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Exchange thyristors size H4T
3ADW000803R0101 DCS880 H4T (Tosa) manual en a
Install new thyristor modules
1.
Ensure that the new thyristor module is of the correct type.
2.
Remove old heat-conducting compound (grease) from the heat sink. Clean the mounting surfaces
(heat sink and thyristor module) with an appropriate solvent (e.g. ethanol) by means of tissue paper.
When the heat sink is clean, spread out the heat-conducting compound with a rubber spatula or by
hand.
3.
Apply a
thin
layer of heat-conducting
compound to the new thyristor module.
4.
Spread the heat-conducting compound evenly by moving the thyristor module forward and
backward on the heat sink.
5.
Tighten all clamping screws by hand until the screw heads touch the bottom of the thyristor module.
Then pre-torque the screws to 2.0 Nm.
Note:
If the thyristor module is mounted by means of four screws, tighten the screws crosswise.
6.
Tighten the screws to nominal torque according to table Nominal mounting torque for thyristor
modules.
Thyristor modules
Nominal mounting torque
Size (width)
Type
Electrical connections
Thyristor module to heat sink
60 mm block
MT3
10.8 … 13.2 Nm
5.1 … 6.9 Nm
7.
Reinstall the current transformer. Make sure, its position and direction is correct.
8.
Reinstall the busbars. Make sure, the correct torque is applied according to table above.
9.
Reconnect all gate leads to the thyristor module.
10.
Perform an OHM test to make sure the thyristor is ok.
11.
Reconnect all cables and plugs at the SDCS-PIN-H51:
−
X1E ground.
−
XC1 and XD1 DC voltage measurement.
−
XU1, XV1, XW1 mains voltage measurement.
−
X22 temperature sensor.
12.
12. Reconnect all cables and plugs at the SDCS-PIN-H41:
−
X1G … X6G gate leads.
−
X1 ground.
13.
Reinstall the card holder containing the SDCS-PIN-H41 and the SDCS-PIN-H51.
14.
Reinstall the metal sheet containing the power supply.
15.
At the SDCS-CON-H01 reconnect the flat cables (XC12, XS13), the cable connected at X38 and re-
hinge the electronic unit.
16.
Reconnect the grounding/holding screws at the electronic unit.
17.
Reconnect all I/O plugs at the electronic unit and all connections at the present plug in options.
18.
Reinstall the design cover and the control panel.
