Chigo CS-25V3A-MA114A, Service Manual

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3)
、
insulating property
Testing method:
check by multimeter, select the appropriate range. one pen contacts with input terminal,the other contacts
with body.if the resistance is ∞ or tens of thousands of ohms,means insulating property is good.if the
measured resistance of the smaller or 0,means core screen has been destroyed.
4), run on power
Testing method:
connect the four-way valve and the electrical components,connected to rated power; change the mode
between cooling and heating mode,check whether the four-way valve could correctly change.
Fault judgement:
if the four-way valve could not change correctly, means four-way valve bad or wire partial short-circuit
fault.
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Testing method:
Visual inspection: check whether the appearance of step motor is burnt, rust. If have,that means the
winding of motor is broken.In the case of non-power,hand knob step motor's output shaft,if there exist
strange noise,that may be caused by driving wheel not matching or loose for connecting piece.
2)
、
Check torque
Self-positioning Torque:
under the action of this torque, step motor should not lose, not jitter, non-skid.
3)
、
Resistance test
①
short circuit: Measure resistance of each winding by universal meter, if the resistance value is
lower than the standard, the winding may short circuit.
②
open circuit: Measure resistance of each winding by universal meter, if the resistance value is
infinite, the compressor winding may open circuit.
4)
、
Check on running
Testing method:
make sure
step motor running with load, there shouldn’t be unusual noise. if there is unusual
noise
,it
is caused by rust or wear. If the step motor does not work, most is due to open coil, short circuit, or rust.
5)
、
insulating property
T esting method:
check by multimeter, select the appropriate range. one pen contacts with
input terminal
,the other
contacts with
body of step motor
.if the resistance is
∞
or tens of thousands of ohms,means
insulating
property is
good.if the measured resistance of the smaller or 0,means
core screen
has been destroyed.
6)
、
electrical performance checking
Testing method:
use needle nose pliers or similar tool clamp output shaft of the motor,rotate it clockwise.at the same
time, choose AC 20V voltage,then connect two pens with step motor input end.after rotating the output