Installation & Operation Manual Merlin 1500S
Rev: 1 01-21
6
4.
BMS OUTPUT
Connections are available on the board for Building Management Systems.
[NO Normally Open] [COM Common] [NC Normally Closed]
These are volt free connections.
This is a relay that changes state in alarm or when the gas is on/off and can be used in conjunction with
the 12V DC output and other external relays that affect other devices and controls such as purge fans
and audible alarms etc. See section; Switch Settings - for BMS options
5.
EM REMOTE
Connections for remote emergency shut-off or stop buttons is detailed on the circuit board as [EM
REMOTE]. This is linked out as a factory setting.
Remote emergency shut-off buttons should be volt free and wired to the Merlin 1500S using a plenum
security cable, white, 18/2 (18AWG 2 conductor), stranded, CMP or similar.
6.
GAS DETECTOR
Connections can be made for a Merlin gas detector (LPG, NG, CO
or Hydrogen).
If no detector is being used leave the factory fitted link in.
A wiring example is shown.
Refer to your gas detector manual for further information.
7.
FAN SWITCHES
This terminal switches when the key is turned on and off.
This can be connected to a fan switch (supplied separately) which can provide power to fans when the
control panel is switched on.
8.
CO2 MONITOR
This terminal can be used to connect a Merlin CO
2
monitor to shut off the system in the event of a high
concentration of CO
2
.
If no CO2 monitor is connected, the panel will ‘beep’ upon power up and the CO2 LED will flash 3 times
to indicate that this terminal has been disabled.An external power supply is required.
Refer to your CO
2
monitor manual for further information.
9.
12V DC
This is a power output for external auxiliary devices when there is power at the panel and can be used to
create a relay switch with the BMS relay output.
Max output: 50mA