Remove Faulty Thyristor - ABB DCS 500 Series Service Manual

Remove faulty thyris-
tor
DCS 500 / DCS 600 Service Manual
1. Remove the screws of the DC – busbars and branch fuses pre-
venting the stack to be prized open.
Note: It depends on the location of the defective thyristor which
DC – busbar and fuses have to be disconnected.
2. Write down the direction and location of the thyristors to be re-
moved and mark their gate leads.
3. Remove the gate leads if possible.
4. Loosen the mounting clamp (see figure 5-3 ) at the top of the
thyristor stack.
Attention: While loosen the mounting clamp the indicating spring
must be pulled out a little, otherwise the spring will be damaged!
5. Attach the disassembly tool at the faulty thyristor and prize open
the upper and lower heat sinks (see figure 5-2 ).
6. Remove the thyristors.
Attention: To centre the thyristors spring pins are used. The pins
are inlayed into all lower heat sinks. Open the gap wide enough that
the thyristor and the pins are not damaged while removing the thy-
ristor!
View from
the right
Figure 5-2 How to use the disassembly tool
3ADW000093R0601_DCS500B/DCS600_Service Manual_e_f
Chapter 5 - Exchange of Thyristors for Size A5
Mounting clamp
Disassembly tool
Front view
View from
the left
VI A 5 - 3