Chamberlain DH Addendum

APPLICATION REQUIREMENTS
This modification is available to models H and J Logic operators.
FUNCTIONS
This modification stops the operator from running when extra
tension is sensed on the door from the mechanical door lock,
obstruction, or extensive binding.
OPERATION
When the lock sensor senses an excessive load while running the
open cycle from the close limit, the lock sensor will stop the
operator. Press the close button and run the operator until it
shuts off (to unlock the door when the load is removed).
NOTE: Refer to lock sensor addendum for adjustment. For all
other installation instructions refer to owner's manual provided
with operator.
FINE ADJUSTMENT
• To increase opening force, tighten the wing nut.
• To decrease opening force, loosen the wing nut.
COURSE ADJUSTMENT (IF REQUIRED)
1. Release spring pressure on pivot arm.
2. Loosen but do not remove two mounting screws.
3. Fully tension final reduction chain and rotate lock sensor until
switch is in activation mode.
4. Tighten mounting screws (2) to secure lock sensor position.
5. Repeat fine adjustments.
Final Reduction Chain
Final Reduction Chain
01-31376C
L O C K S E N S O R A D J U S T M E N T
Chain Idler Sprocket
Chain Idler Sprocket
must engage top side
must engage top side
of reduction chain.
of reduction chain.
Mounting Screws
© 2010, The Chamberlain Group, Inc.
All Rights Reserved
Models DH, DJ, and DHJ
Moving parts may cause SERIOUS INJURY. Keep hands
CLEAR of sprockets, chains, and other moving parts when
making adjustments.
Lock Sensor Assembly
Lock Sensor Assembly
Mounting Screws
AVERTISSEMENT
ATTENTION
ADDENDUM
LOCK SENSOR
WARNING WARNING
CAUTION
Lock Sensor Switch
Lock Sensor Switch
(held to normally closed).
(held to normally closed).
To adjust opening force
To adjust opening force tighten
tighten or loosen adjustment
or loosen adjustment on wing nut
on wing nut accordingly.
accordingly.