AEC HE Mass Flow Series Drying hoppers - Manual (Page 55)

Page 54 HE
• CHE • BCHE Mass Flow Series Drying Hoppers
Problem Possible cause Corrective action
Process value is abnormal or
not obtained.
Input polarity on thermo-
couple is wrong or
connection is wrong.
Properly wire the terminals.
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 thermo-
couple connector. If a
connector is a metal different
from the thermocouple and
controller, a temperature error
may result.
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. Setup mode level 2 display
d-U. S-V display shows
setting.
Thermocouple is not in air
path.
Verify that the thermocouple is
properly installed in the inlet
tube.
Premature heater failure.
Dirty filters. Clean or replace filters.
Voltage spikes. Install surge supressor.
Poor dew point performance.
Contaminated desiccant. Replace desiccant.
Regeneration heater failure. Replace heater.
Dirty filters. Clean or replace filters.
Regeneration high
temperature thermostat
failure.
Replace thermostat.
Service Notes