Specifications

Operation and Management
43MSA1000 Reference Guide
Power Supply/Blower Assembly Indicators
The green indicators on the power supply/blower assembly are on when both the
power supply and the blower are operational. When a power supply or blower
fault occurs, the power supply indicators go off. If the power supply indicators are
off, AC power is not present or there is a complete power supply failure.
The power supply-mounted blowers cool the enclosure by circulating air through
the enclosure. The rate at which air moves (the airflow) determines the amount of
cooling. This airflow is a function of blower speed (rpm). These blowers, under
the control of the Environmental Monitoring Unit (EMU) or the associated power
supply, can operate at multiple speeds. This ensures that when the enclosure
temperature changes, the blowers can automatically adjust the airflow.
If one blower operates too slowly or completely shuts off, the other blower will
begin to operate at a higher speed. At the same time, the error condition is
reported to LCD panel on the front of the controller.
Figure 12: Power supply/blower assembly indicators