American Dryer Corp. AD-200 Clothes Dryer User Manual


 
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3) 24 VAC Transformer
The 24 VAC transformer consists of fuse 1 (F1) and fuse 2 (F2) which is the primary fusing for the
transformer. For the proper rating of these fuses refer to the specific electric diagram. The transformer
is located in the right hand electrical cabinet.
Dryer models with an optional Sprinkler System have an energizing stop relay which will disable the
dryer functions (shut the dryer down) in the event of a fire.
IF THE SPRINKLER SYSTEM IS NOT
ENERGIZED (POWERED) THE DRYER WILL NOT OPERATE. The Energizing Stop Push
Button is located on the front right electrical panel. On 2-Door models this Energizing Stop Push
Button is located on the right rear side of the electrical panel (when viewed from the rear).
On dryer models manufactured for 208 volt or 240 volt electric service, the step down voltage for the
Phase 5 microprocessor controller (computer) and the Programmable Logic Controller (PLC) is
supplied from the primary side of the 24 VAC transformer. On dryers that are manufactured for 380
volts and higher, there is an additional secondary on the transformer that is used to supply the step
down voltage required to operate the Phase 5 microprocessor controller (computer) and the
Programmable Logic Controller (PLC) through fuse 4 (F4).
4) 24 VAC Control Circuit
The secondary side of the 24 VAC transformer supplies 24 VAC to various control circuits through
fuse 3 (F) and a 20-amp fuse or an 8-amp fuse (fuse amperage [rating] is dependent on the date that
the dryer was manufactured).
The first circuit is the control voltage on/off. Control voltage ( 24 VAC) goes through the "Master
Off" (normally closed) switch and supplies voltage to the "Master On" (normally open) switch. When
the "Master On" switch is momentarily engaged, the master control relay (MCR) engages. This
closes the MCR-A contactor (which is in parallel with the "Master On" switch) which will keep the
MCR enabled. If the power is interrupted or the "Master Off" switch is pressed the MCR will
disengage. The MCR-B contactor supplies power to the rest of the 24 VAC circuits.
For dryers manufactured with Automatic Doors - the supply air enables' purpose is to relieve pressure
on the automatic door pistons when an energizing stop is engaged.
5) Safety Circuits
The following circuit branches are to verify various safeties, if ALL conditions are met ...
a) The first two (2) items are the Auxiliary Contact located on the blower (impellor/fan) motor and
the Tumbler (basket) Motor Overload. If either of these devices trip, it will open up the safety
circuit thereby preventing the dryer from operating.
b) Front Doors Closed circuit branch ...
There are two (2) magnetic proximity switches mounted in the door closed position and a magnet
mounted on top of the doors. When this magnet aligns with the proximity switch, the contacts in
the proximity switch close. When both doors are closed, the front doors closed relay (CR2) turns
on ...
(1) There are two (2) sets of contacts in the relay... one (1) set of contacts are in the dry enable
circuit branch and the other set go to the PLC input front doors closed.