Some standard content:
Verification Regulation of DC Comparison Bridge
JJG 546-—1988
Verification Regulation of DC Comparison Bridge
Ferification Regulation ot
Jx:Comparison Iridge
J3G546—1988
4 This verification regulation was approved by the State Planning Bureau on March 22, 1988 and will be implemented on February 1, 1919. Responsible unit: National Institute of Technology
Drafting unit, China Testing Technology Research Institute The technical provisions of this regulation shall be interpreted by the drafting unit. The main drafters of this regulation:
Energy Production England, China Institute of Technology!
Participating drafter:
Park Yangyu (China Testing Technology Research Institute) 598
Technical requirements
Policy document -·
Calibration date
Calibration method
Processing of quick determination resultsCalibration period
Appendix 1 Derivation of comparison bridge formula
Appendix 2
Comparison bridge ratio ratio
3
Calculation of ratio (refer to table)
Appendix 4 Overall determination method
DC comparison bridge calibration procedure
This procedure is applicable to the calibration of newly manufactured and used DC comparison bridges (hereinafter referred to as comparison bridges). The regulations are not applicable to ordinary single and double loans. They are only used for the calibration of direct current bridges and true reading intermediate discharges. The comparative electric ruler is specially used for the calibration of direct current resistors such as direct current transformers and direct current test boxes. The principle circuit is shown in Figure 1. In the figure: R.-micro-electric bridge principle line diagram K-type transformer. Its break value: ~1
ratio resistance: 6~near plate 10×(10C0100101113.1101>to read the value and send M to an R
enter the An 10 (+, +3) or value flat plate:.
R—E example electricity, out of 5 ten let plate 10×.007160-10, 11 non 1-0.C1: the door starts the proportion; one has the United States, how to adjust the strong complaint mouth and, long superior place a strong rise, respectively back 1 and time intention can be used as much as possible, Limit type; Hr-outlet entertainment's beauty
CP-P.(—or measuring current crown R, current and potential terminal E;,,, external standard current limit width
(: large standard area:
: 2—respectively open 1, (or 2, 2" long resistor:, ratio, limit, wind simple difference, respectively to the potential, 60)
The puncture resistor adopts the four-terminal vanadium method to connect to the measured R, and is compared with the built-in reference resistor R of the standard bridge arm to form an external narrow resistor: another In addition, the two bridge resistors Rz and Rz are directly proportional to each other, and in order to eliminate the error of the bridge resistors Rz and Rz, a replacement switch K is designed in the circuit. By passing Rz and Rz, the value of the equal balance plate is realized, and the compensation setting error is achieved when the ratio Rz is 1:1. In order to eliminate the reading error (RR:10), the 10 positive electrodes of the 2I<8 type comparison plate are adjusted to the same value by fine-tuning the circuit. In this case, the ratio Kz=1:10 is said to be different. Reduce to the level that can be imagined: XQ7 type light comparison bridge with reference resistor and M: six 10002 discs are insufficient for fine-tuning the drill material, the reference resistor error and the error of the comparison arm value are corrected in the calculation column: in the same comparison bridge test, the measured error is only in the sample, the open circuit and the medium are twisted in at the same time, without the lead wire. The resistance is tested by the component, ensuring the consistency of the test state and the actual use state. The balance equation of the single circuit can be expected:
R, R Rit1+a) - KiFs(1 -5 + a +on)RH + ) = KRnt -+1 - )
In the formula: - measured loss nominal value;
RNH - reference resistance nominal value;
K - ratio nominal value:
"adjust the reference value when adjusting the balance relative to 10 - measured loss correction value relative to the nominal value: reference resistance correction value relative to the nominal value; % - ratio correction value relative to the nominal value. Formula (1) is the correction value table of XQ type output bridge measuring telecommunication, of which 6. The values of and are obtained at regular intervals every year, and the bridge is used to make corrections. Q48 type is a relatively large electric correction, with a built-in resistance scale: the 10 disks of the group and the scale are made to be fine-tunable, and the product can be adjusted to a certain degree by equal low balance and user adjustment technology. Then formula (1) is:
From formula (2), it can be known that the U48 type comparison bridge directly measures the measured resistance R, and the relative value of the measured resistance R. The QI18 type comparison bridge uses the built-in reference resistor and the proportional adjustment technique to make the measured resistance directly compared with the built-in reference resistor. The CI8 type comparison bridge and the Q17 type comparison bridge are the same, but the symbols of each bridge are different. Therefore, the formula is used. The symbols in this specification are all 148 type comparison bridge. Technical requirements
■ External and marking
【.1 The comparison bridge is marked on the label (on the female shell); 1.1.1 Product name, model and factory number:
1.1.2 Manufacturing! Or trademark:
1.1.3 Effective range and index of each range level; reference temperature and nominal use temperature: 1.1.4:
1.1.5 Relay voltage
1.1.6 Use position (the bridge is set to the smallest position; it can be used in any position) 1.2 The switches and terminals of the comparison bridge panel 1 should indicate the function and material card (when necessary) 2 The index, reference temperature and relative humidity range of the comparison bridge, the nominal use temperature and relative humidity range should comply with the provisions of Table 1.
