Thermo Scientific 3554-35A, Руководство оператора и список запасных частей

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Symptom Possible Cause Possible Solution to Condition
Incubator controller isnʼt functioning, Power switch isnʼt ON or no Place Power ON/ OFF switch inside
no lights etc. power to unit. chamber to ON. Check power outlet by
plugging a known good device into it.
Erratic temperature display Frost buildup. Look for frost Defrost per instructions. If possible
readings above or below set point. inside chamber around operate in 50% Cooling Mode to avoid
evaporator frost buildup.
Temperature uniformity in chamber Frost buildup or airflow Defrost per instruction. If airflow
above specified limit. blocked by samples. blocked by sample containers, remove
some to allow top to bottom airflow.
Temperature readings too high or Controller may need to be Refer to CALIBRATION section of this
too low compared to thermometer. calibrated. manual.
Control goes into power on reset Inadequate line power. Test If line voltage is < 106 VAC while unit is
sequence while operating. Line voltage of outlet to running, then a higher capacity AC line
Incubator while unit is is required.
operating.
Compressor not operating while Compressor stalled and the If line voltage is < 106 VAC while unit is
COOL LED is lit. thermal overloads opens. running, then a higher capacity AC line
Test line voltage of outlet is required.
while operating.
Temperature readings go far Open heater or heater Unplug unit from power then refer to
below setpoint and trigger alarm control relay SSR1. replacing HTR1. Check heater with
at 15°C. OHM meter, about 29 ohms.
Temperature readings go far above Defective cooling relay, If compressor isnʼt running while Cool
setpoint and triggers alarm at 40°C compressor or shorted LED is on then replace K2 relay. If
or above. heater SSR1. Check if compressor is running and evaporator
compressor is running, if so isnʼt cold then cooling system needs
touch evaporator in chamber repair. If evaporator is cold then SSR1
it should be cold. may be shorted.
Controller display works but heater, Safety relay K1 not closing. K1 relay may need replaced.
compressor and chamber fan donʼt.
Display EEE/99.9 Open sensor or sensor Check sensor connection at controller.
connection. Check sensor with ohm meter, 100
ohms at 0°C and 110 ohms at 25°C.
Cabinet temp. above 63°C. If temps inside the chamber seem
Heater held on. excessive, check SSR1 for short
Display EEE/99.8 Shorted sensor or connection Check sensor connection at controller.
Cabinet temp below -13°C. Check for Heat LED and if lit, check
Heater not working heater circuit including SSR1
Display EEE/temp Incubator needs defrosted See erratic temperature display readings.
Troubleshooting
1. Temp Limit = Temp (±3°C or more from setpoint) & (> 40°C or <15°C), safety relay opens.