Verification Regulation of Amperemeters Voltmeters Wattmeters and Ohmmeters
Introduction to standards:
This regulation applies to the initial verification, subsequent verification and in-use inspection of direct-acting analog indicating DC and AC (frequency 40Hz ~ 10KHz) ammeters, voltmeters, power meters and resistance meters (resistance 1∩ ~ 1M∩) and multimeters (hereinafter referred to as instruments) for measuring current, voltage and resistance. This regulation does not apply to the verification of automatic recording instruments, digital instruments, electronic instruments, average voltage meters, peak voltage meters, leakage current meters, three-phase power meters and electrostatic voltage meters with voltages higher than 600V. JJG 124-2005 Ammeter, voltmeter, power meter and resistance meter JJG124-2005 standard download decompression password: www.bzxz.net
This regulation applies to the initial verification, subsequent verification and in-use inspection of direct-acting analog indicating DC and AC (frequency 40Hz~10KHz) ammeters, voltmeters, power meters and resistance meters (resistance 1∩~1M∩) and multimeters for measuring current, voltage and resistance (hereinafter referred to as instruments). This regulation does not apply to the verification of automatic recording instruments, digital instruments, electronic instruments, average voltage meters, peak voltage meters, leakage current meters, three-phase power meters and electrostatic voltage meters with voltages higher than 600V.
Some standard content:
Shanhua People's Republic of China National Metrology Verification Regulation JJG124-2005
Amperemeters, voltmeters, power meters and resistance metersWoltmeters, Wattmeters and OhmmetersAmperemeters
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For participants only
2005-10-09 Release
2006-04-09 Implementation
State Administration of Quality Supervision, Inspection and Quarantine Issued JJG124-2005
Amperemeters, voltmeters, power meters
And resistance meter verification regulations
Verification Regulation of AmperemetersVoltmeters,Wattmeters and OhmmetersJJG 124—2005
Replaces JJG124--1993
This regulation was approved by the General Administration of Quality Supervision, Inspection and Quarantine on October 9, 2005, and came into effect on April 9, 2006.
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Responsible unit
Main drafting unit:
Participating drafting unit:
National Electromagnetic Metrology Technical Committee
Liaoning Institute of Metrology Science
Wenzhou Quality and Technical Supervision and Inspection Institute
This regulation entrusts the National Electromagnetic Metrology Technical Committee to be responsible for interpreting this regulation. Main drafters:
Cui Jihong
Sun Lihua
Wang Yueying
Participating drafters:
JJG124—-2005
(Liaoning Institute of Metrology Science)
(Liaoning Institute of Metrology Science)
(Liaoning Institute of Metrology Science)
(Wenzhou Quality and Technical Supervision and Inspection Institute )CAO
Network resources
For reference only
References·
Overview·
4Metering performance requirements
4.1Accuracy level
4.2Basic error
4.3Deviation from zero
4.4Position influence
4.5Power factor influence
5General technical requirements| |tt||5.1 Appearance inspection
5.2 Insulation resistance test
5.3 Dielectric strength test
5.4 Damping.
(Measuring instrument making
6.1 Verification conditions
6.2 Verification items F…
Verification method·
6.4 Processing of verification results,
6.5 Verification cycle
|Appendix Ax represents the basis
Appendix B Resistance meter calibration procedure 2
Appendix C Original record
Appendix D Instrument calibration certificate page format
JJG124—2005
Appendix E Instrument calibration result notification page format
(3)
(3)
1 Scope
JJG124—2005
Calibrating procedures for ammeters, voltmeters, power meters and ohmmeters This procedure applies to the initial calibration, subsequent calibration and on-site inspection of direct-acting analog indicating DC and AC (frequency 40Hz~10kHz) ammeters, voltmeters, power meters and ohmmeters (resistance 1Ω~1M0) and multimeters that measure current, voltage and resistance (hereinafter referred to as instruments). This procedure does not apply to automatic Calibration of recording instruments, digital instruments, electric instruments, average value positive meters, peak value meters, leakage current meters, phase power meters and electrostatic voltmeters with voltages above 600V. 2 References: JJF1001-1998 (recently used metrological terms and definitions), JJF1059-1999 "Assessment of measurement uncertainty", GB/T7676.1~7676.9-1998 "Direct-acting analog indicating electrical measuring instruments and their accessories". When using this procedure, attention should be paid to the use of the current valid versions of the above-mentioned referenced documents. 3 Overview: Network resources: The instrument is a scientific and technological product composed of a measuring load circuit and a measuring device. The measured object is converted into a base acceptable to the measuring mechanism through the measuring disk circuit, which drives the measuring machine to move, thereby preventing the person being measured from indicating the person being measured, etc.
