Electronics International VA-1A Operating And Installation Instructions page 14

Installation Instructions
With the improvements made to the VA-1A there are few disadvantages using either method.
Although EI's test pilot has a slight preference for the alternator lead when using the VA-1A, ease
of installation should be the determining factor. In most cases installing the VA-1A is a simple
matter of replacing your existing unit and adding a few wires (see Wiring Diagram).
Following is a typical diagram of each installation. Determine how the VA-1A or External Shunt
will be installed in your aircraft.
Figure 1: VA-1A or External Shunt Installed in the Battery Lead
Batt.
To Starter
Note: The VA-1A or External Shunt should not be installed in series with the starting current.
To Voltage Regulator
Master Switch
Contactor
Starter Solenoid
This is the main lead going to the
Bus. It may come from the Master
Switch Contactor or the Starter
Solenoid.
3. Determine how the VA Unit will be installed
Alternator
F
B
This line may be connected currently
to the Master Switch Contactor or
the Starter Solenoid. In that case it
should be rerouted to the Bus or +
side of the Shunt.
-
VA-1A or External Shunt
10
G
+
B
U
S