LT0186 Issue 2.80
27 July 2012
Page 8 of 10
3.6 Connecting T-GEN using the DEF- Output
The following wiring is recommended for when the T-GEN is mounted in or adjacent to a fire panel that supports the
DEF- signal. Using the DEF- output disables the T-GEN fault relay, and therefore the quiescent current is 17mA lower
per T-GEN compared with using the fault relay. But the DEF- line is not supervised for open circuit. Note that link Lk7 on
the T-GEN(s) must be fitted in the DEF- position.
The power supply for the T-GEN must be supplied from a monitored 24V supply.
T-GEN
Master
+24V
+24V
0V
0V
ALM -
SIG
DEF-
T-GEN
Slave
+24V
+24V
0V
0V
SIG
DEF
-
+V
NO
C
BELLS
–
Resistors removed,
(Note 4)
EXT DEF -
Notes:
1.
Sigma 5, FP1600/OMEGA 64 Mk3 - EOL=10k.
Enable ALM- input monitoring on T-GEN - (MON
switch ON).
2.
Requires connection to a monitored 24V supply.
3.
FP1600/Omega64 Mk3 boards have three 7-
segment displays.
4.
Sigma 5 and FP1600/OMEGA Mk3 require resistors
to be removed. Remove R15, R16 for Sigma. Remove
R62, R63 for FP1600/OMEGA 64 Mk3.
0V
(see Note 2)
EOL
(see Note 1)
Sigma 5
FP1600 Mk3 (Note 3)
OMEGA 64 Mk3 (Note 3)
0V
3.7 Earth Connection
The T-GEN must be connected to the cabinet EARTH using either the EARTH terminal on the T-GEN PCB (located
beside the 100V Line Output) or by using a metal standoff on the bottom left hand mounting hole (an M4 washer and
nut are supplied).
3.8 Power Connection
WARNING:
Each T-GEN 50 draws approximately 10A for 20 ms when first powered up. Any fuse between the T-GEN
50 and its power supply must be a slow blow type rated 3A minimum (per T-GEN 50). Any switch contact
used to supply power to a T-GEN 50 must also be rated at 10A minimum (per T-GEN 50).
The T-GEN 50 presents a significant capacitance (6600
μ
F) on its power terminals, hence the high inrush current. This
capacitance can also invalidate the battery connection tests (that lower the charger voltage to see if the battery is still
present) on some power supplies (e.g. 1948 PSU) if the T-GEN 50 is the only device powered by the PSU. In this case
it may be necessary to add a power resistor to the PSU output to provide extra standing load. For the 1948 24V PSU a
820 ohm 5W resistor is typically required. Note the 33mA this resistor draws needs to be included in any battery
capacity calculations.
