit, means operative at respective odd and even times by said control circuit and adaptable to detect
  • a circuit for automatically adjusting the permanent magnet bias of a test relay including an energizing winding and two separate contacts and a permanent magnet associated with each contact and a magnetic armature attracted magnetically in opposite directions towards each contact by respective magnets and movable away from each respective contact under the influence of the combination of the magnetic field produced by the energization of said winding and the magnetic fields of said magnets, said circuit comprising a source of power, switch means having a magnetizing and a demagnetizing position, a magnetizing-demagnetizing coil adaptable to magnetize or demagnetize each of said test relay magnets, a power control circuit responsive to the operation of said switch means into its magnetizing position to apply at least one pulse of current of a magnetizing polarity to said coils from said source, said current pulse being adaptable to over-magnetize said magnets, variable means for each coil and operable to deliver variable increments of power from said source to the associated coil under the control of said control circuit, means automatically responsive to the operation of said switch means into its demagne
  • a circuit for automatically adjusting the permanent magnet bias of a test relay including an energizing winding and two separate contacts comprising permanent magnets and a magnetic armature attracted magnetically in opposite directions towards each contact by respective magnets and movable away from each respective contact under the influence of the combination of the magnetic field produced by the energization of said winding and the magnetic fields of said magnets, said circuit comprising a source of power, a manually operable switch having a magnetizing and a demagnetizing position, a magnetizing-demagnetizing coil adaptable to magnetize or demagnetize each of said test relay magnets, a power control relay circuit responsive to the operation of said switch into its magnetizing position to apply at least one pulse of current of a magnetizing polarity to said coils from said source, said current pulse being adaptable to over-magnetize said magnets, a power selector for each coil and operative to deliver variable increments of power from said source to the associated coil under the control of said relay control circuit, relay means in said relay control circuit automatically responsive to
  • Acircuit for automatically adjusting the perman'ent magnet bias of a test relay including an energizing winding and two separate contacts comprising permanent magnets and a magnetic armature attracted magnetically in opposite directions towards each contact by respective magnets and movable away from each respective contact under the influence of the combination of the magnetic field produced by the energization of said winding and the magnetic fields of said magnets, said 27 circuit comprising a source of power, a manually operable switch having a magnetizing and a demagnetizing position, a magnetizing-demagnetizing coil adaptable to magnetize or demagnetize each of said test relay magnets, a power control relay circuit including a relay controlled by said source to oscillate at a desired rate and including a power relay controlled by said oscillating relay, said relay control circuit responsive to the operation of said switch into its demagnetizing position to apply at least one pulse of current of a magnetizing polarity from said source to said coils under the control of said power relay said current pulse being adaptable to over-magnetize said
  • means including said relay control circuit and said steering relay and said group of relays efiective in response to succeeding respective even and odd operations of said detecting means at the end of succeeding respective even and odd sequences to control said first and second power selectors alternately to'apply succeeding respective odd and even additional sequences of demagnetizing pulses of still increasing magnitude from said source to respective coils through the agency of said power relay, said addition sequences of pulses being adaptable to successively further demagnetize said magnets, and relay means including said detecting relay means and responsive to immediate odd and even operations of said detecting means pursuant to respective immediately preceding even and odd operations of said detecting means to dis-able said oscillating relay thereby to prevent any further demagnetizing sequences and adaptable to indicate completion of the adjustment of the permanent magnet bias of both magnets.
  • a circuit for automatically adjusting the permanent magnet bias of a test relay including an energizing winding and a contact and a permanent magnet and a magnetic armature movable in operable relation to said contact under the influence of the combination of the magnetic field produced by energization of said winding and the magnetic field of said magnet, said circuit comprising a source of electric power, switch means having a demagnetizing position, a coil adaptable to magnetically influence said test relay magnet, a power control circuit, selector means operable to deliver increments of power from said source to said coil under the control of said control switch, means responsive to the operation of said switch means into its demagnetizing position to cause said control circuit to control said selector means to apply at least one pulse of current of a demagnetizing polarity to said coil from said source, means operative by said control circuit during the application of said demagnetizing pulse to said coil and adaptable to cause said armature to be placed into contact with said contact and operative by said control circuit after said demagnetizing pulse is applied to said coil
  • a circuit for automatically adjusting the permanent magnet bias of a test relay including an energizing winding and a contact and a permanent magnet and a magnetic armature movable in operable relation to said contact under the influence of the combination of the magnetic field produced by the energization of said winding and the magnetic field of said magnet, said circuit comprising a source of electric power, switch means having a demagnetizing position, a coil adaptable to magnetically influence said test relay magnet, a power control circuit responsive to the operation of said switch means into its magnetizing position to apply at least one pulse of current of a magnetizing polarity to said coil from said source, said current pulse being adaptable to over-magnetize said magnet, variable means operable to deliver variable increments of power from said source to said coil under the control of said control circuit, means automatically responsive to the operation of said switch means into its demagnetizing position to cause said control circuit to control said variable means to apply a sequence of pulses of current of a demagnetizing polarity to said coil from said source, said

