Thermal Dynamics CUTSKILL C-35C Service Manual page 28

Testing of diode modules requires a digital volt/ohmmeter that has a diode test scale. Remember that even if the
diode module checks good, it may still be bad. If in doubt, replace the diode module.
1. Remove AC power. Refer to Appendix 3 Wiring diagram.
2. Locate the IGBT diode module to be tested.
3. Remove P5 from IGBT module.
4. Set digital volt/ohmmeter to diode test scale.
5. Connect the volt/ohmmeter positive lead to the anode (+) of the diode and the negative lead to the cathode (-) of
the diode for forward bias testing (refer to following figure). A properly functioning diode will conduct in the
forward bias direction and indicate between 0.3 to 0.9 volts.
TROUBLE SHOOTING
Forward Bias
Diode Conducting
Diode Test Symbol
Anode
Cathode
Testing Diode Forward Bias
6-6
Art # A-00307
0.75
VR COM A
_
+
Manual 0-4745