Agilent Technologies U1251A User's Manual And Service Manual page 147

11 The current can be measuring from 2.5 A to 10 A continuous, and the additional of 0.5% to specified accuracy as measure
the signal greater than 10 A~20 A for 30 seconds maximum. After measured current for > 10 A, to cool down the meter for
2 times of measuring time you applied before low current measurement.
12 For signal frequency greater than 1 kHz, additional 0.1% per kHz to be added to accuracy.
13 Ensure that the ambient temperature is stable within ± 1ºC. Make sure that the multimeter is placed in a controlled
environment for at least 1 hour. Keep the multimeter away from any ventilation exit. Do not touch the thermocouple test
lead after connecting it to the calibrator. Allow the connection to stabilize for at least another 15 minutes before performing
the measurement.
Agilent U1251A/U1252A User's and Service Guide
Performance Tests and Calibration 7
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