Esser 8000C - Page 120

Page 120
Fire Alarm Computer 8000C / M
Connecting an external signalling device with loop monitoring
Monitored activation of external devices involves monitoring the loop for an end-of-line resistor of
10 k
Ω
. In the event of an incident, polarity changes between monitoring and activation voltage at
the (relay) connection terminals. The relay switches over from monitoring the loop to activating the
external device, such as a signalling device.
It is imperative to fit a protective diode (e.g. 1N4004 / 1A) in order to prevent the monitoring
current, for example, from activating external signalling devices while monitoring is in progress.
Example using relay K2 (terminal 5 and 6), monitored mode
☞
R = 10k
Ω
end-of-line resistor , V= protective diode (1A).
3
-relay module / 3-relay common trouble module
+
-
4
5
6
7
766231
alarm
V
R
+
-
+
-
4
5
6
7
766231
monitoring
V
R
+
-