Railway Equipment 934, Operating Manual

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P/N R9340-0104 20 © 2010 RAILWAY EQUIPMENT CO.
REV B
5/11
C. FAULT CONDITIONS
1. MAJOR VOLTAGE FAULT
Major voltage fault is caused by a mismatch in control modules. If
a module set up for 230 volts is used in a 460 volt EHAB, this fault
is set. To correct this, chance the unit type screen (found on the
SET POINT menu) to match the voltage and phase of the EHAB
unit.
2. OVERTEMP FAULT
Overtemp fault is caused by high heat duct temperature. Possible
cause of this fault is low air flow. The duct work should be
checked for any obstructions. When an overtemp fault occurs the
heat contactor will be disabled. After the overtemp sensor cools
down, the overtemp will clear and the heat will resume.
3. SAIL SWITCH ON FAULT:
Sail switch on fault occurs during startup when the processor
checks the status of the airflow switch. If the airflow switch is
closed or shorted the blower motor will turn on and the blower will
run a 4-minute purge to try to clear the airflow switch. The motor
will then shut off and sit idle for 1 minute. Upon completion of this
5-minute cycle, the blower will once again check the airflow
switch for proper operation. If the airflow switch still shows that it
is closed, the 5-minute loop will run again. This will repeat until
fault is cleared or blower is no longer called for.
4. SAIL SWITCH OFF FAULT:
Sail switch off fault is set when blower is running and air flow
switch remains open. After the fault is set, the blower motor will
run a 4-minute purge to try to clear the airflow switch. The motor
will then shut off and sit idle for 1 minute. Upon completion of this
5-minute cycle, the blower will once again check the airflow
switch for proper operation. If the airflow switch still shows that it
is open it will run the 5-minute loop again. This will repeat until
fault is cleared or blower is no longer called for. Things to check
for are free movement of the sail switch and obstructions in the
duct work.
5. MOTOR OVERLOAD, RESET OVERLOAD DEVICE:
High motor current will trip the motor overload on the control
panel. This device is connected to the bottom of the motor
contactor on the control panel. Reset by pressing the red button on
the device. Check unit for high motor current, bad bearings, or
obstructions in the blower wheel.