CN204007942U - The linear tester in oil temperature loop - Google Patents
The linear tester in oil temperature loop Download PDFInfo
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- CN204007942U CN204007942U CN201420456005.0U CN201420456005U CN204007942U CN 204007942 U CN204007942 U CN 204007942U CN 201420456005 U CN201420456005 U CN 201420456005U CN 204007942 U CN204007942 U CN 204007942U
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- 238000003379 elimination reaction Methods 0.000 abstract description 6
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- 238000001514 detection method Methods 0.000 abstract description 4
- 238000012360 testing method Methods 0.000 description 22
- 230000007423 decrease Effects 0.000 description 6
- 230000003247 decreasing effect Effects 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 238000012795 verification Methods 0.000 description 3
- 238000013461 design Methods 0.000 description 2
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- 238000005516 engineering process Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
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Abstract
The utility model discloses the linear tester in a kind of oil temperature loop, comprise three resistance output terminals, main resistor, temperature driving switch group and two inching switch groups; Two resistance output terminals connect with shorting stub, between one of them resistance output terminal and the 3rd resistance output terminal, are serially connected with main resistor, temperature driving switch group and two inching switch groups.The utility model adopts three resistance output terminals, and wherein two can be carried out short circuit by the loop resistance in tested loop with the resistance output terminal that shorting stub connects, and get rid of error interference, improve accuracy of detection; Be serially connected with between two resistance output terminals of resistance master and rotary switch, provide 0 DEG C ~ 100 DEG C according to Pt100 resistance value calibration table between equivalent multiple measured resistance value, detect to contrast whether differentiate measurand temperature variation normal.The utility model stable performance, easy and simple to handle, the linearity is good.Application of the present utility model has significantly improved temperature of oil in transformer defect elimination efficiency.
Description
Technical field
The utility model relates to a kind of tester, particularly the linear tester in a kind of oil temperature loop.
Background technology
In temperature of oil in transformer (comprising body oil temperature and winding oil temperature) defect elimination process, providing of thermal resistance standard signal is the key of oil temperature defect elimination, plays vital effect for the linearity verification of finding fault and oil temperature loop.Generally provide thermal resistance signal with rheochord, resistance box at present.This type of scheme has two drawbacks: the first, frequently calculate or consult resistance value R corresponding to calibration table oil temperature T, then continuous adjusting resistance case.This method is directly perceived not, quick, has increased the intensity of work on the spot, has extended the time of oil temperature defect elimination, is unfavorable for quick investigation and the elimination of defect.Second, resistance signal error is larger, because every variation 0.385 Ω of resistance, oil temperature just changes 1 oC, but common rheostat or resistance box permissible error are substantially all greater than 0.5 Ω (being 1oC ~ 2oC left and right), and the detection in on-the-spot oil temperature loop is made a big impact.
Utility model content
It is high, easily and can realize the linear tester in oil temperature loop of loop linearity test that the purpose of this utility model is to provide a kind of reliability.
The linear tester in this oil temperature loop that the utility model provides, comprises three resistance output terminals, main resistor, temperature driving switch group and two inching switch groups; Two resistance output terminals connect with shorting stub, between one of them resistance output terminal and the 3rd resistance output terminal, are serially connected with main resistor, temperature driving switch group and two inching switch groups.
A described resistance output terminal with shorting stub connection is connected with an inching switch group by main resistor, and this inching switch group is connected with temperature driving switch group, and this temperature driving switch group is connected with the 3rd resistance output terminal by another inching switch group.Described temperature driving switch group comprises temperature driving switch and the first resistive module; The moving contact of temperature driving switch is connected with the first resistive module.Described inching switch group comprises inching switch and the second resistive module; The moving contact of inching switch is connected with the second resistive module.Described temperature driving switch adopts 10 gear rotary switches; Described the first resistive module comprises that 5 resistances are that the resistance of 3.9 ohm and 5 resistances are resistance or the equivalent resistance of 3.8 ohm; Resistance or the equivalent resistance interleaved series of different resistances join.Described temperature driving switch adopts 5 gear rotary switches; Described the first resistive module comprises that 5 resistances of joining of being one another in series are resistance or the equivalent resistance of 7.7 ohm.Described inching switch adopts 10 gear rotary switches; Described the second resistive module comprises that 10 resistances of joining of being one another in series are resistance or the equivalent resistance of 0.1 ohm.The initial position of the moving contact of described inching switch accesses whole the second resistive module; This moving contact often changes a gear, reduces the described resistance of 0.1 ohm or equivalent resistance; When this moving contact goes to final gear, this second resistive module is by short circuit.Initial position short circuit second resistive module of the moving contact of described inching switch; This moving contact often changes a gear, increases the described resistance of 0.1 ohm or equivalent resistance; When this moving contact goes to final gear, this second resistive module all accesses.Described main resistor adopts resistance or the equivalent resistance of 99 ohm.