3 The comparison bridge shall be used in accordance with the relevant temperature range. The allowable variation of the reference condition to the nominal condition shall not exceed the provisions of the table:
The allowable deviation is expressed as a percentage of the nominal value, No.
10F - 10
a0%-60%
40%-60%
Allowable gain (%)
Standard use fiber and allowable type difference
25 % -75%
25% - 75%
Tooth specific cattle
Rate (r)
20 = 2
20 = 5
20 + 3
401%-60%
Under the test voltage of 5V±10%, the value measured between any of the most sensitive buttons and any other small accessible points connected to the circuit shall not exceed 5M1. The measurement of the standard voltage shall be carried out between 1mⅡ and 2mil with the test voltage applied. The deviation caused by any connection to the external or earth connection shall not exceed 10% of the basic error limit. When performing this shear test, if the casing is conductive, it shall be placed flat on the conductive surface. If the casing is made of suitable materials, the bridge shall be placed flat on the conductive surface. The insulation strength between the circuit and the casing and any conductive parts that are not electrically connected to the circuit shall be able to withstand the short-circuit test of 500V±1% of the equivalent AC medium voltage of 45-65Hz for 1min without breakdown or flying phenomenon. The built-in resistor R group is composed of 1%, 10:0020, 1000C, 00000, which meets the requirements of the 6
DC standard resistor calibration temperature range 3J16-19641. The built-in resistor of the XQ type light bridge is an unadjustable fixed resistor. This bridge has an external standard group: C148 type relatively corrected built-in resistor with an inductance of 0.02%, a strict regulation range of 1.001%, 602
This circuit has an external standard resistor button:
? Q148 type ratio converter has an external standard seven-output button. When in use, the connection resistance of the connected P system should be less than o.tm5n
load bridge ratio report 2 (M2 is composed of 6 decimal plates 10× (1000+10011+【+0.110.01). For M, the annual change of each resistor is required to be less than 0.510-, and the difference between the resistance temperature coefficients is less than 5× 10-h element: These 10 resistors should have the ability to connect components for verification, X package type is relatively large proportional resistor, non-adjustable, light type is relatively small, the resistors of the disk can be adjusted: 2%, adjustment group Hui%.
Comparison of self-bridge proportional group M2, but the list, the allowable error should not exceed the provisions of Table 3: Table 3
Resistance
7×10-4
3.5×1n-s
The internal connecting wire output resistance r2 of the comparison bridge and the connection resistance of the switch K are as small as possible, requiring 0
r+r'r2+r20.010 and r +ri + [M,r, -r+- (M)n0,020 three test objects
1 When testing the basic table difference of the comparison bridge, it should be carried out under the test temperature and phase change conditions specified in Table 2. 12 The measurement of the insulation resistance of the comparison bridge and the test of the voltage should be carried out under the following on-site conditions: Environmental pollution [5~35t: humidity within the range of (45-75)%: no phosphorus water, freezing, condensation, rain, sunlight, etc. 13.1 The uncertainty of the determination and adjustment of the reference resistance of the comparison bridge shall meet the requirements of the relevant standard data of the standard resistor.
