Installation Instructions
12
4. Install the External Shunt (External Shunt Unit Only, VA-1A-XX)
Note: If you are replacing an existing ammeter, the shunt may already be mounted in the aircraft.
If this is the case, you should have ordered a VA-1A-XX unit that matches your shunt.
The external shunt should be installed in an appropriate location that minimizes the routing of
main cables (refer to the wiring diagram in this manual appropriate for your installation). It
should also be mounted in a location where inadvertent damage cannot occur. If the shunt can be
accessed easily, it should be covered. When mounting the shunt, use self-locking or safety wired
nuts.
In some rare instances a shunt may be mounted in the negative battery lead to ground. The VA-1-
XX may be connected to this shunt and will work properly.
5. Route the Circular Connector
Starting from under the instrument panel, route the circular connector end of the wire harness up
to the instrument mounting location. (See the wiring diagram at the back of this section). Place
the circular connector about 8 inches back from the panel. Tie wrap the harness in place approxi-
mately 1 foot back from the circular connector. This will allow the harness to be flexible and
accommodate varying lengths in instrument wires. Be sure these wires do not obstruct the
Be sure these wires do not obstruct the
Be sure these wires do not obstruct the
Be sure these wires do not obstruct the
Be sure these wires do not obstruct the
freedom of travel of any controls.
freedom of travel of any controls.
freedom of travel of any controls.
freedom of travel of any controls.
freedom of travel of any controls.
6. Route the Power and Ground Wires
Route the red wire in the wire harness to the aircraft’s 12 or 24 volt main or emergency bus as
applicable via an independent circuit breaker (one to two amps). An alternate method would be to
route the red lead to the bus via a one amp in-line fuse. With this method a spare fuse should be
kept in the aircraft. See the Wiring Diagram at the back of this manual.
Route the black wire in the wire harness to a good ground . Tie wrap these wires so they do
Tie wrap these wires so they do
Tie wrap these wires so they do
Tie wrap these wires so they do
Tie wrap these wires so they do
not obstruct the freedom of travel of any controls.
not obstruct the freedom of travel of any controls.
not obstruct the freedom of travel of any controls.
not obstruct the freedom of travel of any controls.
not obstruct the freedom of travel of any controls.
7. Route the Backlight Wires
For a 12 Volt system connect the White/Brown to the 12 Volt bus. Connect the White/Red wire to
ground.
For a 24 Volt system connect the White/Red wire to the 24 Volt bus. Leave the White/Brown wire
open.
4. Install the External Shunt
