Visual Inspection - GE AF-650 GP Operating Instructions Manual

4.4 Visual Inspection

The table below lists a variety of conditions that require visual inspection as part of any initial troubleshooting procedure.
Inspect For
Auxiliary equipment
Cable routing
4
Control wiring
Drive cooling
Drive display
Drive interior
EMC considerations
Environmental conditions
Earthing
Input power wiring
Motor
Output to motor wiring
Programming
Proper clearance
Vibration
Table 4.1: Visual Inspection
46
Description
Look for auxiliary equipment, switches, disconnects, or input fuses/circuit breakers that may reside on either the input
power side of frequency converter or the output side to motor. Examine the operation and condition of these items for
possible causes of operational faults. Check the function and installation of pressure sensors or encoders or other
devises that provide feedback to the frequency converter.
Avoid routing motor wiring, mains wiring, and signal wiring in parallel. If parallel routing is unavoidable, try to maintain
a separation of 150-200 mm (6–8 inches) between the cables or separate them with an earthed conductive partition.
Avoid routing cables through free air. For unscreened cabling, run input power and motor power in separate conduit.
Check for broken or damaged wires and connections. Check the voltage source of the signals. The use of screened
cable or a twisted pair is recommended. Ensure the screen is terminated correctly. For unscreened control wiring, run
in separate conduit from power cabling.
Check the operational status of all cooling fans. Check the door filters on NEMA 12 (IP54) units. Check for blockage or
constrained air passages. Make sure the bottom gland plate is installed.
Warnings, alarms, drive status, fault history and many other important items are available via the Keypad on the drive.
The frequency converter interior must be free of dirt, metal chips, moisture, and corrosion. Check for burnt or damaged
power components or carbon deposits resulting from catastrophic component failure. Check for cracks or breaks in
the housings of power semiconductors, or pieces of broken component housings loose inside the unit.
Check for proper installation with regard to electromagnetic capability.
Under specific conditions, these units can be operated within a maximum ambient of 55° C (131° F). Humidity levels
must be less than 95% noncondensing. Check for harmful airborne contaminates such as sulphur based compounds.
The frequency converter requires a dedicated earth wire from its chassis to the building earth. It is also suggested that
the motor be earthed to the frequency converter chassis as well. The use of a conduit or mounting the frequency
converter onto a metal surface is not considered a suitable earth. Check for good earth connections that are tight and
free of oxidation.
Check for loose connections. Check for proper fusing. Check for blown fuses.
Check the nameplate ratings of the motor. Ensure that the motor ratings coincide with the frequency converters. Make
sure that the frequency converter's motor parameters (P-##) are set according to the motor ratings.
Check for loose connections. Check for switching components in the output circuit. Check for faulty contacts in the
switch gear.
Make sure that the frequency converter parameter settings are correct according to motor, application, and I/O con-
figuration.
Frequency converters require adequate top and bottom clearance to ensure proper air flow for cooling.
Look for any unusual amount of vibration that the frequency converter may be subjected to. The unit should be mounted
solidly or the use of shock mounts employed.
High Power Service Manual for Unit Sizes 6x