(1) Megger generally have several, 500, 1000, 2500, 5000 v shall be chosen according to equipment voltage grade according to which a megohmmeter.
(2) Of the insulation resistance measuring 12 Volt Motor With Gearbox equipment, must cut off power supply first, with larger capacitance devices (such as capacitors, transformers, motors and cable line), you must first to discharge.
(3) Should be put in horizontal position by megger, before his connection to shake megohmmeter, see whether the pointer in the "up", then "L" and "E" two terminal sub, slowly shaking megohmmeter, watching to see if the pointer refers to the "zero", in type semiconductor megohmmeter short-circuit calibration should not be used.
(4) Megger cable soft line, the use of more shares and should have good insulation.
(5) Overhead line and connected with the overhead High Torque 12v Dc Motor line of electrical equipment, in the event of a thunderstorm, or not all the power of double overhead line and bus, in the circuit of the induction voltage being measured more than 12 v, the measurement is prohibited.
(6) Measurement, cable, large capacity transformer and capacitor motor, it is certain to should have the charging time. The more the greater the capacitance, charging time should be long. In general will be subject to rotation by megger readings in a minute.
(7) When the wave measuring insulation resistance, Vending Machine Motor should keep megohmmeter rated speed, the average is 120 RPM. Analyte when a large capacitance, in order to avoid the pointer swing, can be appropriately increase the speed (such as 130 r/min).
Analyte (8) surface should be wiped clean, must not have dirt, so as to avoid leakage affect measurement accuracy.
(9) Megger did not stop running and equipment before discharge, do not touch the measurement part and megohmmeter with the hand terminal, so as to avoid electric shock.
Measured with a megger insulation, general provisions shake test readings shall prevail in a minute. Because after the insulator with dc voltage, (current) absorption current through the insulator will gradually decreases with the increase of over time. And insulation of dc resistivity is determined based on the steady state conduction current, and insulator its insulation materials with different absorption current decay time is different, but the experiment proved that the vast majority of insulating material absorption current has stabilized after a minute, so provisions to pressure a minute insulation resistance value to determine the insulation performance is good or bad.
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