AEC AP Series Large Dehumidifying Dryer - Manual (Page 15)

Large Dehumidifying Dryers Functional Description 14
Once the main air valve and closed loop regeneration valve are in place, the process air
blower starts. The system monitors the process air blower’s overload, starter auxiliary contact
feedback and air pressure. Loss of any of these items when the process air blower is running
will cause the process air blower and the drying hopper’s process heaters to shut down.
The process air heaters (or gas burners, on gas-fired dryers) will turn on after a delay to allow
the process air blower to accelerate the operating speed.
During normal operation, one set of desiccant beds is connected to the process air circuit
while the other set is being regenerated. When the offline beds are done regenerating, they
will be switched into the process air circuit and the other beds will be regenerated. The
default bed switch setting is based on time. If the Dewpoint Switch option is enabled, the
beds will switch when the process air dewpoint reaches the dewpoint switch point. The
dewpoint option will automatically disable itself and an alarm will be generated if the
dewpoint sensor or related electronics fail.
2-3 Standard Features
Auto Start Timer
The autostart timer is used to automatically start and stop the dryer at the time you specify. It
can be programmed for one start and/or stop event per day for a week. When the Auto Start
Timer is enabled, the dryer will automatically start and stop at pre-programmed times. If the
dryer is stopped due to the Auto Start Timer, the DRYER STATUS message will indicate
that the Auto Start timer is active.
Mechanical Features
; 180ºF – 250ºF Drying temperature range
; High regeneration temperature control safeties
; 13X desiccant (molecular sieve)
; Easy to access process, regeneration, and combustion air filters.
; High pressure centrifugal blower
; Dew point +15º F to –40º F
Electrical Features
; Electrically-actuated air valve
; NFPA79, UL & CUL machinery electrical standards (Electric Dryers) includes:
NEMA 12 controls, components & enclosure
Non-fused electrical disconnect
Solid state relays for heater control
Branch fusing
Lockable power disconnects
Regeneration temperature control
“Process high temp” indication light and audible alarm
7 day timer