42
Cause
Corrective Action
Defective motor
speed controller
(only applicable to
Stable flow Speed
control)
•
Switch on the blower on the cabinet.
•
Please refer to the component layout at the beginning of this section to locate the
speed controller. This is indicated by N1 in the layout.
•
If the blower still does not work, Switch off the cabinet.
•
Disconnect the connector to the stableflow output.
•
Switch on cabinet. Check Voltage output of stable flow. If no voltage output / small
output voltage is measured, try to adjust speed to maximum. When voltage output is
not detected, the stable flow is defective.
•
Replace the defective stableflow. Proceed to the next step.
Motor failure
WARNING:
The cabinet MUST be decontaminated before opening the plenum cover
.
•
Check for physical damage.
•
Will the motor rotate?
•
Check wiring.
•
Replace the blower.
Problem 5: Airflow Failure (AIRFAIL) – alarm is triggered
Cause
Corrective Action
External air
interference
•
Ensure that there are no external sources of airflow disturbance close to the sensor.
Check vents, lights, ceiling too close, etc.
•
If there is no external air interference, Proceed to the next step.
Blocked cabinet
grille
•
Ensure that the air grilles inside the cabinet are not blocked and that the cabinet is not
excessively loaded.
•
If there is no blockage in air grilles, Proceed to the next step.
Low building
supply voltage
(if new cabinet,
check this first)
•
Refer to the electrical layout and find motor voltage Test Point shown in Figures 4-2 and
4-3.
NOTE:
The voltage adjustments should only be carried out by a qualified Certifier
.
•
For a new cabinet, if the motor voltage is lower than the Nominal Voltage value
recorded in the factory test report, adjust the speed controller to get output voltage to
blower as specified in the Test Report – Test Conditions Documentation Sheet.
•
For cabinet that has been used for more than 1 year, refer to last motor Nominal
Voltage from last certification report or if not available, measure the actual airflow on
cabinet and increase motor voltage accordingly to achieve nominal airflow velocity.
•
If supply voltage is same as Nominal voltage, proceed to the next step.
Defective
airflow sensor
power supply –
Switch Mode
Power supply
(SMPS) (Only
when SMPS
(item code
•
Cabinet must be turned on to perform this test.
•
Locate the 5 pin connector.
•
On the BACK side of the 5 pin connector measure the DC voltage between Green (pin 5)
and Black (pin 4). Measure on the side, away from the SMPS. See Figure 1-4 and 1-5.
•
The voltage should be in range of +12VDC ± 10%.
•
Voltage on the other side of the 5 pin connector does not need to be measured.
•
If out of range, check incoming power to the SMPS Molded cord – check the terminal
where the cord is connected. The input should be ±10% of the cabinet voltage
Figure 4-7. Measure ECMS Supply
Figure 4-9. Measure PWM Output
Figure 4-8.ECMS no Display
Summary of Contents for Class II
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