3-4
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Safety and alarm functions
This product is equipped with the following safety
features and alarm functions. If you face any trouble,
please refer to "Troubleshooting" on page 49.
Safety features
-15-
Alarm functions
・
Setting value for over heat protector is too low.
・
Temperature controller, SSR or the fan in the air
jacket is impaired, which made the temperature
of over heat protector raise too high.
・
Electric leakage occurs or excess current flows.
Reasons why the device works.
Operation
Safety feature
Turns off the unit and cuts off the
power.
Turns off the heater when the
temperature exceeds the setting
temperature of over heat protector
and over heat lamp lights up.
Residual current device
Over heat protector
・
Setting value for over heat protector is too high.
・
Temperature controller, SSR or the fan in air jacket is
impaired, which makes the overcool protector lowers.
・
The unit is defrosted.
Turns off the refrigeration unit when the
temperature is lower than the setting
value of overcool protector, which makes
the overcool lamp light up. The unit will
be controlled when the temperature rises.
Overcool protector
・
Setting value for over heat protector is inappropriate,
which makes temperature controller, SSR or fan in
the jacket impaired and raise the temperature
（
reaches up to upprox.70
℃
.
）
Turns off the heater and over heat lamp
lights up. The unit will be controlled again
when the temperature lowers.
Over heat protecting
thermostat
Reasons why alarm is activated.
Alarm display and operations
Alarm name
Upper temperature
limit alarm
・
Buzzer beeps for 15 seconds.
・
Control will be continued.
・
Alarm display
Operating conditions
Alarm is activated when the temperature in the
chamber exceeds
「
Setting tempsetting
temperature for upper temperature limit alarm
」
temporarily.
Releasing alarm
・
Alarm will be released automatically when the
measured temperature is within the range of
「
Setting temperature
＋
Setting temperature for
upper temperature limit alarm
」
.
・
Alarm will be also released by
［
Set
］
key.
※
Setting temperature for upper temperature limit
alarm can be changed. Please refer to How to
operate upper temperature alarm" on page 42.
・
Buzzer beeps for 15 seconds.
・
Control will be continued.
・
Alarm display
Lower temperature
limit alarm
Operating conditions
Alarm is activated when the temperature in the
chamber lowers than
「
Setting
tempsetting temperature for
low
er
temperature limit alarm
」
temporarily.
Releasing alarm
・
Alarm will be released automatically when the
measured temperature is within the range of
「
Setting temperature
＋
Setting temperature for
lower temperature limit alarm
」
.
・
Alarm will be also released by
［
Set
］
key.
※
Setting temperature for lower temperature limit
alarm can be changed. Please refer to How to
operate lower temperature alarm" on page 43.
↑↓
Displays alternately
PV
Alarm
Heating
SV
℃
h.m
PV
Alarm
Heating
SV
℃
h.m
Defrost
Defrost
Over load relay
maintaining circuit
for refrigeration unit
Refrigeration unit performs over load
operation (over heat) or starts up,
which makes alarm lamp light up and
indicates alarm display and stops
refrigeration unit.
・
Refrigeration unit performs over load operation (over
heat) or starts up.
・
Heat load exceeds the capacity of cooling capability
and the temperature in the chamber rises too high.
・
Ambient temperature is higher than 35
℃
.
・
Voltage is too low.
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19.5
AL-H
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Displays alternately
PV
Alarm
Heating
SV
℃
h.m
PV
Alarm
Heating
SV
℃
h.m
Defrost
Defrost
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19.5
AL-Ｌ
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