Pub. No. OM-A-75 REV. 4 — March 2006
5
H.
Connect electric power, according to the wiring
diagram and nameplate power requirements, to the
electrical terminals. The refrigerated dryer is
designed to run continuously; therefore, it must be
wired separately from the air compressor cycling
switch. The dryer must not cycle with the air
compressor. All units are prewired internally.
Follow the recommendation on the electrical
drawing for the fuse size and the incoming power
details. Connect the power to the air dryer only
through a properly sized fused disconnect switch.
Wiring to the dryer must meet the national
(NEC) and local code requirements. Check
the voltage specified on the nameplate to
the electrical power connecting to the
dryer. Electrical connections must be made
by an electrician.
SCROLL COMPRESSOR
Air dryers with a scroll compressor are uni-
directional and to function properly they
must be phased correctly. To turn the com-
pressor clockwise, use a phase sequence
indicator to determine phases A, B, & C. For
proper compressor rotation, connect the
power supply phases A to L1, B to L2, & C to
L3. Reverse rotation may damage the com-
pressor. If the compressor is wired back-
wards the compressor will be noisy, vibrate
excessively and the oil sump will become
warm. The suction pressure will begin to
rise, and the discharge pressure will fall.
