TROUBLESHOOTING (COATER)
PROBLEM
PROBABLE CAUSE
PROCEDURE
Power switch not lit
Machine not plugged in.
Plug machine in
appropriate power supply.
Blown fuse.
Replace fuse.
Controller displays "LBA"
Thermocouple wires loose
or disconnected.
Check connections inside
control box. (See below A)
Heating rod thermocouple
bad.
Replace heating rod. Call
ChemInstruments.
Green OUT lamp lit, PV not
increasing, but coating
head temperature is
increasing
Controller is bad.
Replace controller. Call
ChemInstruments.
Green OUT lamp lit, PV not
increasing, coating head
temperature not increasing
Heating rod wires loose or
disconnected.
Check connections inside
control box. (See Below - B)
Relay loose or bad.
Check relay and replace if
necessary. (See below - C)
Controller is bad.
Replace controller. Call
ChemInstruments.
UNPLUG THE MACHINE BEFORE ATTEMPTING MAINTENANCE PROCEDURES!
ELECTRIC SHOCK MAY OCCUR IF THE MACHINE IS PLUGGED IN!
A – Thermocouple connections:
1.
Each heating rod cable contains four wires. The thermocouple wires are the small red and
white wires. The red wires should be connected to terminal 8 on the back of the Fenwal
heating controller.
2.
The white wires should be connected to terminal 9. Check all six connections.
3.
If “LBA” is displayed on the front of a Fenwal Temperature Controller, this means there
is a break in the thermocouple connection for that controller. If the above connections are
not bad, then the internal thermocouple must be bad, and the entire heating rod must be
replaced.
Note: The thermocouple wires are solid wire, making it easy to break or crack if bent too
severely. When checking these connections, be gentle with this wire.
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