Antenna Isolation Kit
K001A3200-2
APPLICATION
The antenna isolation kit protects gate operator components from
possible damage caused by certain wiring configurations. The
installation of some accessories require one of the outputs from
the transformer be shunted to the chassis ground which may blow
the transformer fuse or damage the pre-installed universal
receiver. LiftMaster
®
does NOT recommend connecting the
transformer outputs to the chassis ground, however some third
party accessories require one of the transformer outputs to be
shunted to the chassis ground.
The isolation kit is for use with gate operators models: SL575,
SL585, SL595, HS670, SW420, SW279, and SW490.
CARTON INVENTORY
Nylon Flat Washer. . . . . . . . . . . . . . . . . . . . . . . . . . . . (216A0253)
Nylon Shoulder Washer . . . . . . . . . . . . . . . . . . . . . . . (184A0182)
Fuse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (35-310-032)
Fuse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (35-310-032-1)
TOOLS NEEDED
• Pliers and wrenches
• Screwdrivers
• Diagonal wire cutters
• Wire strippers
• Drill
• 1/2" drill bit
• Digital voltmeter
DETERMINE IF THE ISOLATION KIT IS NEEDED
To determine if the isolation kit is needed for your installation:
1. Disconnect power to the operator.
2. Disconnect the universal receiver (model 850LM) from the
operator. Location varies depending on the operator, refer to
the owner's manual.
3. Connect all other accessories according to the instructions
that came with them.
4. Restore power to the operator.
5. Configure a digital voltmeter to measure AC voltage. Make 3
voltage measurements between the following points: R1-R2,
R1-chassis ground, and R2-chassis ground. Location varies
depending on the operator, refer to the owner's manual.
If there is no voltage between R1-R2, check to see if the
transformer fuse is blown. If the fuse is blown, replace with
the appropriate fuse included in the kit and measure voltage
again.
6. Refer to the table and follow the instructions indicated by
your set of voltage measurements.
To reduce the risk of SERIOUS INJURY or DEATH:
• Disconnect electric power at the fuse box BEFORE
proceeding.
• ALL electrical connections MUST be made by a qualified
individual.
• Upon completion of kit installation, the area MUST be
cleared and secured. At that time the unit may be returned
to service.
WARNING: This product can expose you to chemicals
including lead, which are known to the State of California to
cause cancer or birth defects or other reproductive harm.
For more information go to www.P65Warnings.ca.gov
MEASUREMENT POINTS VOLTAGE
R1-R2
24 VAC
R1-chassis ground
Aprox.
14 VAC
R2-chassis ground
Aprox.
14 VAC
R1-R2
24 VAC
R1-chassis ground
0 VAC
R2-chassis ground
24 VAC
R1-R2
24 VAC
R1-chassis ground
24 VAC
R2-chassis ground
0 VAC
INSTRUCTIONS
Neither of the
transformer outputs are
grounded.
The isolation kit is NOT
needed.
R1 is shunted to ground.
Proceed to TEST THE
UNIVERSAL RECEIVER
FOR DAMAGE.
R2 is shunted to ground.
Proceed to TEST THE
UNIVERSAL RECEIVER
FOR DAMAGE.