Specifications

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SECTION 5 MACHINE TESTING / TROUBLESHOOTING / SERVICE
5.6 Output Rectier 1 (952150)
The Bridge diode D1 is a full wave bridge rectier, which converts the IGBT’s 290 VAC output to dc volts
which is supplied to the shunt and output inductor (L1). Due to the tolerance of the inputs, the range of
values for this dc voltage is from 260Vdc to 290Vdc. The resistors in the circuit, R3 through R6, as well as
capacitors C5 through C8 are used for electrical noise suppression.
Testing:
With the unit shut down, disconnect the diode from the circuit and test it with an Ohmmeter in the
diode scale. Be mindful that the middle ac input post is not connected on the output bridge. Viewing the
diode with the positive / negative terminals to the left, the 3 ac input terminals are number 1 through 3
from top to bottom although this is not denoted on the diode itself.
To test, perform the following diode voltage checks:
Output Bridge Diode Voltage Checks
Probe (+) Probe (-) Value (V)
- 3 0.3
1 + 0.3
Post #2 is not connected
CONTENTS