Chamberlain Security+ 3900PLD - Manual (Page 13)

13
INSTALLATION STEP 8
Mount the Standby Power Unit (SPU)
(Not Provided)
If the optional 475LM Standby Power Unit is part of this
installation it should be installed at this time.
•
The SPU can be mounted to either the ceiling or a wall
within 3' (.9 m) of the motor unit.
• Position the SPU as desired to a structural support
(ceiling joist or wall stud).
• Attach the SPU to the support using the mounting holes
on either side of the SPU.
• Secure the SPU using the 1-1/2" lag screws (2) provided
with the SPU unit.
• Connect the SPU cord into the connector on the bottom
of the motor unit.
• Follow all instructions included with the 475LM unit to
test for proper operation and testing of the SPU. SPU Cord
Connector
475LM Standby
Power System