The utility model is to supply with instrument according to the portable thermal resistance standard signal of the rule design of resistance linear change along with measured temperature variation of Pt100 resistance; Adopt three resistance output terminals, wherein two can be carried out short circuit by the loop resistance in tested loop with the resistance output terminal that shorting stub connects, and get rid of error interference, improve accuracy of detection; Be serially connected with between two resistance output terminals of resistance master and rotary switch, provide 0 DEG C ~ 100 DEG C according to Pt100 resistance value calibration table between equivalent multiple analog electrical resistances, detect to contrast whether differentiate measurand temperature variation normal.The utility model stable performance, easy and simple to handle, the linearity is good, and can locate fast oil temperature circuit defect and the disposable test oil temperature loop linearity, solve the problem that oil temperature loop errer is large, accuracy rate is not high, thereby significantly improved temperature of oil in transformer defect elimination efficiency.
Brief description of the drawings
Fig. 1 is theory diagram of the present utility model.
Fig. 2 is panel schematic diagram of the present utility model.
Fig. 3 is a kind of circuit theory schematic diagram of the present utility model.
Fig. 4 is another kind of circuit theory schematic diagram of the present utility model.
Embodiment
As shown in Figure 1, the utility model comprises three resistance output terminals, main resistor, temperature driving switch group and two inching switch groups.Two resistance output terminals connect with shorting stub, in the two, between any one resistance output terminal and the 3rd resistance output terminal, are serially connected with main resistor, temperature driving switch group and two inching switch groups.
Two inching switch groups of the present utility model are respectively fine setting and increase progressively switches set and the fine setting switches set of successively decreasing.
Between main resistor, temperature driving switch group and two inching switch groups, join as long as being one another in series, no matter how the series sequence of these functional modules changes, and does not all affect implementation result of the present utility model.Consider from simple operation, the utility model adopts guidance panel distribution form as shown in Figure 2 to be implemented.Between resistance output terminal R1 and resistance output terminal R2, be connected with shorting stub, resistance output terminal R2 is connected by main resistor and the fine setting switches set of successively decreasing, fine setting is successively decreased and is increased progressively switches set with fine setting after switches set series connection temperature driving switch group and is connected, finely tunes to increase progressively switches set and be connected with resistance output terminal R3.
Resistance output terminal R1 of the present utility model, resistance output terminal R2, resistance output terminal R3 are resistance three-wire system output terminal; Between resistance output terminal R2 and resistance output terminal R3, export Pt100 thermal resistance value signal.
According to the linearity quality of PT100 output resistance resistance, temperature driving switch group of the present utility model can adopt the embodiment of multiple different gears.Changing in gear, only need to adjust the resistance that is connected with temperature driving switch or the resistance of equivalent resistance.
The utility model has also been equipped with 3 with p-wire.
Below respectively taking temperature driving switch group as 10 grades and temperature driving switch group as the specific embodiment of 5 grades is described further the utility model.
Embodiment mono-: the utility model provides 10 analog electrical resistances equivalent between 0 DEG C ~ 100 DEG C.
As shown in Figure 3, the utility model comprises that successively decrease switch S 1, temperature driving switch S2, fine setting of resistance output terminal R1, resistance output terminal R2, resistance output terminal R3, main resistor, fine setting increases progressively switch S 3, the first resistive module and two the second resistive module.Resistance output terminal R1 is connected with resistance output terminal R2 by shorting stub.After resistance output terminal R2 series connection main resistor, be connected with the successively decrease stationary contact of switch S 1 of fine setting, its moving contact is connected with the stationary contact of temperature driving switch S2 by the second resistive module, the moving contact of temperature driving switch S2 is connected with the stationary contact that fine setting increases progressively switch S 3 by the first resistive module, and the moving contact that this fine setting increases progressively switch S 3 is connected with resistance output terminal R3 by the first resistive module.
Between resistance output terminal R1 and resistance output terminal R2, be connected with shorting stub, object is by the loop resistance short circuit of test line or equipment under test, prevents that it from affecting precision of the present utility model.
