Accessory Wiring - Chamberlain LiftMaster Professional SW420 Owner's Manual

ACCESSORY WIRING

All inputs are normally open and momentary, except the stop
(N.C.). The following instructions are based upon UL325, and
include recommendations for significant increase in safety.
We strongly recommend that you follow the UL guidelines
presented throughout the manual. Refer to instructions shipped
with optional control devices for mounting, wiring, programming
and adjustment.
24Vac Accessory Power
Can be found at terminals R1 and R2 located on radio terminal
block.
R1
24Vac
J1 Terminals 1 & 5 - Residential Radio (single button) Input
These terminals are intended for use with a radio receiver in a
residential application or as a single button control. This allows
the user to open the gate by activating the remote control when
the gate is closed or between limits. This input also gives the user
the ability to close the gate by activating the remote control when
the gate is on the open limit.
J1 Terminals 2 & 5 - Shadow Loop Input
These terminals are intended for use with a loop detector and is
primarily used on swing gate operators. This input protects cars
by preventing the gate from moving off of the open or close limit
when the shadow loop input is active.
J1 Terminals 6 & 5 - Soft Open
These terminals are intended for use as a general open control.
Accessories that may be wired to this input include: Telephone
Entry Systems, Radio Receiver (Commercial Applications), Exit
Loop Detector, Keypads, 7-Day Timer.
NOTE: Will not override a double entrapment (signalled by the
gate stopped and entrapment alarm on).
Field Wiring Terminals 8 & 5 - Interrupt (Safety) Loop Input
These terminals are intended for use with a loop detector. This
input functions to reverse a closing gate to the open limit.
Latching this input will reset the timer to close.
A D J U S T M E N T
R2 R3 R4
Operator
Field Wiring Terminal Blocks
R1 R2 R3 R4 3
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
J1 Terminal Block
Control Board
HARD OPEN CONROL INPUT
1 2 3 4 5 6 7 8 9 10
SHADOW LOOP INPUT
1 2 3 4 5 6 7 8 9 10
1 2 3 4
3
2
1
6
5
9
8
7
#
0
INTERRUPT (SAFETY) LOOP INPUT
5 8 9 10
20
5 8 9 10 11 12
5
SOFT OPEN
5 6 7 8 9 10
11 12