ABB DCS800 Service Manual page 33

How to remove the converter fans in a frame D3 (four fans)
Converters types DCS800-S01-0405-0x to DCS800-S02-0520-0x using four 115
VAC fans. Depending on the supply voltage they are either connected in series, for
230 VAC. or in parallel, for 115 VAC:
Fan configuration D3
In case a fan fails there are different approaches due to the incoming voltage.
230 VAC:
With a supply voltage of 230 VAC fans M55 and M56 are connected in series as
well as fans M57 and M58. Consequently fans connected in series have to be of
the same manufacturer and type. Thus it is not possible to change only the broken
fan. Always change the two fans connected in series.
115 VAC:
With a supply voltage of 115 VAC all fans are connected in parallel. Thus it is
possible to change only the broken fan.
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