Rockwell Automation MV SMC Flex Motor Controller (for Series K or later) - Manual (Page 149)

Rockwell Automation Publication 1560E-UM051F-EN-P - June 2013 139
Troubleshooting Chapter 9
Measure across R2, R4, R6, R10, R12, R14, R18, R20 and R22 located at
the bottom of each leg of the module. The resistance should be 11.3 kohm.
(The two ground connections must be connected to ground, or to each
other if the module has been removed.)
If the values for each leg vary by more than 1%, the voltage sensing module
may need to be replaced. See
Table 35 on page 199 in Appendix G ., and
refer to procedure on page 120 .
The ribbon cable must be connected to J1 only on the voltage sensing
board or the equipment will not function.
4. When repairs are complete, re-assemble all parts, check all fasteners, and
verify all connections are correct and tight. Make sure all barriers and
mechanical parts are in place and secured.
5. Repeat Thyristor (SCR) resistance checks ( page 123 ) and Power Supply
Tests ( page 64 ).
Snubber Resistor
Replacement When replacing the ceramic wire-wound type snubber resistors, use caution
when handling the parts. The resistor element is under a thin coating on the
ceramic tube, and it may be damaged if dropped, struck or scraped.
ATTENTION: Grounds must be reconnected on the voltage sensing
boards. Failure to do so may result in injury, death or damage to
equipment.
TIP The white high voltage wires must be connected to the correct tap on
each leg of the voltage sensing module. Failure to do so may result in
equipment damage.
ATTENTION: Make sure ground wires from the Voltage Sensing Module
are securely connected to the ground bar in the low voltage panel or
ground bus. Failure to do so may result in severe injury or equipment
damage.