Chapter 7 - Exchange of Thyristors for Size C4
VI A
7 - 4
DCS 500 / DCS 600 Service Manual
TORQUE INDICATING SPRING
Loose
condition
Correct torque
In
-
s
u
la
ti
n
g
tu
b
e
Insulating plate
Heatsink
Figure 7-2
Aluminium spring with welded indicating spring
-
Tighten the nuts of the mounting clamp by hand so that the
clamp is in parallel with the contact surface of the heat sinks.
Note:
The indicating spring is a very sensitive instrument and
must be handled with care.
-
Tighten each nut in turn, half a turn at a time with the help of a
ring spanner until the indicating spring clicks into position “cor-
rect torque” (see
Figure 7-2). Do not tighten the screws any
further.
Note:
The correct torque is indicated by means of the welded in-
dicating spring.
-
Perform an OHM test to make sure the thyristor is ok.
-
Reconnect the DC / AC – busbars, branch fuses and all other
dismantled parts.
-
Perform an OHM test between U1, V1, W1 and C1, D1 to make
sure the power part is ok.
3ADW000093R0601_DCS500B/DCS600_Service Manual_e_f
