Installation instructions, Instrument set up, Important information and initial check out – Electronics International VA-1A User Manual

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Installation Instructions

D. Read the entire Installation Instructions and resolve any issues you may have before starting the installa-

tion. This may eliminate any delays once the installation is started.

E. Check that the instrument make and model marked on the side of the instrument and on the invoice are

correct before starting the installation. The S-50 Shunt is marked "100MV" and "100 AMP". The S-300
Shunt is marked "50MV" and "300 AMP."

F. Before starting the installation make sure the unit will fit in the location you intend to install it without

obstructing the operation of any controls.

G. If this instrument is to replace an existing unit in the aircraft, it is the installer's responsibility to move or

replace any existing instruments or components in accordance with FAA approved methods and proce-
dures.

2. Instrument Set Up:

On the back of the VA-1A is a hole allowing access to a small switch. The switch furthest to the right in this
window sets the VA-1A for a 12 or 24 volt system. The other switches have no affect on the operation of the
VA-1A. If you have a 12-volt system set this switch down. If you have a 24-volt system set this switch up.

Switch Access Hole

Switch Up = 24V.
Switch Down = 12V

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VA-1A

Back Panel

Internal Shunt (VA-1A
only)

3. Determine how the VA Unit will be installed in your aircraft’s electrical system:

Obtain an electrical diagram of your aircraft’s alternator/starter system from the service manual. There are
two common ways an ammeter is installed in an aircraft. One method is with the ammeter in the generator or
alternator lead. The other method is with the ammeter in the battery lead. The VA-1A or VA-1A-XX may
be installed using either method. The advantages and disadvantages of each method are listed below.

1. Important Information and Initial Check Out:

Installation Method

Advantages

Disadvantages

Battery Lead:

1. Shows load current on the

ground (engine off) and durring

an alternator failure.

2. All Warning Lights are
operational.

1. Cannot show load current durring

flight or when the engine is running.

Alternator Lead:

1. Shows load current durring

flight or when the engine is
running.

2. All Warning Lights are
operational.

1. Cannot show load current when

the engine is off or durring

analternator failure.