ABB DCS880 series, Руководство по обслуживанию

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105
Service
3ADW000488R0101 DCS880 Service manual e a
Exchange current transformers size H7
Before the work is started, disconnect the converter completely from the power supply,
then check the voltage free condition and make sure, everything is located in an electrical
and mechanical safe condition!
If current transformers fail or need to be repaired, the following has to be considered:
− It is important, that all current transformers are orientated and mounted in the same way on the busbars.
− Check the wiring of the old current transformers according the figure in chapter Wiring . It is important, that
all current transformers are wired in the same way. Take additional care in case the connection is not
done by coded twisted pair cables.
Current transformer type
− The current transformers are located in the H7 module.
− AC busbars are routed through the current transformers. The current transformers are kept in place by
design and need no further mounting.
− The connection to the electronics is done via twisted pair cables with coded faston plugs on both ends.
Exchange
− Remove the fuses connected to the
busbars leading to the current
transformers.
− To get access to the current transformers
remove the bolts with sleeves from the
AC busbars outside the converter.
− Make sure the current transformers are
not falling down when removing the bolts
and sleeves.
− Install the new current transformers with
proper orientation. No extra mechanical
mounting is necessary.
− Fasten the bolts including sleeves.
− Take care of proper electrical
connections.
−
Remount the fuses.