AEC HE Mass Flow Series Drying hoppers - Manual (Page 54)

HE
• CHE • BCHE Mass Flow Series Drying Hoppers
Page 53
8 Troubleshooting
Problem Possible cause Corrective action
Suction in delivery tube,
pressure from the return
tube (BCHE models). Phase is reversed on power
drop coming into the BCHE
enclosure.
Stop the dryer . Change the
phase of two legs of the three-
phase power drop.
Loss or reduction of process
air temperature.
Process heaters are faulty.
Check for open heaters.
Replace if required.
Solid-state temperature
controller faulty.
Replace.
Process temperature was
adjusted in error by plant
personnel.
Make sure that plant personnel
are aware of the proper
temperature set point. A sign
posted next to the controller is
helpful.
Dirty filters. Clean or replace filters.
Material in drying hopper
cakes, or meltdown occurs.
Process temperature set too
high due to operator error.
Check resin manufacturer’s
data sheet for proper drying
temperature. Make sure plant
personnel are aware of the
correct process temperature
set point.
High temperature alarm not
set properly.
Reset high temperature alarm.
Process set point is out of
acceptable range. Restore temperature controller
to factory pre-sets.
Function set for degrees
Celsius (ºC), set point at
degrees Fahrenheit (ºF).
Verify correct Celsius or
Fahrenheit settings.
Shift valve malfunction. Repair or replace shift valve.
Nothing displays when the
controller is turned on.
The internal mechanism is
not inserted properly into the
housing.
Properly insert the internal
mechanism into the housing.
The power supply is not
connected to its terminals
properly. Properly connect the power
supply to the power supply
terminals.
No power is supplied, or the
supplied power is not within
the specified range. Supply a voltage of 85 to 125
VAC to the power supply
terminals of the controller.
Disconnect switch or Control
Power switch not set to
ON.
Control Power fuse blown.
Check control power fuse for
continuity. Turn disconnect
switch and control power
switch
ON.
Controller not seated in
socket. Verify that the controller is
properly seated in socket.