Kval 979-2, Справочное руководство системы

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Troubleshooting
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979-2
Troubleshooting Electrical Problems
The electrical component systems are designed to expedite the troubleshooting process and minimize
“down time”. In general, component systems have the input or feed functions at the top. Output or load
functions are positioned at the bottom. Most two-voltage electrical panels are designed with the LOW
VOLTAGES on the LEFT, and the HIGH VOLTAGES on the RIGHT. The majority of the system com-
ponents are labeled with numbers that correspond with the electrical prints included in the electrical box
door.
Computer controlled machines have signals on the computer that light up when the input or output func-
tions are energized, respectively. Computer controlled as well as non-computer controlled machines
have white 120V control power terminal strips. This will indicate power supply from the respective cir-
cuits.
Idec controllers also have lights on them for the input and output functions. You can easily find out
which circuits are failing by watching the lights turn on or off. Compare the lights on the IDEC control-
ler to the electrical print to determine what systems are being affected.
If the Power Stops During Normal Operation
1.
Check that the input power disconnect switch is not turned off.
2.
Check that all of the emergency stop buttons are in the normal position.
3.
Lock Out and Tag Out the main power source.
4.
Turn the panel disconnect switch in the off position, open the electrical panel door.
5.
Observe the disconnect switches. Look for loose or broken wires at the disconnect then at all of the
components.
6.
Check for continuity of all fuses with an OHM meter.
7.
Check motor overloads by pressing each white button (usually at the bottom of the panel) in
SEQUENCE,. If one is tripped there will be a slight resistance to touch and a “click” sound as it is
reset.
WARNING
The following checks require the electrical panel to be energized. These troubleshooting checks
MUST BE PERFORMED BY A QUALIFIED ELECTRICAL TECHNICIAN.
1.
Remove lock and tag outs on the main power sources.
2.
Manually close disconnect switches and energize the control circuit or transformer with its respective
switch. Observe that the numbers 1, 3 & 4 are lit on the white lighted terminal strip. This tells you that
there are no overloads or emergency stops tripped.
3.
Most electrical problems are related to mechanical malfunction (e.g., stuck motors, jammed chain,
non tripped limit switches, etc.) The most common failure is an improperly adjusted limit switch. To
check a limit switch, manually operate the limit switch. If the computer terminal strips lights, the
switch needs to be re-adjusted. For more information on the limit switch specifications, see the manu-
facturer’s information. For limit switch adjustment procedures, refer to.
4.
If a solenoid valve is suspected, and not cleared in the air checks section (see), it can be electrically
jumped to check operation.
THE FOLLOWING SHOULD ONLY BE ATTEMPTED BY TRAINED
ELECTRICAL PERSONNEL.