7.6.3 Replacing

Collector- Emitter junctions of the transistors are connected to the power connector of the module Values that could be measured with an ohmmeter from backside of module power connections: Collector- Emitter: positive (red) test lead of ohmmeter in Collector - resistance shall be “infinite”.

Emitter- Collector: positive (red) test lead of ohmmeter in Emitter – resistance shall be “zero” ( less than 1mΩ) because of anti-parallel diode.

Measurements shall be done for all 4 transistors in case of double module (SIBAC BB SD-1500WL) and all 6 transistors in case of triple module (SIBAC BB ST1500WL).

Transistor #1 : collector connected in P and emitter in L1 Transistor #2 : collector connected in L1 and emitter in N Transistor #3 : collector connected in P and emitter in L2 Transistor #4 : collector connected in L2 and emitter in N Transistor #5: collector connected in P and emitter in L3 Transistor #6: Collector connected in L3 and emitter in N If the measured values of resistance are different than above, then the module is defective and needs to be replaced.

7.6.3 Replacing

• A31, A41, A51 modules are of this type.

Removing modules

• All power connections are of busbars type and control connections are of plug connector type. All IGBT modules are pluged in on DC link low inductive busbar and the output connections are done with power cables as shown in the photo below.

Power connections

Control connections

Coolant pipe

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• Remove power cables of respective IGBT modules as follows A31: 10901, 10902, 10903 A41: 10804, 10805, 10806 (only in HD) A51: 10801, 10802, 10803 Using 18 no bit and torque wrench and aside the power cables Remove Connectors from Module as follows: A31: A31-A40-X2, A31-A50-X2, A31-A40-X1, A31-A50-X1 A41: A41-A40-X2, A41-A50-X2, A41-A40-X1, A41-A50-X1 (only in HD) A51: A51-A40-X2, A51-A50-X2, A51-A40-X1, A51-A50-X1

• Remove connectors from positions X1, X2, X3 as shown in figure • Remove input output coolant pipes from module. • Remove locking bracket from front by removing M8 screw, plain washer & spring washer with bit no 13 & torque wrench • Loose the screws of IGBT module from inside by using extension tool (no. 101584869) • Take IGBT module out from the panel.

CAUTION

• Weight of the IGBT module is 43 kg approximately. • Antifrogen N that has been used has a corrosive effect. Further, Antifrogen N that has leaked can cause short-circuits. This is the reason that each time the cooling water connections are opened, the phase module and especially the modules located below it, must be carefully cleaned and any Antifrogen N that has leaked must be removed.

Installing modules

• Mount IGBT module into the panel on FRP Guide rail • Tight the screws in the panel by using extension tool 101584869 & torque wrench. Torque 10 Nm. • Mount power cables of respective IGBT modules as follows. A31: 10901, 10902, 10903 A41: 10804, 10805, 10806 (only in HD) A51: 10801, 10802, 10803

• By screwing hex screw M12X30, HT spring washer and plain washer (pos. no. 110, 111, 125) Using 18 no. bit and torque wrench and apply torque of 50 Nm • Mount connector of respective IGBT module as follows: A31: A31-A40-X2, A31-A50-X2, A31-A40-X1, A31-A50-X1 A41: A41-A40-X2, A41-A50-X2, A41-A40-X1, A41-A50-X1 (only in HD) A51: A51-A40-X2, A51-A50-X2, A51-A40-X1, A51-A50-X1

• Mount respective coolant input output pipes • Mount locking bracket at front by M8 screw, plain washer & spring washer with bit no 13 & torque wrench Torque 25 Nm

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