Temperature driving switch S2 can adopt the rotary switch of 10 gears.Supporting ground, the first resistive module comprises that 5 resistances are that the resistance of 3.9 ohm and 5 resistances are resistance or the equivalent resistance of 3.8 ohm; The resistance of these different resistances or equivalent resistance interleaved series join.
The moving contact of temperature driving switch S2 in the time of initial position, not place in circuit of the first resistive module; This moving contact in the time of 0 DEG C of gear, 3.9 Ω resistance in the first resistive module or equivalent resistance place in circuit, output resistance resistance increases by 3.9 Ω; This moving contact is in the time of 10 DEG C of gears, 3.9 Ω resistance in the first resistive module or equivalent resistance and 3.8 Ω resistance or equivalent resistance series connection place in circuit, output resistance resistance is now this moving contact many 3.8 Ω in the time of 0 DEG C of gear, by that analogy, when this moving contact is during in " 100 DEG C " gear, the each resistance of the first resistive module place in circuit of all connecting.Along with increasing progressively step by step of this temperature driving switch selected gear, resistance or the equivalent resistance of the place in circuit of connecting in the first resistive module also increase progressively one by one, and corresponding output resistance resistance also increases gradually; Vice versa.
The fine setting switch S 1 of successively decreasing can adopt the rotary switch of 10 gears.The second resistive module can adopt and comprise that 10 resistances of joining of being one another in series are resistance or the equivalent resistance of 0.1 ohm.
Fine setting is successively decreased the moving contact of switch S 2 in the time of initial position, 10 resistance or the whole places in circuit of equivalent resistance in the second resistive module; This moving contact in the time of " 0.1 " gear, nine 0.1 Ω resistance in the second resistive module or equivalent resistance series connection place in circuit, output resistance resistance reduces by 0.1 Ω; This moving contact is in the time of " 0.2 " gear, eight 0.1 Ω resistance in the second resistive module or equivalent resistance series connection place in circuit, output resistance resistance is now this moving contact few 0.1 Ω in the time of " 0.1 " gear, by that analogy, when this moving contact is during in " 1.0 " gear, not place in circuit of the second resistive module.Along with this fine setting increasing progressively step by step of switch selected gear that successively decrease, resistance or the equivalent resistance of the place in circuit of connecting in the second resistive module successively decrease one by one, and output resistance resistance but reduces gradually; Vice versa.
Fine setting increases progressively switch S 3 and can adopt the rotary switch of 10 gears.The second resistive module can adopt and comprise that 10 resistances of joining of being one another in series are resistance or the equivalent resistance of 0.1 ohm.
Finely tune the moving contact that increases progressively switch S 3 in the time of initial position, not place in circuit of the second resistive module; This moving contact is in the time of " 0.1 " gear, 0.1 Ω resistance in the second resistive module or equivalent resistance place in circuit, this moving contact is in the time of " 0.2 " gear, two 0.1 Ω resistance in the second resistive module or equivalent resistance series connection place in circuit, output resistance resistance is now large when " 0.1 " gear compared with this moving contact, by that analogy, when this moving contact is during in " 1.0 " gear, the each resistance of the second resistive module place in circuit of all connecting.Along with this fine setting increases progressively increasing progressively step by step of switch selected gear, resistance or the equivalent resistance of the place in circuit of connecting in the second resistive module also increase progressively one by one, and corresponding output resistance resistance also increases gradually; Vice versa.
The utility model can obtain by adjusting above-mentioned switch the corresponding output resistance resistance of 10 temperature gears, in table one.
Table one:
| Sequence number | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Temperature DEG C | 0 | 10 | 20 | 30 | 40 | 50 | 60 | 70 | 80 | 90 | 100 |
| Resistance value Ω | 100.00 | 103.85 | 107.70 | 111.55 | 115.40 | 119.25 | 123.10 | 126.95 | 130.80 | 134.65 | 138.50 |
Embodiment bis-: the utility model provides 5 analog electrical resistances equivalent between 0 DEG C ~ 100 DEG C.
As shown in Figure 4, the utility model is the rotary switch of 5 gears by temperature driving switch on the basis of embodiment mono-; Accordingly, the first resistive module replaces with and comprises that 5 resistances of joining of being one another in series are resistance or the equivalent resistance of 7.7 ohm.
