Chapter 5 - Exchange of Thyristors for Size A5
DCS 500 / DCS 600 Service Manual
VI A
5 - 5
7.
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.
8.
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 5-3). Do not tighten the screws any fur-
ther.
Note
: The correct torque is indicated by means of the welded
indicating spring.
9.
Perform an OHM test to make sure the thyristor is ok.
10.
Reconnect the DC – busbars, branch fuses and all other dis-
mantled parts.
11.
Perform an OHM test between U1, V1, W1 and C1, D1 to make
sure the power part is ok.
U1
V1
W1
V24
V11
V13
V26
V22
V15
V14
V21
V23
V16
V12
V25
left stack
rear
front
right stack
front
rear
View from the left
Front view
View from the right
Figure 5-4
Location of thyristors in frame A5 (4-Q bridge)
3ADW000093R0601_DCS500B/DCS600_Service Manual_e_f