ABB DCT880, Service Manual

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9 years preventive maintenance
Following additional actions have to take place:
− Replace the power interface board SDCS-
PIN-H of units T1 … T5 (DCT880-W0x-
0020-0x … DCT880-W02-0960-0x).
The SDCS-PIN-H is located between the
heat sink and the electronic tray. It
operates continuously, because it supplies
the unit’s electronics even when the load
current is switched-off. Therefore, all its
components are exposed to hot
conditions.
Additionally the electrolytic capacitors on
the SDCS-PIN-H are aging. The SDCS-
PIN-H also is equipped with several
capacitors, which are sensitive to high
ambient temperature.
− Aging of the electronic card result in:
1. Damage other devices.
2. Trip the thyristor power controller and cause unexpected shutdown.
− Replace the flat cables of all units T1 … T5.
Environmental conditions, especially temperature and humidity could cause corrosion on the contact
surfaces and embitterment of the insulation.
− Aging of the flat cables result in:
1. Contact problems.
2. Flat cable insulation breaks.
Preventive Maintenance
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