The wiring of the wiring of temperature driving switch S2 and embodiment mono-temperature driving switch is similar.When the moving contact of this temperature driving switch is during in initial position, not place in circuit of the first resistive module; This moving contact in the time of 0 DEG C of gear, 7.7 Ω resistance in the first resistive module or equivalent resistance place in circuit, output resistance resistance increases by 7.7 Ω; This moving contact is in the time of 20 DEG C of gears, 7.7 Ω resistance in the first resistive module or equivalent resistance and 7.7 Ω resistance or equivalent resistance series connection place in circuit, output resistance resistance is now this moving contact many 7.7 Ω in the time of 0 DEG C of gear, by that analogy, when this moving contact is during in " 100 DEG C " gear, the each resistance of the first resistive module place in circuit of all connecting.Along with increasing progressively step by step of this temperature driving switch selected gear, resistance or the equivalent resistance of the place in circuit of connecting in the first resistive module also increase progressively one by one, and corresponding output resistance resistance also increases gradually; Vice versa.
The utility model can obtain by adjusting above-mentioned switch the corresponding output resistance resistance of 5 temperature gears, in table two.
Table two:
| Sequence number | 1 | 2 | 3 | 4 | 5 | 6 |
| Temperature DEG C | 0 | 20 | 40 | 60 | 80 | 100 |
| Resistance value Ω | 100.00 | 107.70 | 115.40 | 123.10 | 130.80 | 138.50 |
Be not difficult to find out from table one and table two, when the utility model designs enforcement according to the mode of embodiment mono-, the linearity of output resistance is better than the mode of pressing embodiment bis-.
When use, according to the layout of Fig. 2, operation steps of the present utility model is as follows:
The first step, calibration.By fine setting increase progressively switch "+", fine setting successively decrease switch "-", temperature driving switch " DEG C " be all threaded to " 0 " position, whether reach 100 ohm with the resistance value that High Precision Multimeter small resistor gear is checked between jack R2 and jack R3; To go to next step; No, be used in conjunction with adjustment fine setting and increase progressively switch "+", finely tune the switch "-" that successively decreases, until the resistance value between jack R2 and jack R3 reaches 100 ohm.
Second step, jack R1 of the present utility model, jack R2, jack R3 are inserted respectively in three p-wire one end, terminals R1, terminals R2, the terminals R3 of other end access test line or equipment under test, and by temperature driving switch " DEG C " be threaded to respectively " 10,20,30,40,50,60,70,80,90,100 " gear, obtain its local oil temperature data;
The 3rd step, obtains the distant place oil temperature data of test line second step or equipment under test from background computer, and relatively whether the numerical value of the two is consistent, or whether its deviation is in allowed band.
Suppose the difference≤N DEG C of the local oil temperature of regulation and distant place oil temperature, if the difference≤N DEG C of the local oil temperature of this test line or equipment under test and its distant place oil temperature judges that this test line or equipment under test are normal.If the difference > N DEG C of the local oil temperature of this test line or equipment under test and its distant place oil temperature, judges this test line or equipment under test fault.
In operating process, provide analog electrical resistance by the utility model, be used in conjunction with by multimeter and the utility model, to determine whether fault of test line or equipment under test.
Whether the utility model in use can be used for checking the oil temperature loop linearity simultaneously good.Temperature driving switch is started to increase progressively one by one from " 0 " shelves, until " 100 " shelves, see that whether the local oil temperature of current tested circuit or tested equipment and the difference of distant place oil temperature be constant, if along with the continuous increase of temperature gear, the difference of its local oil temperature and distant place oil temperature is fixed value or changes little (not exceeding specified value), shows that the linearity of current tested circuit or tested equipment is good; If in testing process, the local oil temperature of current tested circuit or tested equipment and the difference of distant place oil temperature are increasing, show the poor linearity of current tested circuit or tested equipment, also can judge this test line or equipment under test fault.
According to the method described above, the utility model can be used for oil temperature loop (secondary circuit), transmitter, measure and control device and background computer Defect Search and and oil temperature loop linearity detection in electric system.
Secondary circuit checks: utilize the resistance value signal source that the utility model provides to carry out verification to secondary circuit, judge that whether oil temperature loop is normal.
Specific practice: the analog electrical resistance providing at oil thermometer output terminal input the utility model, in whether normal delivery of this analog electrical resistance of input end measuring of transmitter.If normal, enter next step treatment scheme; If undesired, investigate method by segmentation, investigate out and have the secondary circuit of fault and carry out fault handling.
Transmitter checks: utilize resistance value signal source to carry out verification to transmitter, confirm that whether oil temperature loop is normal.
