Woodward 1502ES, Руководство по устранению неисправностей

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Solenoid Troubleshooting Guide Manual 36541
22 Woodward
Overload Protection
Internally Switched Solenoids
Woodward recommends using an overload device to protect solenoids from
permanent overload damage. Since customers can choose from a number of
devices available on the market (for example; circuit breakers), specific
troubleshooting procedures cannot be outlined here.
Externally Switched Solenoids
Woodward recommends using a timer device such as a Coil Commander
®
to
protect solenoids from permanent damage. Coil Commanders limit pull coil on-time
to prevent solenoid burnout due to engine overcranking and misaligned linkages.
NOTE
When using a Coil Commander module, there will be a voltage
loss to the solenoid. Application must supply additional voltage
above the minimum hot-solenoid pull-in voltage.
Please consult the factory with questions regarding Coil Commanders.
Solenoid Bench Testing
Use the procedure outlined below to bench test the solenoid.
1. Carefully remove the solenoid from the application. Clean any debris from the
solenoid. Remove and inspect the boot to see if foreign matter may have
entered inside. Remove the plunger and inspect. Clear the cavity of any debris
or foreign material.
Assemble solenoid back together and make sure plunger moves freely. Ensure
the return spring is not preventing the plunger from bottoming out by becoming
“compressed to solid.” Correct situation if needed.
2. Check solenoid coil resistance to determine if the coil is good (refer to Solenoid
Coil Resistance Check section).
If the resistance readings are incorrect, the coil is probably defective. Replace
solenoid and determine why the coil may have burnt out. The probable cause is
usually misadjustment or low voltage.
On internally switched units, the most common reasons for a burnt coil is
misadjustment that prevents the plunger from bottoming out and reaching the
cutoff switch, or low voltage. On externally switchrd units the most common
reason for a burnt coil is overcranking.
3. Arrange, by using a block or some other means, to restrict the stroke of the
solenoid to about 1” maximum. Using a power supply, apply nominal power
(12 Vdc for a 12 Vdc unit and 24 Vdc for a 24 Vdc unit) to the solenoid and see
if the solenoid works.
NOTE: Make sure the power supply is functioning properly.
If the solenoid works, it is acceptable as manufactured. This completes the
bench testing process. Reinstall the solenoid on the application.