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timotb
10-20-2013, 02:33 PM
At present I'm using a shunt attached to engine sensor wires 24 and 25 to sense total alternator output. In the latest Vertical Power VPX Pro manual, Marc states in section 3.7:

"The EFIS displays a VP-X page which shows individual device current
as well as total current through the VP-X. The EFIS also has an ‘Amps’
gauge that is used to show the readings from the shunt. In some cases the
EFIS ‘Amps’ gauge can be used to display total system current from the
VP-X. Please check with your EFIS manufacturer for details."

How can the amp gauge be configured to show total system amps from the VPX?

Rob Hickman
10-21-2013, 09:10 AM
The Amps gauge will not display the VPX current. The VPX page in the EFIS will display the VPX current. The VPX does not know the actual current output of the Alternator.

rleffler
10-22-2013, 06:29 AM
I just noticed this attribute on my 4500s this weekend and was under the perception that the AMPs guage would also show the VPX amps.

Rob, is your recommendation is to install the AMP shunt as oppose to enabling (via future update) the EFIS to display the VPX current? I am also interested in understanding why one is perceived better than the other.

Rob Hickman
10-22-2013, 08:32 AM
The Shunt or Hall Sensor read the actual current from the Alternator. The VPX can only detect the current of the devices that are connected to it. The VPX does not measure the current being used to charge the aircraft battery or electronic ignition.