ABB ACH550-02-645A-4 [395/454] Capacitors

Diagnostics and maintenance 391

ACH550-02 User's Manual

Capacitors

Reforming

The drive DC link capacitors need to be reformed (re-aged) if the

drive has been non-operational for more than one year. Without

reforming, capacitors may be damaged when the drive starts to

operate. It is therefore recommended to reform the capacitors

once a year. See page 19 for how to check the date of

manufacture from the serial number shown on the drive labels.

For information on reforming the capacitors, refer to Guide for

Capacitor Reforming in ACS50, ACS55, ACS150, ACS310,

ACS350, ACS355, ACS550 and ACH550 (3AFE68735190

[English]), available on the Internet (go to www.abb.com and

enter the code in the Search field).

Replacement

The drive intermediate circuit employs several electrolytic

capacitors. Their lifespan is at least 90,000 hours depending on

the operating time of the drive, loading and ambient

temperature. Capacitor life can be prolonged by lowering the

ambient temperature.

It is not possible to predict a capacitor failure. A capacitor failure

is usually followed by an input power fuse failure or a fault trip.

Contact ABB if a capacitor failure is suspected (see page 421).

Replacements are available from ABB. Do not use other than

ABB specified spare parts.