- 40 -
Trouble
Cause
Measure
A
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.
Overcool alarm is
indicated.
- Alarm message
[OVC] blinking
All controls are
continued
After the measured temperature
reached to the set-point, it rise 5
℃
or
more than the set temperature.
This alarm occurs a little later on
when the measured temperature is
within
±
1
℃
range of set temperature.
Wait awhile until the measured
temperature reaches to
±
1
℃
range
of set temperature, immediately after
you set temperature or defrost
operation.
Also, it may occur when the door is
opened or closed, or any obstruction
blocks the ventilation port of chamber.
The alarm indication can be cleared
by [Clear] key.
Power failure
alarm is indicated.
- Alarm message
[OFF] blinking
All controls are
continued
Power failure occurs while controlling
and the unit recovers.
Or the unit is shut down by the power
switch without stopping the operation
by [Run Stop] key, and the unit started
up again.
The operation is continued from the
time of shutdown with keeping
elapsed time, set temperature and
humidity.
The alarm indication can be cleared
by [Clear] key.
Humidity control
fault is indicated.
- Alarm message
[HU1] blinking
All controls are
continued
Although the normal humidity control
is continued, the measured humidity
exceeds
±
20%RH range of the set
humidity in 60 minutes.
It is thought to be aftereffects of sharp
change of set value of temperature
and humidity, shortage of wick
moisture, or freeze-up of wick,
obstructions of ventilation port, or
storage of hygroscopic or evaporable
samples.
Or the humidification tray (top/bottom)
becomes empty and boil-dry, and the
heater for humidification (top/bottom)
is stopped automatically. or the heater
fault occurs, and it causes above-
mentioned status.
Check the setting, wet-bulb wick
condition, water supply status, and
samples in the chamber.
The alarm indication can be cleared
by [Clear] key.
Cooling fault is
indicated.
- Alarm message
[COL] blinking
All controls are
continued
Although the refrigeration unit works
and the heater stops, the measured
temperature cannot be lowered 1
℃
per following period.
The alarm may occurs because the
temperature is influenced by the
humidification control when the
humidity is out of its control range or
the ambient temperature is high. Set
the humidity within the control range,
and lower the ambient temperature.
Check the maximum cooled
temperature in the cooling curve with
35
℃
room temperature,
If the refrigeration unit does not work
or you hear abnormal noise from it,
the unit must be repaired.
The alarm indication can be cleared
by [Clear] key.
- Measured temp.: -5
℃
or higher
→
30 minutes
- Measured temp.: less than -5
℃
→
60 minutes
Temperature
gradient fault is
indicated.
- Alarm message
[PRG] blinking
All controls are
continued
The measure temperature deviates
from the
±
5
℃
range of the target
point during the gradient control, and it
is kept for 10 minutes or longer.
Or the setting of gradient exceeds the
control performance of this unit.
And the alarm may occur when the
door is opened or closed.
[Example]
When the alarm occurs in the segment
5 of Program 3, [PRG3S5] is shown,
The alarm indication can be cleared
by [Clear] key.
