Trouble

Cause

Remedial action

The room temperature compensation input to the temperature controller was disconnected. The chamber has been stopped.

The sensor is loosely connected to the RTD terminal on the SCP-220(ANA-LOG) temperature controller board or there is an open circuit on the SCP-220 board.

Turn control power OFF from the
POWER key and resume testing. If the same alarm occurs again, call for service.

The dry-bulb input to the temperature controller was disconnected. The chamber has been stopped.

The sensor is loosely connected to the TD terminal on the SCP- 220(ANA-LOG) temperature controller boardor there is an open circuit in the connected thermocouple.

Turn control power OFF from the
POWER key and resume testing. If the same alarm occurs again, call for service.

The wet-bulb/humidity input to the temperature controller was disconnected. The chamber has been stopped.

The sensor is loosely connected to the TW terminal on the SCP-220(ANA-LOG) temperature controller boardor there is an open circuit in the connected thermocouple.

Turn control power OFF from the
POWER key and resume testing. If the same alarm occurs again, call for service.

A refrigeration circuit monitor channel (Ai5 12ch) to the temperature controller was disconnected. The chamber has been stopped.
If the backup mode is ON and the chamber has multiple refrigerators, only the affected refrigerator stops while all others continue running.

Either the sensor is loosely connected to the Ai5 12 terminal on the SCP-220(ANA-LOG) temperature controller boardor there is an open circuit in the connected thermocouple.

Turn control power OFF from the
POWER key (wait for the test end if back up mode is ON) and resume testing. If the same alarm occurs again, call for service.

The temperature inside the chamber has risen above the upper deviation limit. The heater has been stopped until temperature returns within range.

Either specimens inside the chamber are generating heat or the upper deviation limit is set too low.

Remove the heat-generating specimens and/or set the upper deviation limit about 10°C. When temperature returns within range, normal control is restored automatically. The alarm can be cleared by pressing the Buzzer key.

The temperature inside the chamber has risen above the absolute high limit. The chamber has been stopped.

Either specimens inside the chamber are generating heat or the absolute high limit is set too low.

Turn control power OFF from the
POWER key. Then, remove the heat-generating specimens and/or set the absolute high limit about 15°C higher than the target temperature. Resume testing. If the same alarm occurs again, call for service.

AL03

The temperature inside the chamber has dropped below the absolute low limit. The chamber has been stopped.

Possible causes include infiltrating of outside air, excessive cooling, the effects of cooling sources inside the chamber, and the absolute low limit being set too high.

Turn control power OFF from the
POWER key and check the chamber door and cable ports. If the refrigerator is on manual control, correct the capacity setting. If cooling sources are overcooling the chamber, reduce their number. Also, correct the absolute low limit setting as necessary. Then, resume testing. If the same alarm occurs again, call for service.

The temperature inside the chamber has risen above the overheat protector setting (instrumentation panel). The chamber has been stopped.

Either specimens inside the chamber are generating heat or the overheat protector is set too low.

Turn control power OFF from the POWER key. Then, remove the heat-generating specimens and/or correct the overheat protector setting. Resume testing. If the same alarm occurs again, it is possible the thermal fuse has blown. Call for service.

The built-in temperature switch of the air circulator motor (water circuit [heat exhaust] compartment) tripped because the motor is abnormally hot. The chamber has been stopped.

Overloaded air circulator motor

Leave the chamber OFF until the air circulator cools down. Then, turn control power ON from the POWER key and resume testing.

The high pressure switch tripped because refrigerator pressure was high. The chamber has been stopped..

The refrigerator's operating pressure is higher than specified.

Turn control power OFF from the
POWER key. With air-cooled refrigerators, check if the condenser filter is clogged. Correct as necessary and resume testing. If the same alarm occurs again, call for service.

The thermal relay tripped because refrigerator operating current was high. The chamber has been stopped.

The refrigerator's operating current is higher than specified.

Turn control power OFF from the
POWER key. With air-cooled refrigerators, check if the condenser filteris clogged. Correct as necessary and resume testing. If the same alarm occurs again, call for service.

The compressor temperature switch tripped because refrigerator surface temperature was high. The chamber has been stopped.

The refrigerator's surface temperature is higher than specified.

Turn control power OFF from the
POWER key. With air-cooled refrigerators, check if the condenser filteris clogged. Correct as necessary and resume testing. If the same alarm occurs again, call for service.

The thermal relay of the condenser fan tripped because fan operating current was high. The chamber has been stopped.

The condenser fan motor operating current is higher than specified.

Turn control power OFF from the
POWER key and check if the condenser filter is clogged. Correct as necessary and resume testing. If the same alarm occurs again, call for service.

One of the temperature controller channels (Ai5 12ch) that monitor the refrigeration circuit was disconnected. The chamber has been stopped. If the chamber has more than 1 refrigerator and the backup mode is ON, only the affected refrigerator will shut down, while the chamber will continue running using another refrigerator.

