Siemens Eupec, Manual

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Physical Description MicroHarmony Cell Sizes 40 - 260A Manual
2-14 19001467: Version 1.0
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2.10.2 Semiconductor Torque Specifications
Proper heat sink mounting connections are just as important as proper thermal compound application. An insufficient
tightening torque may cause the contact thermal resistance at the base plate to increase or the screws to come loose
during shipping or operation. Excessive tightening torque may damage the IGBT's plastic case. The ordering of bolt
tightening is also important to ensure a uniform thermal bond to the heat sink. Likewise, proper electrical terminal
torque is required. Insufficient tightening torque may increase contact resistance and localized heating or the screws
may come loose. Too much torque can crack the case or damage the internal bond wires. The assembly drawing
identifies the proper application procedure, which is shown below for the 40-140A cells:
Figure 2-7: IGBT and Diode Mounting Instructions
Do not exceed 4Nm (2.95ft-lb)
mounting or terminal torque.
Do not exceed 5Nm (3.69 ft-lb)
mounting or terminal torque.