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13.0
Addressable Loop Interference on
Phone Handset Lines
Addressable loops can cause noise on the phone handsets connected to the FACP, especially
on handsets connected to System Sensor addressable modules. Mircom has several
recommendations for reducing this noise. Keep these recommendations in mind before you
start a job.
13.1
Use the Quad Loop Adder
Connect loops to the quad loop adder main board (ALCN-792MISO) instead of to loop 2 (the
loop that is hardwired on the Fire Alarm Control Panel). Each quad loop adder main board
supports 2 addressable loops.
Contact Mircom Technical Support for assistance:
Toll Free
1-888-647-3665 (North America Only)
Local
905-695-3535
13.2
Avoid Sources of Electrical Interference
Avoid running phone cables near sources of electrical interference or noise, such as:
•
Other cables, especially cables for addressable loops.
•
Motors (for example, fans and dampers).
•
Fluorescent lamps.
13.3
Use the TNC-5000 Telephone Bus Terminals
There are two ways that telephones can communicate:
•
Over the cables (either twisted pair or fiber optic) that connect the nodes to each other.
The nodes communicate over the ARCNet protocol (a protocol for communication
between computers). If you check
Digital Phone
in Job Details in the Configurator, then
the phones communicate over these wires. (See section 19.5 on page 134.)
•
Over the telephone bus terminals on the TNC-5000 (telephone network controller)
boards. If you uncheck
Digital Phone
in Job Details in the Configurator, then the phones
communicate over the telephone bus terminals.
To reduce interference, use the telephone bus terminals for telephone communication instead
of the ARCNet wires.
If you decide to use the ARCNet wiring for telephone communication, connect the telephone
bus terminals as well. If you experience too much interference on the phones over the
ARCNet wiring, you can easily switch to the telephone bus terminals instead.
13.4
Use Shielded Wiring
•
Use 18 gauge shielded twisted pair cables for the connections between TNC-5000
telephone bus terminals, and for the connections between the addressable modules.
