Precision Control Systems 5420 - Manual (Page 13)

Model 5420 ControlIR TM User Manual Maintenance
Maintenance
Troubleshooting
Maintenance and
Trouble Shooting
No routine maintenance is required. The 5420 should be kept clean and
dry. If cleaning is required, unplug unit before cleaning.
Troubleshooting should be done by Qualified Personnel especially if the
5420 needs to be opened up.
SYMPTON ACTION
Heater will not turn on.
- unit is plugged into an energized receptacle
- on/off switch is in the ‘On’ position.
- On 5420 and 5420E versions with
potentiometer control, verify control is not
set to 0.
- On 5420E make sure the timer is not set to
0 when pressing the green button,
additionally the red LED should be flashing
as the timer counts down.
- Heater properly connected to the 5420.
- Lamp burned out in the heater.
- 480 volt 5420E and 5420mA check fuses.
Heater will not turn off.
- Shorted SCR unit always runs at 100%
power. Can be checked: with unit
unplugged, open unit disconnect heater
wires and put an ohm meter across L1 and
L2 if it reads 0 or a small value, the SCR is
defective.
- On the 5420E check for the correct time
range, and LED flashing.
Research, Inc. 10