Installing the VSI-2
RED
BLACK
Fuse
Power
switch
Positive supply
(+12V from battery)
Negative supply
(airframe ground)
Suggested fuse rating:
1.0 A slow blow
To other instruments
Cannon D-9
connector
Static port
Connect static port
to suitable static line
on aircraft.
Note: leaving this port
unconnected may lead to
VSI errors as cabin
pressure chages due to
airflow or other factors
Installing the VSI-2 is quite simple.
Connect the supply terminals to your aircraft’s power supply (you need a dropping resistor or pre-
regulator for 24/28V systems).
Install suitable power supply protection if you have a supply that can contain large voltage
transients such as can be created by starter motors and solenoids.
Ensure that the supply voltage will not drop below 8V during operation as this may result in
incorrect VSI readings.
Connect the static port to a suitable static air pressure line. If you have a slow aircraft or an
aircraft were the internal cabin pressure does not change during flight and is equivalent to the
outside air pressure you may find that it is not required to connect a static port.
For installations in typical ultralight aircraft pods, be aware of possible pressure changes inside
the pod during flight caused by ram air or suction effects. This may lead to a false indication of
vertical speed. Often these effects are dependent on the current angle of attack of the airflow
around your pod. You will need to install a suitable static port in these cases.
