12 volt output from EMS

[skysailor]

I am installing the EMS harness. I split the wires in the harness into two groups. One group of wires stays on the cold side of the firewall while the other goes through to the hot side. I have sorted out the fact there are a couple of RED wires and three YELLOW and gotten each to the appropriate group.

I will leave the 5 volt supply inside and split it for use in various position sensors (trim, flaps, canopy lock etc). My question is this...Does anyone know of a use for the 12 volt supply wound with the Fuel Flow One wires other than Fuel Flow? I have a Lycoming so I will only need one fuel flow transducer. I could easily split it inside as well before it goes to the FF transducer but I am not aware of any other items which require a 12 volt instrument feed. I believe it is low current so it is really only useful for sensors. Am I missing anything? Does anyone know a reason to split the 12 volt line?

 

[mmarien]

I split my +12V between two fuel flow transducers and my capacitive fuel level probe. One inside (level) and two outside (flow) the firewall.

I used the Princton fuel probe. It draws 0.02 amps.

http://www.aircraftspruce.ca/catalog/inpages/princefuelprobes.php

There is a list on page 7-12 of the Installation and Configuration manual of possible uses for the EMS pins 15 and 18 and their current limit.

 

[skysailor]

I forgot about the fuel probes. Looks like I will split both lines to a small supply bus with one for each voltage in case I need more. Thanks for the heads up!

 

[mmarien]

Just keep in mind the current limits.

It seems that as more of the probes/sensors go digital it will require more regulated 5V and 12V power supplies. I mentioned to VP-X that they should add a regulated source on one or more of the pins. I believe the only one they have currently is for the flaps or trim potentiometer. The other method would be to hard wire in a DC to DC converter like a lighter plug charger for your cell or computer. I believe they are a regulated source and would be easy to hard wire in.

How are the projects going?