Troubleshooting; Diagnostic Leds - Chamberlain LM21AFCB Owner's Manual

Detector Open
(Yellow)
Detector Short
(Red)
Figure 11 - Logic Board LED Descriptions

DIAGNOSTIC LEDS

LED LED Color
Battery Green If lit, batteries have been installed correctly and are
Present (Fig. 13) charging or have been fully charged.
Open Limit Green If lit, the device senses a triggered normally open limit
(Fig. 11) switch.
Close Limit Green If lit, the device senses a triggered normally close limit
(Fig. 11) switch.
Mechanical Yellow If lit, the device is in a state where it will not release the
Release (Fig. 13) door.
Disabled
Annunciator Yellow If lit, 2.2k Ohm resistor is not installed on the annunciator
Open (Fig. 11) circuit. Note that LED lights when system is in alarm condition.
Detector Yellow If lit, 2.2k Ohm resistor is not installed on the smoke
Open (Fig. 11) detector circuit.
Ground Yellow If lit, a short to earth ground exists.
Fault (Fig. 12)
Annunciator Red If lit, the annunciator circuit is short-circuited.
Short (Fig. 11)
Line Power Red If lit, the line power is connected and switched "on."
Present (Fig. 13)
Detector Red If lit, the smoke detector circuit is short-circuited.
Short (Fig. 11)
T R O U B L E S H O O T I N G
Annunciator Open (Yellow)
Annunciator Short (Red)
Open Limit (Green)
Close Limit (Green)
Description
Figure 12 - Power Supply Board LED Descriptions
Action Required
If the LED does not come back on after installing the
batteries, check battery connections are as illustrated.
If door is on the Open limit, input is connected properly. If
door is not on the Open limit, check that auxiliary limit
connections are made as illustrated.
If door is on the Close limit, input is connected properly. If
door is not on the Close limit, check that auxiliary limit
connections are made as illustrated.
This is caused by being in close limit or by sensing an
electric door operator. Check limit switch connections and
motor operator control voltage connections.
Check that the annunciator is installed as described in
Wiring Instructions.
Check that a 2.2k Ohm resistor is connected in the circuit
as illustrated.
Check that release device and all ancillary devices/loops
(detectors, annunciators, etc.) are grounded properly.
Check that the annunciator is installed as described in
Wiring Instructions.
If the LED does not light when power is applied, check
that the power is connected to L1 and L2 as described in
Wiring Instructions.
Check that the smoke detectors are connected in the
circuit as illustrated. Press the "Reset" button to reset the
detectors.
13
Ground Fault
(Yellow)
Power
(Red)