ABB ACS880-34 Series - Measuring the insulation

Measuring the insulation
￭ Measuring the insulation of the drive
WARNING!
Do not do any voltage withstand or insulation resistance tests on any part of the
drive as testing can damage the drive. Every drive has been tested for insulation
between the main circuit and the chassis at the factory. Also, there are
voltage-limiting circuits inside the drive which cut down the testing voltage
automatically.
￭ Measuring the insulation of the input power cable
Before you connect the input power cable to the drive, measure its insulation according to
local regulations.
￭ Measuring the insulation of the motor and motor cable
WARNING!
Obey the safety instructions of the drive. If you ignore them, injury or death, or
damage to the equipment can occur.
If you are not a qualified electrical professional, do not do installation or
maintenance work.
1.
Do the steps in section Electrical safety precautions (page 18) before you start the work.
2. Make sure that the motor cable is disconnected from the drive output terminals.
3. Measure the insulation resistance between each phase conductor and the protective
earth conductor. Use a measuring voltage of 1000 V DC. The insulation resistance of
an ABB motor must be more than 100 Mohm (reference value at 25 °C [77 °F]). For the
insulation resistance of other motors, refer to the manufacturer’s instructions.
Note: Moisture inside the motor casing reduces the insulation resistance. If you think
that there is moisture in the motor, dry the motor and do the measurement again.
1000 V DC,
>
100 Mohm
U1-PE, V1-PE, W1-PE
M
3~
U1
V1
W1
PE
ohm
￭ Measuring the insulation of brake resistor and resistor cable
Obey the instructions given in section Measuring the insulation of the brake resistor
circuit (page 232).
94 Electrical installation