21
Installation and Maintenance Manual
Federal Signal
www.fedsig.com
Wiring the Allegiant Light Bar
To make the power connections on a Discrete:
1. Ensure that the lines are adequately fused as shown in Table 5 Wire functions and
fuse requirements on page 15.
2. Attach the Black wire to the negative battery (–GND) terminal. See Table 5.
3. Attach each power line through a fuse rated on Figure 2 to the positive battery
(+BAT) terminal. If a switch is desired, attach the switch between the fuse and the
product.
To make the power connections on a Serial Interface:
1. Ensure that the lines are adequately fused as shown in Figure 2.
2. From the light bar, route the CAT5 control cable into the vehicle cab or trunk
near the eventual location of the Serial Interface Module. An input cable is also
provided with the Interface Module.
3. Route and connect the Black lead from the light bar to the vehicle battery’s
ground
(–GND) terminal.
4. Route and connect the Red lead from the light bar through a 40 A Maxi fuse at the
source, which is the positive battery terminal (+BAT).
Figure 2 Power and cable connections
Serial
Interface
Module
(+BAT) Power Line (Red)
(NEG-) Ground Power Line (Black)
J1 Connector
Black / White Wire
CAT5 Com.
Cable (Gray)
White Wire
24-Pin Harness
290A7447
+
–
12 Vdc
Vehicle
Battery
Fuse (1 A)
Fuse
40 A Max
Ignition
Passenger
Side
Driver
Side
NOTE: Powering multiple devices with a common control wire may cause one or
more devices to briefly remain functional after signal power is removed. For example,
due to the high input filter capacitance, a strobe supply can briefly supply the current
required to signal a light bar function to remain on. If necessary, use a relay to isolate
devices with large filter capacitors (Figure 2). All components/wires are user-supplied.
