Ldm Communications; Receive Only Ldm-32Fs; Receive/Transmit Ldm-32F - Fire-Lite LDM-32F Instruction Manual

4. LDM Communications

Receive Only LDM-32Fs

For duplicate annunciation of system points, LDMs can be configured for
Receive Only annunciation. Receive Only LDMs must be set to the same
address as the LDM they duplicate, but are not fully supervisable. Receive
Only LDMs intercept information being transmitted to a Receive/Transmit
LDM so that this information can be duplicated at an intermediate display
location. When configured for Receive Only operation, LDMs cannot transmit
information to the host control panel. Remote Acknowledge, Silence, or Reset
cannot be performed. Control switches on Receive Only LDMs are for local
lamp test only. If a Receive/Transmit LDM is located at the end of the EIA-
485 bus, it will provide supervision of Receive Only LDMs located on the EIA-
485 bus between the Receive/Transmit LDM and the FACP.

Receive/Transmit LDM-32F

LDMs that are configured to serve as full-function annunciators can both
receive status information for annunciation as well as transmit commands to
the control panel through custom-wired point control switches. This allows the
LDM to initiate control panel switch functions from a remote location in
addition to displaying the status of the system. In order for wiring connecting
all Receive/Transmit LDMs to be supervised, the LDM-32F addressed as '01'
must be placed at the end of the EIA-485 loop farthest from the FACP. Only
address '01' is supervised.
Fire Alarm Control Panel
LDM-32F PN 50055:C 03/20/01
EIA-485 Circuit
Figure 20 LDM-32F Supervision
Receive Only LDM-32F
Set to Address X
LDM-32F LDM-E32F
Receive/Transmit LDM-32F
Set to Address X
LDM-32F LDM-E32F
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