EP Equipment CPD30L1-B, Service Manual

Page: 53 / 235

41
REV. 05/2020
DRIVE SYSTEM
5
Temperature Sensor
Temperature sensor is used to monitor motor
temperature.
Measure the resistance between pin connector
(39#) and (20#) with a multimeter to identify if
the temperature sensor is normal.
As shown in the following table:
Resistance
Measurement
Judgment
With readings Normal
0 Ω
Sensor short circuit
(replace the motor)
∞
Ω
Sensor open circuit
(replace the motor)
Checking
Speed Encoder
Speed encoder is used to detect the speed
of the motor and covert the speed into fixed
signals.
- Check if the motor encoder and the appear-
ance of cables are in good condition, and if
the plug connection is secure.
- Remove the speed encoder and check its
sensing surface for wear.
5.2.3 Checking and Testing
U, V, W Terminals
-
Identify if the motor windings are normal
through measuring the resistance of U-V, V-W,
and U-W respectively, if there is short circuit
or breakage;
as shown in the following table:
Due to the small size of windings, when measu-
ring with a multimeter, put it on a low resistance
range.
Resistance
Measurement
Judgment
With readings,
but very low
Normal *
0 Ω
Winding internal short circuit
(replace the motor)
∞
Ω
Winding internal open circuit
(replace the motor)
* The difference between the resistance values
measured at U-V, V-W and U-W shall not be
greater than 2%.
CAUTION
- Identify if there is leakage current through
measuring the resistance between U, V, W
and motor housing respectively.
as shown in the following table:
Resistance
Measurement
Judgment
0 Ω
Leakage current
(replace the motor)
∞
Ω Normal
*
* For normal motor, U, V and W terminals are
insulated from motor housing.