Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H71/00—Details of the protective switches or relays covered by groups H01H73/00 - H01H83/00
  • H01H71/74—Means for adjusting the conditions under which the device will function to provide protection
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H71/00—Details of the protective switches or relays covered by groups H01H73/00 - H01H83/00
  • H01H71/10—Operating or release mechanisms
  • H01H71/12—Automatic release mechanisms with or without manual release
  • H01H71/14—Electrothermal mechanisms
  • H01H71/16—Electrothermal mechanisms with bimetal element
  • H01H71/164—Heating elements
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H71/00—Details of the protective switches or relays covered by groups H01H73/00 - H01H83/00
  • H01H71/74—Means for adjusting the conditions under which the device will function to provide protection
  • H01H2071/749—Means for adjusting the conditions under which the device will function to provide protection with a shunt element connected in parallel to magnetic or thermal trip elements, e.g. for adjusting trip current
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H71/00—Details of the protective switches or relays covered by groups H01H73/00 - H01H83/00
  • H01H71/74—Means for adjusting the conditions under which the device will function to provide protection
  • H01H71/7418—Adjusting both electrothermal and electromagnetic mechanism

Definitions

• the invention relates to a method for expanding the adjustment range of a thermomechanitive overload protection device, in which a Stromeinstellwert can be specified by the user and in which a defined tripping characteristic (current-time-tripping curve) of the protective device to be achieved.
• the invention also relates to an associated thermo-mechanical overload protection devices and their use.
• Non-electronic overload relays or overload tripping contain thermal tripping devices, such as bimetals, snap disks or the like, and actuate - according to a current-time tripping characteristic - a mechanism which ensures at excessive operating currents for elimination of the affected branch current.
• This mechanism is in particular a lock release, a control switch contact or a signal detector.
• the mechanism includes other elements for setting the overload trip to an operating current value within the current setting range. To eliminate the influence of ambient temperature on overload trip, the mechanism generally includes additional temperature compensation elements.
• an adjustment device for a switching device which contains a U-shaped bimetal with shunt connected in parallel.
• the shunt connects the two legs of the bimetal at different, but fixed by welding connection position.
• the bimetal is current-carrying only on the predetermined partial length. which is used to determine the tripping current range.
• the dimensioning, ie the positioning of the tripping current range of the overload release is effected by the cross-sectional size of the heating resistor, which is electrically connected in parallel with the bimetal and heats the same.
• its working range can be placed within a current range of 10 to 200A. So it can be realized in terms of manufacturing technology easily fixed adjustment ranges between 10 and 200 A.
• thermomagnetic tripping device of bimetal and the first (bimetallic) shunt, which excite a hinged armature magnetic release and a second shunt, which is connected in parallel to the bimetal and the first shunt, known.
• the second shunt is used to set the tripping value.
• German Patent Specification No. 473 338 already discloses a magnetic-thermal overcurrent switch, in which contact means are provided with which discrete values of the sensitivity can be predetermined.
• the Weiteinstell Scheme of overload protection devices is consistently implemented by electronic overload relay or electronic overload release.
• the overload current is detected by current transformers and a trigger signal is generated with an electronically mapped current-time tripping characteristic.
• An advantage of this electronic solution is that the 'heating', i. the electrical power loss of the overload protection device does not depend on its current setting value, apart from non-functional power loss due to electrical line resistance in the protective device.
• Another object of the invention is always to provide a definite nated current-time tripping characteristic for the trigger to realize.
• the tuning of the response value of the short-circuit quick release should also be improved depending on the setting value of the overload release described above.
• claims 12 and 13 indicate alternative process guides for overload protection.
• An associated overload protection device is the subject of claim 17. Further developments of the method, the associated overload protection devices and their uses are specified in further claims.
• the contact means can be designed either mountable or switchable.
• the wide adjustment range can be divided into a first adjustment range with lower and upper limit values and into a different second adjustment range with different lower and upper limit values.
• thermal tripping devices are used to realize the Weiteinstell Symposium Serieses of non-electronic overload protection devices to which current-carrying components can be switched according to the invention.
• the switching action can be carried out in detail by mechanically operated switch contacts or by mechanically mountable contact elements.
• the conceptual difference lies in the readiness for switching by means of an operable switch contact, during operation of the overload protection device and the monitored by her switching device, against a forced-controlled decommissioning of the overload protection device and the monitored switching device in the Ummontage the mountable contact element for selecting the adjustment range.
• a parallel current path containing at least one switching device installed.
• a parallel current path containing at least one switching device installed.
• the opening / closing of the parallel branch results in two adjustment ranges between the lower setting current I ul of the lower region and the upper adjustment current I 02 of the upper region.
