Chamberlain CB24 Owner's Manual page 12

LOOP INPUTS (P11) (see page 13)
Shadow Loop Input Terminal and Common
This input protects cars by preventing the gate from moving off
of the open or close limit when the shadow loop input is active.
Interrupt Loop Input Terminal and Common
This input functions to reverse a closing gate to the open limit.
Latching this input will reset the timer to close.
PHOTO/EDGE INPUTS (P6-7-8 and 9) (see page 13)
Terminal P6 – Close Edge
This input will reverse a closing gate. It will disable the Timer-to-
Close if that feature has been enabled. Activating this input while
the gate is opening will have no effect.
Terminal P8 – Open Edge or Photo Eye
If an Open Edge device or a Retro-Reflective Photo Eye has been
connected to Terminal P8, then this input will reverse an opening
gate for 2 seconds then stop. Activating this input with an Open
Edge device or a Retro-Reflective Photo Eye connected to
Terminal P8 while the gate is closing will have no effect.
If a Chamberlain Pulsing Photo Eye has been connected to
Terminal P8, then this input will pause an opening gate until the
obstruction has been removed. Upon removing the obstruction,
the gate will continue to open. Activating this input with a
Chamberlain Pulsing Photo Eye connected to Terminal P8 while
the gate is closing will have no effect.
Terminal P7 – Open Photo Eye
This input will pause an opening gate until the obstruction has
been removed. Upon removing the obstruction, the gate will
continue to open. Activating this input while the gate is closing
will have no effect.
See page 15 for Dip-Switch settings.
Unused safety inputs may require a wire bridge (JUMPER)
Terminal P9 – Close Photo Eye
This input will reverse a closing gate to the open limit. Activating
this input while the gate is opening will have no effect. The Timer-
to-Close will not reactivate at the open limit.
NOTE: Make sure the positive (+) and negative (-) wires are
wired correctly.
SHADOW
INTERRUPT
CHGR COM
OVLD
F1 20A 32V
FUSE
BATT 2 BATT 1
OPEN
CLOSE
EDGE
OPEN EDGE
PHOTO
OPEN
PHOTO
CLOSE
PHOTO
12
LOOP
INPUTS
SHADOW LOOP
INTERRUPT LOOP
COMMON LOOP
or
or
or
771E
771E
771E