AEC WD 350 through WD3000 Dehumidifying Dryers - Manual (Page 75)

Problem Possible cause Corrective action
Fouled dew point sensor
manifold. Clear obstruction. Air should
flow freely through sensor.
Poor dew point performance
(cont’d.)
Dirty filter. Clean or replace filter element.
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.
Nothing displays when the
controller is turned on.
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 .
No setting change possible
on temperature controller. The key protection switch is
set to
ON .
Set the key protection switch
to
OFF .
Input polarity on thermo-
couple is wrong or
connection is wrong.
Properly wire the terminals.
Input-type setting is
incorrect.
Properly set the input with the
input-type selector rotary
switch.
No compensating lead wires
used for extension of the
thermocouple.
Use proper compensating lead
wires and terminals.
Thermocouple and
controller are connected by
wires other than proper lead
wires.
Use a dedicated thermocouple
connector. If a connector is a
metal different from the
thermocouple and controller, a
temperature error may result.
Process thermocouple not
in airflow.
Verify that the thermocouple is
properly installed in the inlet
tube.
Sensor is broken or short-
circuited.
Replace with a good sensor.
The controller is influenced
by noise or other induction.
Separate input wires as far as
possible from the origin of the
noise.
Celsius temperatures used
instead of Fahrenheit or vice
versa.
Check Mode selector switch 6 :
• ON - ºF
• OFF - ºC
Process value is abnormal or
not obtained.
Process value shifted
because the input shift
function is used.
Set input shift value to 0 , or set
mode selector switch 4 to OFF .
Page 74 WDMR and WDFR Series Dehumidifying Dryers