IEC 60051-9-2019 pdf free.Direct acting indicating analogue electrical measuring instruments and their accessories-Part 9: Recommended test methods.
4.1General
Test equipment shall have sufficient accuracy and stability for the determination of theintrinsic uncertainty of an instrument and the variations.
NOTE Calibration protocols can be used.
4.2Test equipment for measuring the intrinsic uncertainty of an instrument and the variations
The maximum instrumental uncertainty of reference instruments used to determine theintrinsic uncertainty of an instrument and the variations shall be 0,2 times the class index ofthe instrument under test. In the event that a calibration protocol is used, the maximumcalibration uncertainty shall be 0,2 times the class index of the equipment under test(EUT).
4.3Test equipment for overload tests,self-heating, damping, overshoot and response time
The maximum uncertainty of the settings of the electrical quantities that will be used to testoverload, self-heating, damping, overshoot and response time shall be ±1 % of those settings.
4.4Test equipment for phase shift
Test equipment for settings of the phase shift of power meters with class indexes of 0,5 orhigher shall have an uncertainty of 1 ° or better.
Test equipment for settings of the phase shift of power meters with class indexes below 0,5shall have a maximum uncertainty of 10,1° or better. The instrumental uncertainty of testequipment for phase meters and power factor meters shall comply with 4.2.
4.5Test equipment for temperatures
Equipment for the setting of temperatures shall have a maximum uncertainty in thetemperature setting of ±1 °C in the case of EUT with a class index equal to or below 0,3. Inthe case of EUT with a class index above 0,3, the maximum uncertainty of the setting shall be土2°C.
4.6Test equipment for humidity
Equipment for settings of humidity shall have a maximum uncertainty in the humidity settingsof +3 %
5 Test methods for determination of intrinsic uncertainty
The intrinsic uncertainty at defined test points shall be checked with slowly increasing anddecreasing measuring values without any overshoot and without tapping. The test points forthe type test can be defined by the manufacturer. During the routine tests,tests should becarried out at full scale at all ranges and the characteristics should be tested in one range at aminimum.IEC 60051-9 pdf download.