![background image](http://html.mh-extra.com/html/aeroqual/series-300/series-300_user-manual_2862858039.webp)
High gas level alarm
WARNING
Failure to insert a circuit protection diode, shown as above, will
result in damage to the monitor if a voltage spike is created by
the relay.
Wiring for control
The control pin can be wired to supply control of a gas
concentration between upper and lower concentration limits. The
upper and lower limits can be set by the user, thus affording the
user the opportunity to customise the control. The factory default
settings are dependent on the gas sensor head selected at time
of purchase.
To switch to GND use pins 3 and 6. For a 12V output wire to pins
3 and 1 (see following diagram for typical wiring). This feature will
only operate while powered by the AC adaptor.
Control is achieved by using a software latch. If power is lost to
the monitor, the switch will open and therefore turn off the exter-
nal device connected to the monitor external output. The
following wiring diagram demonstrates the typical wiring to
achieve the required control.
1
2
3
4
5
6
RJ12
12V COIL
MINIATURE RELAY
AC RELAY
BELL ETC
BELL SUPPLY
+12V Nom. -from Plugpack
150mA max