Frost buildup, compressor trouble or a refrigerant leak are all possible causes.

After testing ends, turn control power OFF from the POWER key. With air-cooled refrigerators, check if the condenser filter is clogged. Correct as necessary and resume testing. If the same alarm occurs again, call for service.

The heater's circuit protector tripped because operating current was high. The chamber has been stopped.

Short-circuit or overcurrent in the heater circuit

Set the main power switch (leakage breaker) in the OFF position and reset the humidifier's circuit protector on the electric parts chassis(electric parts compartment). Then, reactivate the system from the main power switch followed by the POWER key, and resume testing. If the same alarm occurs again, call for service.

A reverse or open phase was detected in the 3primary power supply connection. The chamber has been stopped.
* A reverse or open phase can be detected even when the POWER key is in the OFF position.

Primary power supply is not correctly connected to the chamber.

An incorrect power supply can seriously affect chamber components.
Set the main power switch (leakage breaker) in the OFF position, and check/correct primary power supply phase alignment and connections. Then, reactivate the system from the main power switch followed by the POWER key, and resume testing. If the same alarm occurs again, call for service.

Trouble was detected in an external unit. The chamber has been stopped.

For information on external unit troubles, see the instruction manual that came with the external unit.

Turn control power OFF from the
POWER key. Then, take the remedial action described in the instruction manual of the external unit. Resume testing. If the same alarm occurs again, call for service.

The humidifier's circuit protector tripped because operating current was high. The chamber has been stopped. If the backup mode is ON, humidity tests are suspended, but temperature tests continue.

Short-circuit or overcurrent in the humidifier circuit.

Set the main power switch (leakage breaker) in the OFF position and reset the humidifier's circuit protector on the electric parts chassis (electric parts compartment). Then, reactivate the system from the main power switch followed by the POWER key, and resume testing. If the same alarm occurs again, call for service.

The humidity inside the chamber has risen above the absolute high limit. The humidifier has been stopped until humidity returns within range.

The absolute high limit is set too low.

Set the absolute high limit setting about 10%RH higher than the humidity SV. When humidity returns within range, normal control is restored automatically. The alarm can be cleared by pressing the Buzzer key.

The humidity inside the chamber has dropped below the absolute low limit. The heater has been stopped and refrigerator capacity decreased to the minimum (turned OFF in some cases) until humidity returns within range.

The absolute low limit is set too high.

Set the absolute high limit setting about 10%RH higher than the humidity SV. When humidity returns within range, normal control is restored automatically. The alarm can be cleared by pressing the Buzzer key.

Humidifying tray water level does not lower even though water is being drained. The chamber has been stopped.

Either the drainage pump has malfunctioned or the drainage line is clogged.

Check the water circuit drainage pump (water circuit compartment) is functioning correctly, and check for clogs in the drainage line and clean as necessary. Then, resume testing. If the same alarm occurs again, call for service.

The main water tank is empty. The humidifier has been stopped.

The main water tank is empty.

Refill the auxiliary water tank and set it on the main water tank. Then, resume testing. After water has been sufficiently supplied to the main water tank, the alarm can be cleared by pressing the Buzzer key.
If the same alarm occurs again, call for service.

The humidifying tray did not fill within the specified amount time at the start of humidity testing. The chamber has been stopped. If the backup mode is ON, humidity tests are suspended, but temperature tests continue.

The strainer on the humidifying water supply circuit is either clogged or the circuit is leaking, or water supply pressure is too low.

Check the humidifying water supply circuit (wait for the test end if the backup mode is on) and correct as necessary. Then, resume testing. If the same alarm occurs again, call for service.

The humidifying tray did not fill within the specified amount time during humidity testing. The chamber has been stopped. If the backup mode is ON, humidity tests are suspended, but temperature tests continue.

The strainer on the humidifying water supply circuit is either clogged or the circuit is leaking, or water supply pressure is too low.

Check the humidifying water supply circuit (wait for the test end if the backup mode is on) and correct as necessary. Then, resume testing. If the same alarm occurs again, call for service.

During humidity testing, the wet-bulb (measures relative humidity) rose above the specified temperature. The humidifier will continue as is, but humidity control might destabilize and trigger a humidity alarm.

The wet-bulb wick (gauze) inside the chamber may be dry.

Stop the chamber and replace the wick. After wet-bulb temperature returns within the specified range, the alarm can be cleared by pressing the Buzzer key.

The auxiliary water tank is empty. The humidifier will continue on the water in the main tank, but it will eventually stop unless water is replenished.

The auxiliary water tank is empty.

The instrumentation detected communication trouble between the CPU board and display board. Or the instrumentation detected system trouble. The chamber has been stopped.

Communication error between the CPU board and display board

Reactivate the system from the main power switch (leakage breaker) and resume testing. If the same alarm occurs again, call for service.