SMS SenTRI2 - Device Loop Circuit Configuration

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Device loop circuits
Device loop circuits
Upto 4 loop circuits can each accept the connection of compatible addressable devices
/ outstations communicating on 3217 protocol. Where a maximum of up to 200 devices
/ outstations are allowed per loop circuit.
To maintain earth continuity on a loop, the loop cable screen must be continued
through each system device, whether the earth is connected to a device or not.
A loop circuit must not cover more than 10,000m
2
of oor area of a
protected site.
A spur circuit must always be taken from the ‘line common’ terminals
of a 3 ways device.
A spur must not cover more than the equivalent of one zone as
dened in BS 5839 Part 1.
As every loop device has an isolator tted, it is not necessary
to apply special attention where there are more than 32 devices.
However no more than a maximum of 512 devices shall be installed
on one control panel.
L2 02
Sounder Strobe/ VAD device
(2-way)
01 L1
L1 01 L2 02
02
L2
01
L1
L1 0V
Manual call point
L2 0V
PANEL
(2-way)
Earth to
metal box
Master Control Board
LOOP CIRCUIT 1
L1 0V L2 0V
LOOP n
IN4
OUT5
C3
SenTRI device
IN4
OUT5
C3
SenTRI device
Sounder Strobe/ VAD device