• I ui to I o i In the opened state of the switch remains unchanged the (lower) range of I ui to I o i, where I o i ⁇ 1.4 I u i to 1.6 I u i- If the switch is closed applies for the upper range preferably I u2 «I.
• the impedance of the parallel branch is tuned such that it carries the relative current component (I u2 -I u i) / I u i of the operating current I r when the upper setting range is switched on.
• the bimetal is heated only by the relative current component I i u / Iui.
• the latter principle in particular for multi-phase devices, be extended by a) the current or setting areas at any time and repeatedly, so even during operation can be set or adjusted b) several parallel branches in stages can be switched to a change-over switch, which increases the setting range by one power (level 1: square of the lower setting range, level 2: 3rd power of the lower setting range, etc.), c) the temperature compensation for all phases uniformly on one d) a central mechanism exists which actuates the contact means of the parallel paths in all phases simultaneously, e) the basic release mechanism (bimetal, heating conductor, mechanical coupling bimetal to tripping gan / switching lock), including the protection against phase imbalance or phase failure remains unchanged, f) that the parallel path, including the contact means and the current path resistances, modular to the device are plugged without significantly changing the basic unit.
• the power loss generated in the parallel branch is ideally coupled to 100% on the bimetal.
• the impedance of the parallel branch is dimensioned such that when the parallel branch is activated, the sum of the power losses due to the bimetallic branch and the parallel branch in the upper setting range is equal to the power loss of the bimetallic branch with the parallel branch open in the lower setting range.
• the shunt is thermally connected to the bimetal either as a heating coil or indirect heating.
• the division of the Stromeinstell Anlagenes specified as Weiteinstell Switzerland is not realized by a switchable parallel current branch, but by an electrically switchable in series, additional heating conductor.
• the additional heating conductor is thermally coupled to the overload release in such a way that its heating power is essentially completely transferred to the thermomechanical actuator.
• the additional heating conductor is connected in series, the lower range of the wide setting range is switched on.
• Another measure within the scope of the invention is the realization of a defined current-time tripping characteristic. This is thermally enhanced by the thermal conductivity, especially at low overload currents, and by the heat capacity, especially at high overload currents, of both the active elements, i. the current paths, the bimetal and u. U. the heating element or the contact element, as well as the passive components, such as fasteners, housing, surrounding air, influenced.
• this problem is solved as a function of the abovementioned types of construction as follows:
• the placement of the components of the parallel branch, ie contact means and shunt thermally insulated in separate rooms of the or in special attachable modules In the case of the power matching principle, ie with approximately complete coupling of the power loss of the parallel branch into the bimetal, a thermally intimate connection of the shunt in the parallel branch with the bimetal takes place. Since a short-circuit current load of the shunt is always lower than that of the bimetallic branch with the parallel branch switched off, u. U.
• the shunt can be designed correspondingly small in its geometric dimensions, which significantly reduces the heat capacity. It is advantageous to use materials that have a high electrical resistivity. CuNi or CrAl alloys are preferably used for this purpose.
• Another feature of this arrangement is the lowest possible resistance of the / the contact means (s).
• Particularly suitable are large-area contacts with large contact forces, such.
• B. plug contacts banana plugs, Lyra- or blade contacts
• contacts with special low-resistance contact materials for example silver (Ag) alloys, such as AgNi or fine grain silver, or silver (Ag) composite materials, such as Ag metal oxides.
• the invention improves the tuning of the response value of the short-circuit rapid release as a function of the setting value of the overload release described above.
• Circuit-breakers are known to simultaneously adjust the short-circuit quick release by setting the overload relay. This ensures that the short-circuit quick release becomes active at a certain, but fixed, multiple of the adjustable operating current (operating current).
• the response time of the short-circuit fast release is so wide that the equipment is no longer adequately protected in the event of short-circuit and lower setting current I u .
• this problem can be solved, for example, by partial tapping of the short-circuit quick release.
• the switchable parallel branch described above is electrically connected to the coil of the short-circuit quick release in such a way that the Amperewindung number per setting range, ie with or without switched
• the adaptation of the magnetic release can be carried out in the invention in four different ways:
• a parallel circuit of a discharge current branch can lead to the solenoid. At a current factor of 1.5, the relative current component 0.5 is guided via the discharge current branch, while the magnetic coil carries the relative current component 1.
• Ampere turn number when the tap is turned off relative to the current 1 is equal to the ampere-turn number when the tap is switched to the relative current of 1.5.
• a partial current can be drawn off by tapping the winding, so that the relative current 1.5 corresponds to the total magnetic excitation of the winding, again corresponding to the relative current component 1.
• the proportionality factor can also be adjusted by the air gap width between the moveable magnet armature and the magnetic opposite pole instead of the ampere-turn number. This is also increased by a factor of 1.5 to increase the operating current from 1 to 1.5 in relative units.