Specific practice: the analog electrical resistance providing at input end input the utility model of transmitter, whether the voltage (or electric current) of measuring transducer output is normal.If normal, enter next step treatment scheme; If undesired, be defined as transmitter fault.
Measure and control device and background computer inspection: if the said equipment and circuit all do not detect fault, be defined as measure and control device and background computer fault.
The utility model can be located oil temperature circuit defect, the disposable test oil temperature loop linearity fast, efficiently solves the problem that oil temperature loop errer is large, accuracy rate is not high.
Claims (10)
1. the linear tester in oil temperature loop, is characterized in that, comprises three resistance output terminals, main resistor, temperature driving switch group and two inching switch groups; Two resistance output terminals connect with shorting stub, between one of them resistance output terminal and the 3rd resistance output terminal, are serially connected with main resistor, temperature driving switch group and two inching switch groups.
2. the linear tester in oil temperature according to claim 1 loop, it is characterized in that, a described resistance output terminal with shorting stub connection is connected with an inching switch group by main resistor, this inching switch group is connected with temperature driving switch group, and this temperature driving switch group is connected with the 3rd resistance output terminal by another inching switch group.
3. the linear tester in oil temperature according to claim 1 loop, is characterized in that, described temperature driving switch group comprises temperature driving switch and the first resistive module; The moving contact of temperature driving switch is connected with the first resistive module.
4. the linear tester in oil temperature according to claim 1 loop, is characterized in that, described inching switch group comprises inching switch and the second resistive module; The moving contact of inching switch is connected with the second resistive module.
5. the linear tester in oil temperature according to claim 3 loop, is characterized in that, described temperature driving switch adopts 10 gear rotary switches; Described the first resistive module comprises that 5 resistances are that the resistance of 3.9 ohm and 5 resistances are resistance or the equivalent resistance of 3.8 ohm; Resistance or the equivalent resistance interleaved series of different resistances join.
6. the linear tester in oil temperature according to claim 3 loop, is characterized in that, described temperature driving switch adopts 5 gear rotary switches; Described the first resistive module comprises that 5 resistances of joining of being one another in series are resistance or the equivalent resistance of 7.7 ohm.
7. the linear tester in oil temperature according to claim 4 loop, is characterized in that, described inching switch adopts 10 gear rotary switches; Described the second resistive module comprises that 10 resistances of joining of being one another in series are resistance or the equivalent resistance of 0.1 ohm.
8. the linear tester in oil temperature according to claim 7 loop, is characterized in that, the initial position of the moving contact of described inching switch accesses whole the second resistive module; This moving contact often changes a gear, reduces the described resistance of 0.1 ohm or equivalent resistance; When this moving contact goes to final gear, this second resistive module is by short circuit.
9. the linear tester in oil temperature according to claim 7 loop, is characterized in that initial position short circuit second resistive module of the moving contact of described inching switch; This moving contact often changes a gear, increases the described resistance of 0.1 ohm or equivalent resistance; When this moving contact goes to final gear, this second resistive module all accesses.
10. the linear tester in oil temperature according to claim 1 loop, is characterized in that, described main resistor adopts resistance or the equivalent resistance of 99 ohm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420456005.0U CN204007942U (en) | 2014-08-14 | 2014-08-14 | The linear tester in oil temperature loop |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420456005.0U CN204007942U (en) | 2014-08-14 | 2014-08-14 | The linear tester in oil temperature loop |
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| Publication Number | Publication Date |
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| CN204007942U true CN204007942U (en) | 2014-12-10 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201420456005.0U Expired - Lifetime CN204007942U (en) | 2014-08-14 | 2014-08-14 | The linear tester in oil temperature loop |
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| Country | Link |
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| CN (1) | CN204007942U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104101449A (en) * | 2014-08-14 | 2014-10-15 | 国网湖南省电力公司长沙供电分公司 | Linear oil temperature loop tester |
| CN106443187A (en) * | 2016-09-23 | 2017-02-22 | 江西洪都航空工业集团有限责任公司 | Temperature selector detection method |
-
2014
- 2014-08-14 CN CN201420456005.0U patent/CN204007942U/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104101449A (en) * | 2014-08-14 | 2014-10-15 | 国网湖南省电力公司长沙供电分公司 | Linear oil temperature loop tester |
| CN106443187A (en) * | 2016-09-23 | 2017-02-22 | 江西洪都航空工业集团有限责任公司 | Temperature selector detection method |
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Granted publication date: 20141210 |
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| CX01 | Expiry of patent term |