ABB ACH480, Hardware Manual

Page: 21 / 214

Before installation, start-up and maintenance work on the drive:
• Stop the drive.
• Disconnect the motor from the drive with a safety switch or by other means.
• If you cannot disconnect the motor, make sure that the motor cannot rotate during
work. Make sure that no other system, like hydraulic crawling drives, can rotate the
motor directly or through any mechanical connection like felt, nip, rope, etc.
• Do the steps in section Electrical safety precautions (page 17) .
• Measure that the installation is de-energized.
• Use a multimeter with an impedance greater than 1 Mohm.
• Make sure that the voltage between the drive input power terminals (L1, L2, L3)
and the grounding (PE) busbar is close to 0 V.
• Make sure that the voltage between the drive output terminals (T1/U, T2/V,
T3/W) and the grounding (PE) busbar is close to 0 V.
• Make sure that the voltage between the drive DC terminals (R+/UDC+ and
UDC-) and the grounding terminal (PE) is close to 0 V.
• Install temporary grounding to the drive output terminals (T1/U, T2/V, T3/W). Connect
the output terminals together as well as to the PE.
During the start up:
• Make sure that the motor cannot run overspeed, for example, driven by the load.
Motor overspeed causes overvoltage that can damage or destroy the capacitors in
the intermediate circuit of the drive.
￭ Safety in operation
WARNING!
Make sure that the motor cannot run overspeed, for example, driven by the load.
Motor overspeed causes overvoltage that can damage or destroy the capacitors
in the intermediate circuit of the drive.
Safety instructions 21