13.2 The uncertainty of the determination and adjustment of the ratio K of the comparison bridge shall not exceed 1/10 of the value of the tested resistor. For the comparison of the same nominal resistance of 10009, the comparison uncertainty shall not exceed 1/20 of the value of the test bridge.
14 When determining the basic technical error of the comparison bridge, refer to the requirements of the standard of the current bridge control. 15 The uncertainty and allowable error of the comparison electrode ratio resistance M1, M2, and M3 are shown in Table 1. Table 4
Insufficient time
5×-s
5×10-
3×10-?
Chemical value
×in-:
1× n-
Allowed assumption
5×10-1
1×10-1wwW.bzxz.Net
12:10-3
1x10-2
1×10-1
For this device measuring the insulated conductor, the measured voltage is 50V and the measurement uncertainty is less than =20%. 16
The voltage test bench used for the pressure test shall have sufficient output capacity (10V1) and adjustable voltage. Four test items
Comparison test of the converter shall be carried out according to the provisions in Table 5. 5
Pregnancy light room
Test items
Outer general
Original
Chronic acid
Inner leaf life stroke
Comparison lock K
North example stomach M, m::
\x-r+ (M,)n
Appearance inspection
Five test methods
Use visual inspection to check the markings on the comparison bridge or the outer surface, which shall meet the technical requirements. For the newly produced comparison bridge, it is required to be intact. For the comparison after use and maintenance, if there are defects that affect the performance of the bridge, they should be repaired and re-calibrated. 20
Line test: Use the data of the meter to check and compare the load circuit: When it is found that there is more than normal, the reason should be clarified and the test can be carried out after the sample is restored. The insulation resistance is measured by commercial resistance tester or network image tester and the test adjustment method is used to measure the insulation resistance. If the lifetime limit cannot meet the requirements, the reason should be clarified and the test should be carried out after the test is completed. 22
The withstand voltage test is carried out on the high voltage test bench. The test voltage is steadily increased at a rate of 0V to the specified test voltage. The withstand voltage test lasts for 1min and there is no breakdown or arc phenomenon. It is qualified, otherwise it is unqualified. Then lower the voltage steadily to 23°C. The calibration and adjustment of the reference voltage is carried out before and after the adjustment. The calibration value before adjustment is used to observe the change, and the calibration value after adjustment is used as the calibration result. After the adjustment, the voltage must be stable for comparison. Only one calibration is carried out. The reference resistor and the calibration bridge are connected, and the calibration is carried out according to the method of the standard resistor J3166-19&second-class standard device.
To adjust the reference resistance in the (46) proportional light panel: loosen the octagonal screw with a special wrench, move the potentiometer shaft with a screwdriver until it reaches the desired setting, and finally tighten the six-nut with a hand, 634
Figure? Proportional bridge: Principle of proportional disk calibration (bridge number selection
Comparison R: Select 10 as the reference resistance: 24 Ratio 2: 2, and 2, calibration
24.1 Decimal substitution
24.1.11 Principle of the proportional substitution method
Use The 10 step resistances of the rear disk are the same as the step resistances of the previous disk. The 10 small step resistances of the rear disk are marked by the second-class standard resistors. The actual value of each step resistance of the previous disk is calculated. The step resistance of each ten-step resistor of the next disk is determined by the galvanometer.
24.1.2 Control circuit
u, the original circuit diagram of the calibration proportional disk Mz is shown in 2
, and the K switch is set to 1.
b. Calibrate the reading disk M, and The principle circuit of the value level disk t1 is shown in Figure 2, K can be set to vacant 2.