Due to the different types of drive plates, commonly used instruments can be divided into micro-electric system, inductive system, electrodynamic system, electrostatic system and rectifier system. 4. Measurement performance requirements
4.1 Accuracy grade
The accuracy grade and maximum allowable error (i.e., reference error) of the instrument shall comply with the provisions of Table 1. Table 1 Accuracy grade and maximum allowable error Accuracy grade
Maximum allowable error (%)
Accuracy grade
Maximum allowable error (%)
4.2 Basic error
± (1,2
4.2.1 The basic error of the instrument shall not exceed the maximum allowable error specified in Table 1 for all graduation lines within the scale measurement range (effective range).
The basic error of the instrument is expressed as reference error and calculated according to formula (1): Where: X is the indicated value of the instrument;
X is the actual value of the measured value;
JJG 124—2005
1×100%
X, - reference value (reference values of various instruments are given in Appendix A), 4.2.2 Rise and fall variation
The rise and fall variation of the instrument should not exceed the absolute value of the maximum allowable error, calculated according to formula (2). -Xml
×100%
Where: X, and X are the actual values of the maximum rise and fall of the measured value at a certain point, respectively, and the meanings of and are the same as those in formula (1).
4.3 Deviation from zero position
For instruments with zero graduation line on the scale, a power-off recovery test should be carried out. 4.3.1 When the instrument is energized for 30s at the upper limit of the measuring range, the value being measured is quickly reduced to zero. Within 15s after power failure, the indicator deviation from the zero graduation line should not exceed 50% of the maximum allowable error, expressed as a percentage of the scale length. 4.3.2 For the power meter, only the voltage line is energized, and the indicator deviates from the zero graduation line. The change should not exceed 100% of the maximum allowable error.
4.3.3 The resistance meter deviates from zero position without network resources
4.4 Position influence
For instruments without water filling device and with signal bone mark, Tilt 5 degrees or the specified value in any direction from the standard position; for instruments without position marks, tilt 90 degrees, that is, horizontal or vertical position, the error change in the former should not exceed 50% of the maximum allowable error; the latter should not exceed 100%. 4.5 Power factor influence (applicable to power meters below) should be tested in both leading and trailing states, and the change in instrument error caused by this should not exceed 100% of the maximum allowable error.
5 General technical requirements
5.1 Appearance inspection
The instrument should be marked with the instrument name, manufacturing name (or trademark), factory number, matching mark and other information, general marks and symbols to ensure its correct use, and there should be no defects that may cause measurement errors and affect accuracy: 5.2 Insulation resistance measurement
The insulation resistance measured by applying a 500V DC voltage between all lines of the instrument and the reference test "ground" should not be less than 5MQ.
5.3 Dielectric strength test
5.3.1 All measuring circuits of the instrument and the reference test "ground" should be able to withstand the AC voltage test of a practical sine wave with a frequency of 50Hz. The breakdown current is 5mA and the duration is 1min. No breakdown or arcing should occur during the test. 5.3.2 The test voltage should be selected according to the nominal voltage of the instrument circuit and the value given in Table 2 (unless otherwise specified). 5.3.3 The current circuit and voltage circuit of the power meter are subjected to a dielectric strength test. The test voltage is twice the nominal voltage 2
, but not less than 50)V.
Nominal voltage of measuring line
(line insulation voltage) V
JJG 124—2005
Table 2 Test voltage
Insulation mark
(digital value)
Optical digital
Test voltage
(effective value)
Except for instruments with extended response time and other provisions in national standards, the instrument's resistance shall meet the following requirements 5.4.! Overshoot
For positions with a full deflection angle of less than 180°, the overshoot shall exceed 25%,
5.4.2 The time of response
shall not exceed 20% of the original length of the scale. Other instruments shall not be used only for reference.
Unless otherwise agreed between the manufacturer and the user, the instrument shall be suddenly subjected to a force that can make its indicator finally indicate the measured value at 2/3 of the length of the scale. After 4, when shall the indicator deviate from the final static position by more than 1.5% of the length of the scale.
6 Control of measuring instruments
Control of measuring instruments includes: initial verification, continuous verification and inspection during use. 6. Verification conditions
The basic error of the instrument shall be verified under the standard conditions specified in Table 3. Table 3 Standard conditions and allowable deviations of relevant influencing quantities Standard conditions
Influencing structure
Except for those marked otherwise
Ambient temperature
Relative swirl
DC measured ripple
Ripple content is zero
Verification allowable deviation
(applicable to single-standard)
Accuracy level
Equal to and less than (,2
40%-60% || tt||Ripple content 1%
Accuracy level
Equal to 0.5
40%~80%
Ripple content 3%
Affect
AC measured
AC measured frequency
Location?