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DEW16193A DE952289C (de) 1954-03-24 1955-03-11 Geraet zur selbsttaetigen Einstellung der permanenten Vormagnetisierung von Relais

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2930944A (en) * 1956-03-21 1960-03-29 Radio Frequency Lab Inc Method and apparatus for pulling down magnets
US2940036A (en) * 1956-06-26 1960-06-07 Western Electric Co Apparatus for dynamically gaging relays
US3211864A (en) * 1962-03-26 1965-10-12 Honeywell Inc Thermostatic switch having a permanent magnet for snap action closing
US3237095A (en) * 1963-12-27 1966-02-22 William R Patterson Test device for impact and centrifugal switches utilizing a magnetic field to simulate inertial forces
US3243696A (en) * 1961-07-31 1966-03-29 Western Electric Co Apparatus for adjusting relays to operate and release at desired values of current
US3259839A (en) * 1960-01-27 1966-07-05 Crabtree & Co Ltd J A Electric circuit breakers
US3479584A (en) * 1966-09-20 1969-11-18 Western Electric Co System for adjusting operating and release sensitivities of magnetically biased relay armatures
US3924178A (en) * 1974-07-03 1975-12-02 Deutsch Relays Inc Relay tester
US4104591A (en) * 1975-08-01 1978-08-01 Elmeg Elektro-Mechanik Gmbh Method of adjusting a permanent magnet by using a hypothetical demagnetization curve lower than the actual value
US4307345A (en) * 1979-11-26 1981-12-22 E.I.L. Instruments, Inc. Circuit recloser test set

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3887412D1 (de) * 1987-09-15 1994-03-10 Siemens Ag Verfahren und Einrichtung zum Justieren von Haltemagnetauslösern.

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2577602A (en) * 1947-10-01 1951-12-04 Bell Telephone Labor Inc Method for adjusting the sensitivity of contact devices
US2590228A (en) * 1948-12-31 1952-03-25 Bell Telephone Labor Inc Method of adjusting polar relays
US2632035A (en) * 1950-05-06 1953-03-17 Niles Bement Pond Co Demagnetizing control system

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2577602A (en) * 1947-10-01 1951-12-04 Bell Telephone Labor Inc Method for adjusting the sensitivity of contact devices
US2590228A (en) * 1948-12-31 1952-03-25 Bell Telephone Labor Inc Method of adjusting polar relays
US2632035A (en) * 1950-05-06 1953-03-17 Niles Bement Pond Co Demagnetizing control system

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2930944A (en) * 1956-03-21 1960-03-29 Radio Frequency Lab Inc Method and apparatus for pulling down magnets
US2940036A (en) * 1956-06-26 1960-06-07 Western Electric Co Apparatus for dynamically gaging relays
US3259839A (en) * 1960-01-27 1966-07-05 Crabtree & Co Ltd J A Electric circuit breakers
US3243696A (en) * 1961-07-31 1966-03-29 Western Electric Co Apparatus for adjusting relays to operate and release at desired values of current
US3211864A (en) * 1962-03-26 1965-10-12 Honeywell Inc Thermostatic switch having a permanent magnet for snap action closing
US3237095A (en) * 1963-12-27 1966-02-22 William R Patterson Test device for impact and centrifugal switches utilizing a magnetic field to simulate inertial forces
US3479584A (en) * 1966-09-20 1969-11-18 Western Electric Co System for adjusting operating and release sensitivities of magnetically biased relay armatures
US3924178A (en) * 1974-07-03 1975-12-02 Deutsch Relays Inc Relay tester
US4104591A (en) * 1975-08-01 1978-08-01 Elmeg Elektro-Mechanik Gmbh Method of adjusting a permanent magnet by using a hypothetical demagnetization curve lower than the actual value
US4307345A (en) * 1979-11-26 1981-12-22 E.I.L. Instruments, Inc. Circuit recloser test set

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