24.1.3 Example disk Mz is calibrated within 7
24,1.3.1M.: 1000 disk grabbing process measurement arm R: selected as. E number or gate. 02 grade resistance box × 1.000 disk: R: send M, display tracking treatment (→999 through, 10 disk music value stomach S, its close empty etc.; switch K,, K, are set to 1:
in the comparison bridge proportional arm 2 1: edit to enter 10Q second-class standard resistor R, [2] calibration step reward || tt||1. Set all decimal values of M1 to zero, set the value of R1×10000 to 1, and the values of other decimal values to 0. Turn on switch K1, connect port E, adjust M2, make the bridge balanced, and record the value of M2 as cb. Do not turn off K. After that, adjust M1 to make the bridge flat, and record the value of M2 as R2! Compare the values of standard resistor R1,
The above steps are compared with 1. The difference between the ten step values of M1 and 000 is:
SR!-R1-
-to(l -a,)
R -o-kt a,)
. Return the M,×100% display value 11 to zero, and the M,×13 display value from more than 1, two steps, so that the good and bad balance, the display value of the table M is! ,
Step b. The first resistance element value of the M,10301 disk is compared with the M,×[002 with 1 step, the power supply of the electrical standard stops, and the electrical indication position of the ten moves at the same point is checked. The difference is:
o(ar-)
RI - 2r! +af =R+ia(a/ -e)
. Send the ×0000 dial value 1 to 2, × dial value advances from 1 to 1, M dial value is still! , adjust M to make the electric grab balanced, record M to make the average value! E. The indication of the M,×1000 disk is 10 and the indication of the 1 disk is 2. Adjust M to make the voltage balanced, record the balanced indication of M, and compare the second resistance element value R of the M,×1000 disk with the 1 step voltage value R of the M,×0D disk. The difference is:
2R!- -R+(a-b2 +1
+(61 -u)
, and get:
(ai-6)
Al - rl - Zr! -+
Accumulate and get:
Among them:
ERI+AI-MR!-
ZR =+R!+Z
-a,, =
SRE = R
(atbl)
24.1.3.2 Verification of M layer islands
【Parameters of electric correction screen: refer to Table 6
+× 10G
Mj 10t, mt 5
M: 10, m1: 3
M:1 10, : 0
M: 102, : 0
: Ia, shy 5
5× 10
n:jx10
M:fx10
Mi:fxi
Mzt FxU !
5t2:J*++0.01
(2) For M; the second, the fourth, and the fourth are determined, similar to the first plate. Example: In the middle, the ≥R! is connected to the sequence replaced by R\, recognize the calculation formula of the measured resistance value, and determine the second recorded data.
From the table, the actual value formula of the second dose is; the reading effect of
is shown in the table
. A calculation formula
S=RF = (al 5>, E-A+f
There is a measured actual raw material
e calculation formula
to R[ =2×rP+[
SR-RP+S
-RF-HF- U) UnF-At?RPR!-
=R -(a ) R- Mn=9xs!
3%-K!-芸k! (n- R-SrI+h
+-This is the second consistent calculation formula, in total, year! (S? aF), ]-(ab19)
South(a#-6y
By analogy, the third island resistor decision pin calculation formula is: +
Where:
= (a -6l)
The actual value of the fourth resistor is calculated by the formula: RRY
af =m(ar f)
The calculation formula of the actual value of the resistance of the first plate is: SRY
Su ZRY
00g(-6)
(3M, the last plate of the step resistance can be verified by the galvanometer deflection method, that is, change the value of the last plate by 1, so that the galvanometer deflects 10 grids, and record the number of deflection grids of the galvanometer for each change of one step resistance: The calculation formula of the correction value of the resistance of the technical plate is:
24.1.4M, mrt) verification process
a. Set the switch K to the 2 position, and count on M, and the verification method is completely the same as that of M. b. The verification of the following plates can be carried out in the same way as the M×10 plates, and compare the internal connection wires of the grid, the switch contact resistance: Verification of the indication of each plate 25.1 Measure r 1 (M2 resistance
25.1.1 Circuit and parameters
Determination++(M) The principle circuit diagram of resistance is shown in Figure 3, (13)
Use the measured voltage to correct the error, connect Ry to 1 product, test R, 002 level 101\ convex resistance, M, as the reading disk, all indications of M disk are set to zero, K, set to 1, K, set to 2. 25,1,2 Measurement process
Connect the galvanometer, adjust M, disk fast bridge balance, record M, disk balance indication M, then 11 one (electric drop value
r++ (M=x1-+()
25.2 Measure r--(M,) resistance
25.2.1 Line salary and special number
Control 2+2+"M2. The principle line of resistance is shown in Figure 4. Then measure +r+ (M) resistance principle line voltage
Figure 4 Measure F (M,) resistance point circuit diagram
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