Auxiliary power supply
External magnetic field
External electric field
Power factor
Standard conditions
JJG 124--2005
Table (continued)
Allowable deviation for verification
(applicable to a single standard value)\
Accuracy grade
Except those marked otherwise
451z~65Hz
Equal to and less than 0.2
Accuracy grade
筝十和人:0.5
Rectification coefficient of instruments and instruments using phase-shifting networks in measuring circuits The distortion factor is less than or equal to 1/2 of the accuracy grade or 1%, whichever is smaller:
2. For other instruments, the distortion factor shall not exceed 5% ±2% of the standard value
For fixed instruments, the mounting surface shall be vertical
Make portable instruments Note: (1) This allowable deviation is ±5% of the nominal value. 115% of the nominal value. 40A/m. Frequency from DC to 65Hz in any direction 1km. Frequency from DC to 65Hz in any direction. A single approved value or a single standard value specified by the manufacturer. No deviation is allowed from the standard range. When installing the level, the instrument should be adjusted to the maximum position (except for the unpermitted error specified by the manufacturer, ①) 40A/m is close to the highest value of the pool 5) After full (inductive) is the meal number, and over (capacitive) is the special number. 6.1.2 Requirements for standard equipment
6.1.2.1 When inspecting instruments, the expanded uncertainty of measurement (taken as 2) caused by the standard instrument, auxiliary equipment and environmental conditions should be less than 1/3 of the maximum allowable error of the instrument under inspection. 6.1.2.2 The power supply stability within 30% should not be less than 1/10 of the maximum allowable error of the instrument under inspection. 6.1.2.3 The regulator should ensure that the zero is adjusted to the upper limit of the instrument under inspection, and any individual component of the instrument can be adjusted smoothly and continuously. The adjustment fineness should not be less than 1/10 of the maximum allowable error of the meter under test. 6.1.2.4 The calibration device should have good shielding and grounding to avoid external interference. 6.2 Verification Items
The calibration items of the instrument are shown in Table 4.
6.3 Verification Methods
6.3.1 General Verification Provisions
6.3.1.1 The basic error of the meter under test should be verified according to its function, accuracy level, range and frequency. For the instrument used under multiple power supplies, each power supply should be connected for verification. It is also possible to inspect only the required parts according to user needs:
Inspection item self-table
Inspection item H
Appearance inspection
Basic error
Rise and fall variation
Deviation from zero compensationbzxZ.net
Position influence
Power number influence
Insulation resistance test
Dielectric strength test
Indicates inspection:
First inspection||t 6.3.1.2 For instruments with accuracy levels less than and equal to, which can be read multiple times, and which are to be subsequently verified, repair shop verified, periodic verified, and in-use inspected, each inspection point shall be read twice, and the same shall also be true for the other instruments. 6.3.1.3 For instruments with a common scale, only the scale line with numbers within the measuring range of one of the scales (called the gold inspection range) shall be read twice. The calibration is carried out, while for the remaining ranges (called the calibration range), only the range limit and the scale line that can determine the maximum error are checked.
6.3.1.4 For AC/DC dual-purpose instruments with a rated frequency of 50Hz, in addition to calibrating the scale lines with numbers within the measuring range under DC, the range limit and the scale line that can determine the maximum error should also be calibrated at the rated frequency of 50Hz.
6.3.1.5 For AC/DC dual-purpose instruments with a rated frequency range and an extended frequency range, the range limit and the scale line that can determine the maximum error should also be calibrated at the upper frequency of the rated frequency range and the upper limit of the extended frequency. 6.3.1.6 For AC instruments with a rated frequency range, they should be calibrated at the rated frequency. 6.3.1.7 For AC instruments with a rated frequency range and an extended frequency range, the scale lines with numbers within the measuring range of the instrument should not be calibrated at a frequency of 50Hz. Calibration, and for the extended frequency range, the upper limit frequency and the lower limit frequency (only for built-in five sensors), the upper limit of the range and the graduation line that can determine the maximum error must be calibrated separately. 6.3.1.8 It is stipulated that instruments that are calibrated with fixed-value wires or special wires with a certain resistance value should be calibrated together with fixed-value wires or special wires. 6.3.1.9 Instruments with external special shunts and additional resistors can be calibrated according to the calibration method of multi-range instruments. 6.3.1.10 When calibrating instruments with "fixed-value shunts" and "fixed-value additional resistors", the instrument and accessories should be inspected separately, and the instrument should not exceed the maximum allowable error. 6.3.1.11 Parallax should be avoided when reading
JJG124—2005
