F3200/NDU AS4428.1 Installation Manual
Document No: LT0255
Applications
Page 6-20
5 July 2016
Issue 1.22
6.2.6
USING OLD ME0065
– ME0069 GAS CONTROL DOORS
Older F3200 gas panels were supplied with the ME0065-69 gas control doors (refer drawing
1931-47). These provide a 24V supply and switched 0V outputs to activate the
warning signs. They were designed for the original FP0628 AVI, but do support the Mk2
AVI. However, as wired these outputs are not suitable for supervising the wiring to the
warning signs, as is now required.
These gas control doors can be modified to common 0V, switched 24V outputs to enable
supervision of the warning signs. But in this case the original FP0628 AVIs cannot be used.
Two options exist for this
– replace the gas control door with the equivalent 2-wire version
(ME0438-ME0442), or modify it as shown in Drawing 1931-132 and in the steps as follows:
1.
Turn power to the panel off and physically isolate the actuating device (operate the
Gas Discharge Isolate switch). As a further precaution when working on gas
extinguishing systems, disconnect the actuator or remove it from the gas release
valve. Identify the thick black wire that runs from the Relay 1, 2 and 4 NO terminals
to 0V on the MAF/PSU. Disconnect it from the MAF/PSU 0V terminal and connect to
+VBF2 (or similar) instead. Place some red insulation tape around each end of the
insulation to indicate it is now a positive wire, not negative.
2.
Disconnect the two thick red wires that connect to the Sign+ screw terminal.
Discard the one that runs to the +24V screw terminal, and reconnect the one that
runs to the MAF/PSU to the +24V screw terminal.
3.
Run a thick black wire from the Sign+ screw terminal to 0V on the MAF/PSU.
4.
Re-label the following screw terminals:
Sign+
as
Sign-
Alert-
as
Alert+
Evac-
as
Evac+
SIO-
as
SIO+
5.
Run 3 wires to the Alert/Evac (Stage 1/Stage 2) sign(s) and 2 wires to the SIO sign.
Connect Sign- to COM, Alert+ to IN-T, Evac+ to In-B on the Alert/Evac signs.
Connect Sign- to com (or In-T) and SIO+ to In-B on System Inoperative Sign (set the
links to disable tones). Fit a 2k7 ELD from each of Alert+, Evac+, and SIO+, to
Sign- (0V) at the last AVI.
6.
Configure Relays 1, 2, 3, and 4 for supervision (fit Lk 1-4 to the S position) on the 8
Relay Board.
