Rockwell Automation SA3000 High Power Modules - Manual (Page 33)

Diagnostics and Troubleshooting 4-1
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Diagnostics and Troubleshooting
This chapter describes the equipment needed to check the operation of the Power
Module and the tests to be performed. Included are descriptions of the Power Module
faults and warnings monitored by the Distributed Power System software. Procedures
are also provided for replacing Power Module cabinets, sub-assemblies, and fuses.
4.1 Required Test Equipment
The following equipment is required when servicing the SA3000 Power Module:
• an oscilloscope with an impedance of at least 8 megohms
• a 10:1 probe
• an isolated voltmeter (1000V DC)
• a clamp-on ammeter (1500A)
Note that all measuring devices-meters-oscilloscopes that are AC line-powered must
be connected to the AC line through an ungrounded isolation transformer.
!
ATTENTION: DC bus capacitors retain hazardous voltages after input
power has been disconnected. After disconnecting input power, wait ten
(10) minutes for the DC bus capacitors to discharge. Open the cabinet
doors and check the voltage across the DC bus bars, 347 A,B,C (+ bus)
and 345 A,B,C (- bus), with an external voltmeter to ensure the DC bus
capacitors are discharged before touching any internal components.
Failure to observe this precaution could result in severe bodily injury or
loss of life.
ATTENTION: The SA3000 Power Module contains printed circuit boards
that are static sensitive. Do not touch the boards’ components,
connectors, or leads. Failure to observe this precaution could result in
damage to, or destruction of, the equipment.
!
ATTENTION: The Power Module is not isolated from earth ground. AC
line powered test instruments used to measure Power Module signals
must be isolated from ground through an isolation transformer. This is
not necessary for battery-powered test instruments. Failure to observe
this precaution could result in bodily injury.
ATTENTION: If a megohmmeter (megger) is used to verify an
inadvertent ground internal to the motor, make certain that all leads are
disconnected between the rotating equipment and the Power Module
cabinet. This will prevent damage to electronic circuitry (Power Modules
and their associated circuitry) due to the high voltage generated by the
megger. Failure to observe this precaution could result in damage to or
destruction of the equipment.