Chigo CS-25V3A-MA114A, Руководство по обслуживанию

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componentsthe or checking the next checks;
(9) key is invalid
a), check whether the output pin of the button is normal, or replace;
b), check whether the voltage of display board is 5V, otherwise, check the power supply circuit or
connecting wire;
c), If all above are normal, check whether the main chip is normal, or replace the main chip.
4
） 、
Electric control panel detection
①
red power indicat( LED1) is not bright:
a), check whether the LED1 is damaged, if damaged,please replace the diode;
b), check whether the input and output voltage of the 7812 and 7805 is normal (7812 input 14V, output
is about 12V,7805 input 12V, the output 5V), if damaged,replace the related device or check downward;
c), check whether the bridge rectifier diodes D1-D4 is normal,if the damaged,please replace related
diode;
d), check whether the power supply transformer of input and output is normal (input is about AC220V,
the output is about AC14V), if it is damaged,replace the transformer.
②
Green light LED2 does not shine or the phase sequence protection
a), check whether the light-emitting diode LED2 damaged, if not normal,then the replace the
light-emitting diode;
b), check whether the Q5 (9014) collector voltage is normal, if not normal,then the replace 9014;
c), check whether the relay RY3 is normal, if not normal,then the replace the relay;
d), check whether the resistance of the R7-R10 is normal, if not normal,then the replace the related
resistance;
e), check whether the phase sequence of the three-phase power supply is normal, if not ,then the
replace phase sequence.
③
No-voltage for over-current detection circuit
a), check whether the rectifier diodes D5-D8 is normal, if not normal,replace related diode;
b), check whether the current transformator L1 is normal (resistance of
③ ④
foot should be around a
few hundred ohms),if abnormal,replace it.
④
Over-current protection too long or too short.
Check whether capacity of capacitance E3, E6 is normal (the normal over-current protection is about
20s ~35s), replace if it is not normal,
⑤
appear over-current protection
a), check whether the integrated block LM311 (7) feet IC3 is normal,if not normal,check IC3.if
damage, replace it,
b), check whether triode 9012 is normal.if abnormal,replace it,
c), check the voltage of over-current relay coil is normal (about12V), if it normal,check whether the
relay damage.
⑥ no defrost signal temperature signal (defrosting relay can’t break)
a),check whether the temperature sensor is normal(measure sensor resistance), if the resistance is too
large or too small or even infinite, or 0Ω, then replace sensor;
b), check whether the voltage of the defrost relay coil is normal(about 12V), if it’s normal, check
whether the relay damage.