SMS SenTRI, Data And Installation Instructions, Page: 28 / 52

Metal back box
A metal back box must be used for base or semi-flush mounting.
The earth continuity must be maintained throughout the whole
loop. The earth must be securely connected to the back box.
In - Out wiring to SenTRI bases
Programmable input/output
All SenTRII devices can be configured as either monitored input
or unmonitored output. The factory setting of the programmable
input / output is unmonitored output, to drive an external repeat
LED without a series resistor.
There is a maximum cable length limit of 15 metres from the
SenTRI base to the external I/O Unit.
The input can accept signals such as fire, non fire or fault, these
are configured during commissioning. As a fire input it is possible
to connect a conventional Manual Call Point (non UK application
only) with a series resistor of value 470 Ohms coupled with an
end-of-line 10Kohms resistor. In this case the fire input is fully
monitored for open or short circuit faults.
The input can be setup as a non-fire or fault input using a similar
arrangement with series and parallel resistors as shown. It is
possible for such an input to trigger a command that is
configured to action an output elsewhere in the system to control
plant equipment such as the ventilation system.
Installation instructions
28
LOOP CABLE
STANDARD 60mm METAL BACK BOX
CABLE GLAND
LOOP CABLE
S-QUAD BASE CEILING TILE
2 SCREWS TO SECURE
BASE TO METAL BACK BOX
CROSS SECTION
OF CEILING TILE
EM2
OUT5
IN4
C3
EM2
OUT5
IN4
C3
L1
0V
L2
L1
0V
L2
EM2
OUT5
IN4
C3
L1
0V
L2
+
-
+
-
Unmonitored LED output
+
-
Remote LED unit
13449-01
+ - + -
+ - + -
EM2
OUT5
IN4
C3
L1
0V
L2
470
W
10
K
W
Input