• the setting of the magnetic release from the lower current setting range to the upper current setting range of the so-called wide setting range is done with the same contact means as for the overload release. Additionally or alternatively, mechanical elements for adjusting the air gap width or the spring travel can be coupled to the contact means.
• FIG. 1 shows a construction for an overload release with parallel branch and thermal decoupling
• FIG. 2 shows a bimetallic release with parallel-current branch
• FIG. 3 shows an embodiment according to FIG. 1 for switching on / off several adjustment ranges of the wide-adjustment range
• FIG. 4 shows a design for an overload release with a plurality of parallel branches and thermal coupling of the individual branches and the partial tap of a short-circuiting-blade release
• FIG. 5 shows a bimetal branch with parallel heating windings
• FIG. 6 shows a parallel connection of two heating windings according to FIG. 5 with a tripping coil of n turns
• FIG. 7 shows examples of a thermal coupling of the bimetal to the shunt of the parallel branch
• FIG. 8 shows further examples of a thermal coupling according to FIG. 7, but with an additional heating conductor for the bimetallic current path
• Figure 9 is a current-time characteristic for a purely thermal trip (overload trip)
• Figure 10 is a current-time characteristic for a combined thermal / magnetic trip (overload / short-circuit trip)
• Figure 11 shows a three-pole switch using the means for implementation the Weiteinstell Schemees, wherein a thermal coupling of the parallel branch is avoided to the overload release,
• FIG. 13 shows a three-pole switch with means for realizing the Weiteinstell Schemees of Figure 11 o- of Figure 12 and with engageable tap the
• Shutter solenoid The realization of the wide adjustment range according to the invention is shown in different variants using the example of an overload relay with bimetal and heating coil. The different training of the individual examples is each separately, whose function is then described together:
• reference numeral 1 denotes a first branch and 2 a second branch, which is guided parallel to the first branch.
• reference numeral 10 denotes a bimetal having a temperature-dependent switching function, as is known from the prior art.
• Figure 1 illustrates the principle of resistance matching: the highlighted fields characterize the thermal separation between bimetallic branch and parallel branch: In detail, located in the region of the current branch 1, a bimetal 11 with a heat conductor 12 and in the region of the current branch 2, a shunt 21.
• the parallel branch 2 is switchable via a switch 25.
• a unit with control contacts 15 is present, which includes a closer and a normally closed. These are indirectly actuated mechanically by a bimetal trigger 10. Alternatively, the bimetallic actuator 10 can also actuate a switch lock. Furthermore, according to Figure 1 in the parallel-current branch 2, a switching contact 25 with a downstream resistor 21, which corresponds to the shunt of Figure 1, arranged.
• the default setting of an overload relay lies 11 to 16 A.
• the electrical resistance RBime- ta u of bimetal with heating conductors is about 8.6 milliohms for this purpose.
• the parallel resistor receives - including the line and contact resistance - the resistance value:
• the electrical connection of the parallel resistor is made at the electrical feeds of the terminals to the bimetal and the heating conductor, wherein the connection lines are guided via a mechanically actuated switching contact.
• This can for example be designed as Bananensteck token whose plug is inserted within a pipe guide against an opening spring in the banana socket, and its on and off position can be fixed by suitable notches.
• the parallel resistor is preferably made of resistance material with a low temperature coefficient and sufficiently high application temperature.
• the parallel-current branches with associated switch contacts and shunt resistors can be arranged in a separate housing region of the overload relay from the bimetals. This minimizes the mutual thermal influence and keeps the overload tripping characteristic unchanged.
• Pel RBimetaii * (16A) 2 + Rparallel * (7A) 2 , (6)
• the bimetallic current branch and the parallel-current branch are accommodated in a common housing section.
• the parallel resistor can be dimensioned with a smaller resistance than mentioned above, since the resulting reduced heating power on the bimetal can be compensated by a certain additional heating on the part of the parallel resistor, ie by radiation and convection.
• contacts with pluggable and / or rotatable contact carriers can be present. As a secondary function of the pluggable contact carrier, it interrupts the control contacts of the overload relay in the disassembled state with suitable actuating elements. This ensures that the overload relay and the monitoring of this monitored switching device is disabled, as long as the plug-in contact carrier is not mounted.
• auxiliary tool such as screwdriver or the like may be required for mounting the plug-in contact carrier auxiliary tool, such as screwdriver or the like may be required.
• the three contact elements can be integrated in a common, rotatable contact carrier.
• the rotational position of the contact carrier can be latching, so that predetermined rotation angle are maintained, in which the
• control contacts of the overload relay can be interrupted or not interrupted in predefined rotational angle positions, so that the overload relay is only ready for operation when correctly set.
• bimetallic branch with parallel current branch according to Figure 2 is a partial bridging of the heating element to realize the Weiteinstell Symposiumes possible.
