Electronic Load Meter Metrological Calibration

Standardize the calibration conditions of DC electronic load meters

(including environmental conditions and conditions for selecting standard instruments), calibration items, methods, processing of calibration results, and calibration cycles to ensure the accuracy of their measurements.

02 Scope of Application

2.1 All DC electronic load meters used in our factory are applicable

2.2 This standard is only applicable to the internal calibration of our factory's DC electronic load instrument

03 Environmental conditions for calibration

3.1 Environmental temperature: 20 ± 10 ℃

3.2 Relative humidity: ≤ 80%

3.3 Avoid strong electric and magnetic field interference

04

Calibration equipment (standard instruments and auxiliary equipment)

4.1 Requirements for standard equipment (standard instruments)

4.1.1 The standard instruments used for calibration must be calibrated by a metrological calibration institution approved and authorized by CNAS, and must be within the validity period

4.1.2 The measurement range of the standard used for calibration should cover the measurement range of the calibrated instrument

4.1.3 The uncertainty of the standard used for calibration should be better than one-third of the uncertainty of the calibrated instrument

4.1.4 The sensitivity (accuracy) of the standard used for calibration should be 1/5-1/10 of the allowable error of the calibrated instrument

4.2 Main standard instruments and auxiliary equipment for calibration

4.2.1 Calibration standard equipment: digital display multimeter

4.2.2 Calibration auxiliary equipment: DC stabilized power supply

05 Calibration items and methods

5.1 Calibration items

5.1.1 External inspection 5.1.2 Normal operation inspection

5.1.3 Error verification of DC voltage and DC current

5.2 Verification Method

5.2.1 Appearance inspection: The appearance of the calibrated DC electronic load instrument should be intact, without mechanical damage that affects normal operation

5.2.2 Normal operation check: Connect the power supply to ensure that the calibrated DC electronic load instrument is in working condition. Check whether the display screen displays normally and whether each button is sensitive or ineffective.

5.2.3 Error verification of DC voltage and DC current.

5.2.3.1 DC voltage error verification: First, turn on the power switch of all instruments and connect them according to the instrument connection diagram shown in Figure A, Set the multimeter to the DC voltage measurement position, set the DC stabilized power supply to a fixed voltage value, read the readings of each instrument, use the voltage measured by the multimeter as the standard value Uo, and use the voltage measured by the calibrated DC electronic load instrument as the measurement value U. Set several sets of different voltage values according to the above method for verification, and calculate the DC voltage measurement error according to formula ①. △ U=(U Uo)/Uo × 100% Formula

Voltage Error Verification

① Figure A DC Voltage Error Verification Instrument Connection Figure 5.2.3.2 DC Current Error Verification: First, turn on the DC stabilized power supply, adjust the voltage to around 2-5V, adjust the multimeter to the DC current measurement gear, and adjust the verified DC electronic load meter to CC mode. Connect the instrument according to the instrument connection diagram shown in Figure B, Then set the DC electronic load to a fixed current value, read the current display value of the standard digital multimeter and use it as the standard value Io. Use the display value of the DC electronic load instrument as the set value I. Set several different current values of the DC electronic load according to the above method for verification, and calculate the current display error according to formula ②. △ I=(I-Io)/Io × 100% Formula ② Figure B DC Current Error Calibration Instrument Connection Diagram

Current Error Calibration

5.2.3.3 According to the allowable deviation △ U ≤ ± 2%& △ I ≤ ± 2%, determine whether the verified DC electronic load instrument is qualified.

5.2.3.2 DC current error verification:

First, turn on the DC stabilized power supply, adjust the voltage to around 2-5V, adjust the multimeter to the DC current measurement gear, and adjust the verified DC electronic load instrument to CC mode. Connect the instrument according to the instrument connection diagram shown in Figure B, and then set the DC electronic load to a fixed current value, Read the current reading value of the standard digital multimeter and use it as the standard value Io. Use the reading value of the DC electronic load meter as the set value I. Set several different current values of the DC electronic load according to the above method for verification, and calculate the current reading error according to formula ②. △ I=(I-Io)/Io × 100% formula ② Figure B DC current error calibration instrument connection diagram

06 Processing of calibration results and calibration cycle

6.1 Processing of calibration results

6.1.1 DC electronic load meters that have passed calibration must provide a calibration report/record, And attach a calibration label

6.1.2 DC electronic load meters that have been partially verified as qualified (the indication error of a single item or detection point exceeds the allowable range) must provide a calibration report/record, print out the calibration data of the unqualified item or/and detection point, and attach it in a prominent position on the instrument (for reference by the instrument user), and attach the calibration label

6.1.3 For DC electronic load meters that have been verified to be completely unqualified, no calibration report/record needs to be issued. However, the equipment should be labeled as suspended for use, and the user unit should be notified to send for repair. After the repair is OK, the calibration can be conducted again

6.2 Calibration Cycle The DC electronic load instrument should undergo periodic calibration, and its calibration cycle should generally not exceed one year. In special circumstances, appropriate shortening or extension can also be made

BAIJIAN Platform Service Quality Commitment

Conduct Fairness: Consciously abide by the fairness statement.

Method Science: Follow the principle of seeking truth from science and strictly follow the prescribed methods to carry out calibration work

Result: The certificate specification is rigorous and the data is reliable

Work: Based on the actual situation and customer needs, continuously improve the business process to ensure that the calibration work is completed within the promised time.

Reasonable charging: The calibration fee shall not exceed the charging standards approved by the national, provincial, and municipal price departments, and shall not be higher than the average level of peers.

Customer satisfaction: Proactively understanding customer needs, providing services, timely accepting and handling customer complaints, providing fast and convenient follow-up services

BAIJIAN is a professional third-party instrument calibration and testing agency with various instrument calibration and testing needs and details. Free consultation agency online consultant: 400-101-7153, doing testing on BAIJIAN  Www.baijingtest. org. cn &Nbsp- The issuance of authoritative testing reports has legal effect