ABB ACS 600 MultiDrive, Safety And Product Information

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Safety Instructions
4 ACS 600 MultiDrive
Starting TSU or DSU Note the warning below before starting drives equipped with a Thyristor
or Diode Supply Section.
WARNING! Before power switch-on, make sure that a sufficient
inverter power is connected to the intermediate circuit. Rules of thumb:
1. The sum power of the inverters connected must be at least 30% of
the sum power of all inverters.
2. The sum power of the inverters connected must be at least 30% of
the rated power of the braking section ( P
br.max
) if present.
If the above mentioned rules are not followed, the DC fuses of the
connected inverter(s) may blow or the braking chopper (if used) may
be damaged.
The phenomena which result in a fuse blow are as follows:
• At start, a charging current high enough for charging all the
inverters flows to the connected ones.
• In Thyristor Supply Sections, the DC voltage may overshoot the
controller bridge change limit, causing an immediate change to
regeneration and a high reverse current.
• The DC voltage may overshoot the braking chopper controller
voltage limit, causing an immediate switching into braking mode
and a high braking current, which in turn discharges low power
inverter capacitors.
The braking chopper may be damaged by repeated on-off switching of
the braking due to a high supply and braking section power compared
to the inverter power.