1. Overview
The insulation resistance meter (megohmmeter) is a national mandatory calibration measuring instrument, and its calibration regulations are as follows. The main standards of the calibration device are high-voltage and high-resistance boxes and high-voltage voltmeters. The type insulation resistance meter calibration device integrates a high-voltage high-resistance box (high-resistance output part) and a high-voltage digital voltmeter (voltage input part) into one.
The upper limit of measurement of the resistance output part of the calibration device is, and the nominal operating voltage is. The device is designed with independent leakage shielding terminals and grounding terminals, and there is no obvious instability, short circuit or open circuit during the measurement process. Meet the requirements of the insulation resistance meter calibration regulations and the DC resistor calibration regulations. It can be used for the verification of various types of pointer insulation resistance meters.
The resistance output part of the calibration device uses a patented rolling high-voltage switch, which can still meet the requirements of calibration regulations after being used 10,000 times. It has a long technical life and mechanical life. The nominal measurement voltage of the voltage measurement part of the calibration device is, input impedance. This device can measure the open circuit voltage, median voltage and peak voltage of the megger.
2. Main technical parameters
. Resistance output (high voltage and high resistance box) part
. Accuracy level and working voltage (current) of the resistance output part
Resistance value
Accuracy level
Nominal voltage
Resistance
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Accuracy level
Nominal current
. Adjustment range~, Adjust the fineness to
. Use environmental conditions
Reference temperature range ~ ℃
Nominal use temperature range ~ ℃
Reference humidity range ~ %
Nominal use humidity range ~%
. Resistance variation limit variation caused by changes in a single influencing quantity under reference conditions
Type of influencing quantity
Nominal use range
Allowable variation
Ambient temperature
~℃
/ %
Relative humidity
%～%
&/ ＞&%
Operating voltage
(~/) Nominal voltage
&/ ＞&%
★ It is the accuracy level of the resistance disk of the resistance output part of the calibration device (the value of each resistance disk is different)
. In the insulation resistance calibration device The insulation resistance between the circuit of the resistor output part and any other external metal not electrically connected to the circuit shall not be less than the resistance value measured at the nominal voltage.
. The circuit between the resistance output part of the dielectric strength verification device and the reference ground point for testing should be able to withstand the actual sinusoidal AC voltage with a frequency of ~ and last for a long time without breakdown or arcing.
. The residual resistance at the output end of the resistance output part of the calibration device should be < its deterioration <.
. Dimensions
. Weight<
． Voltage measurement (high voltage DC digital voltmeter) part
. Measuring range~
. Accuracy (% reading digits)
. Power supply
. Input resistance
. Display four and a half digits, liquid crystal display
. The peak voltage measurement circuit meets the requirements of the figure in the insulation resistance meter verification regulations.
GZX92A insulation resistance meter calibration device