• Suitable contacts for switching off the Weiteinstell Anlagenes are mountable contact elements which have smaller contact resistance at higher contact forces and can carry the full power with limited short-circuit currents.
• the contact resistance should be less than 1 m ⁇ so that most of the current flows across the bypass current path and only a small portion flows across the bridged bimetallic section. As a rough estimate, the residual heat output of the bridged section will compensate for heat dissipation by the bypass current conductor connected to the heater coil.
• the remaining heating conductor is up to a relative proportion of (16/23) 2 0.5, is not bridged to bridge.
• Figures 4 and 5 illustrate the principle of a power adjustment:
• the jointly highlighted field characterizes the thermal coupling between the bimetallic branch and parallel branch:
• a bimetal 11 and a heating element 12 in the main branch 1 and parallel shunts or heating conductors in the parallel branch 2 are present.
• the tapping of a coil 40 for a so-called n-trigger is present.
• the default setting range of an overload relay is between 11 and 16 A.
• the thermal power dissipation on the bimetal 11 must be constant in all adjustment ranges.
• Table 2 Setting range EB by shunt selection according to the principle of power adjustment
• FIG. 5 two heating conductors are arranged in parallel to the bimetal, wherein in FIG. 6, in addition, the short-circuit instant-out of FIG. 4 is present.
• FIG. 4 illustrates the principle of a power adjustment: The field highlighted in common indicates the thermal coupling between the bimetal branch and the parallel branch.
• a bimetal 11 and a heating conductor 12 in the main branch 1 as well as shunts or heating conductors connected in parallel in the secondary branch 2 are present.
• the tapping of a coil 40 for a so-called n-trigger is present.
• FIG. 5 two heating conductors are assigned in parallel to the bimetal, with the n-trigger from FIG. 4 additionally being present in FIG.
• FIGS. 7a, 7b and 7c alternatives for a thermal coupling of a winding 72 or shunts 73 or 74 of the parallel branch to a bimetal 71 without an original heating winding for the bimetal of the overload protection device 10 are shown in Figure 2: It results in a good thermal coupling.
• the bimetal 71 and the shunts 72, 73 and 74 are electrically isolated from each other, for example, by glass silk or mica.
• FIGS. 8a, 8b and 8c alternatives for a thermal coupling of the winding 72 or the shunt 72 or shunt 73 of the parallel branch to the bimetal with the original heating winding 76 for the bimetal 71 are shown: a good thermal coupling also results ,
• the heating conductor 76 is electrically insulated from the other current path components by glass silk or mica.
• the lower setting range and the upper setting range largely provide the same tripping characteristic.
• the short-circuit tripping characteristic 92 is additionally shown in FIG.
• the short-circuit tripping characteristic 92 is generally indicated as a multiple of the upper limit of the selected range.
• a constant short-circuit tripping characteristic 92 of the lower and the upper adjustment range can be adjusted by
• FIG. 11 shows a three-pole switch 100 with switching mechanism 101, three switching contacts 110, 110 ', HO "and associated overload triggers.
• electrothermal overload releases 102, 102 ', 102 on the one hand and electromagnetic short-circuit releases 103, 103', 103" on the other hand.
• the electrothermal actuators 102, 102 ', 102 “comprise bimetals in the current branch and connectable parallel-current branches with resistors and switches according to FIG. 1 or one of the further different examples of FIGS. 2 to 10.
• the parallel-current branches are produced by a mechanical actuation 105 with associated 'on / off' indicator manually switched on or off, which - as described in detail above - the Weiteinstell Berlin is created.
• An automated setting of the respective area is also possible.
• the bimetal 11 with heating element 12 each have a further heating coil 21 is assigned directly, so that thus results in the thermally coupled unit.
• the solenoid coil 40 of the short-circuit rapid release is tapped by the heating conductor 21 connected in parallel.

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• Emergency Protection Circuit Devices (AREA)
• Thermally Actuated Switches (AREA)
• Breakers (AREA)

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ID=37946267

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• 2006
  • 2006-01-23 DE DE102006003124A patent/DE102006003124A1/de not_active Withdrawn
• 2007
  • 2007-01-23 EP EP07702957A patent/EP1977436A1/de not_active Withdrawn
  • 2007-01-23 CN CN2007800029949A patent/CN101371325B/zh not_active Expired - Fee Related
  • 2007-01-23 US US12/223,030 patent/US20110248815A1/en not_active Abandoned
  • 2007-01-23 WO PCT/EP2007/000547 patent/WO2007082775A1/de active Application Filing
  • 2007-01-23 BR BRPI0707212-0A patent/BRPI0707212A2/pt not_active IP Right Cessation
  • 2007-01-23 JP JP2008550701A patent/JP4705999B2/ja not_active Expired - Fee Related

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