For instruments with hall-type pointers, the line of sight should be perpendicular to the instrument dial through the tip of the indicator. For instruments with mirror scales, the line of sight should be perpendicular to the mirror reflection image through the tip of the indicator. Overlap. 6.3.1.12 The instrument should be placed in the calibration environment for sufficient time (usually 2 hours) to eliminate the influence of temperature gradient. No preheating is required unless otherwise specified by the manufacturer. 6.3.1.13 When calibrating the resistance, use the mechanical zero adjuster and the electrical zero adjuster to adjust the indicator to the zero scale line before reading:
6.3.1.14 Under the conditions of 6.1.2, verification methods other than those in this regulation are also allowed: 6.3.2 Appearance inspection
The instrument should comply with the provisions of 5.1:
6.3.3 Basic error verification
6.3.3.1 Verification method using digital meters as the standard This method is applicable to the verification of DC and AC meters of all levels. Digital meters and matching equipment should comply with the requirements of Section 5
The digital meter should be preheated and calibrated according to the instructions for use, and the appropriate function and program should be selected. When the digital meter is used as an AC standard, there must be a test result of a frequency of 50Hs: Table 5 Requirements for digital meters and matching equipment
Accuracy level of the meter being tested
Upper limit of the measurement of the meter being tested
Actual error of the digital meter
Accuracy level of the standard resistor
Accuracy level of the voltage divider box
Ratio of the input impedance of the digital meter
to the impedance of the circuit being tested
Digital The error caused by the drop in the zero current of the voltmeter in the measuring circuit is a) Verification of the ammeter 1) When the ammeter is verified by a digital ammeter, the circuit wiring is as shown in Figure (a): current source and regulator Digital ammeter Current source and regulator Figure 1 Wiring diagram for verifying the ammeter with a digital meter 0.5
Digital Huawu
Voltmeter
JJG 124--2005
The actual value of the current being tested is 1, calculated according to formula (3): Where: 1, — the reading value of the digital ammeter, A. a=
2) When using a digital voltmeter to calibrate the ammeter, connect the circuit as shown in Figure "(b). Use a digital voltmeter to measure the voltage on the standard resistor to determine the current value. At the same time, it should be considered that the power consumption on the standard resistor (the frequency range should also be considered when using AC standard resistors) should not exceed the allowable value. The standard resistor can be selected according to Table 6. The actual value of the current to be tested is 1. (A). Calculate according to formula (4): t
Where: .—-the reading value of the digital voltmeter, V: R—the resistance value of the standard resistor,
3) Ammeter calibration procedure
First adjust the zero position of the meter to be tested, and then connect the measuring circuit to adjust the current source and slowly increase the current. Make the indicator of the ammeter to be tested sequentially indicate on each digital scale line, and record the actual value of this purple point. Increase the current to the working limit of the range or
scale line, and record the actual value of these points! The upper limit of the measurement of the tested ammeter
30 ~15
15 ~10
0.01 ~ 0.001
0.001-0.001
0.10001 - 0.00001
0.10001~0.0X001
decreases slowly in a moment, and the indicator sequentially points to the network resources with each number
Selection of standard resistor
Positive value of standard resistor (2)
Maximum power 1W
1000X)
Note: The standard resistor below 0 must be placed in transformer oil when used. b) Verification of voltmeter
1) The voltmeter to be verified is connected as shown in Figure 2: The actual value of the voltage to be tested is calculated according to formula (5): Maximum power 3W
Voltage source
and regulator
JJG 124—2005
Digital
Voltmeter
Figure 2 Wiring diagram for calibrating voltmeter with digital meter Un= UN
2) Verification procedure of voltmeter
First adjust the zero position of the meter to be tested, and then connect it to the measurement circuit: Adjust the voltage source and slowly increase the voltage so that the indicator of the voltmeter to be tested indicates on each digital scale line in sequence, and record the actual values of these points. Increase the voltage to above the upper limit of the range, and slowly decrease it so that the indicator indicates on each digital scale line in sequence, and record the actual values of these points. c) Verification of power meter
1) Use digital power meter to verify the power meter, and connect the circuit as shown in Figure 3 (a). CA
Voltage source
and regulator
Current source
and regulator
Figure 3 Wiring diagram for verifying power meter with digital meter The actual value of the power to be tested P is calculated according to formula (6): P,=Pr
Formula: t
-the reading value of the digital power meter, W.
Voltmeter
Digital
Voltmeter
2) Use digital voltmeter to verify DC power meter, and connect the circuit as shown in Figure 3 (b). When the fixed voltage method is used to verify the power meter, the stability of the fixed voltage instrument is required to be no greater than 1/10 of the maximum allowable error of the meter to be tested, and the actual value of the power to be tested P. (W), calculated according to formula (7): Ua.Us
Po= I,- Uat =R
Where: U,
The voltage across the standard resistor: V;
The reading of the standard voltmeter, V.
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