Avionics Training

3 Replies

Avionics Training

Posted by Byron Deen on Aug 6, 2017 1:08 pm

Quick question: Can we use a 12 Volt external supply source on a 24Volt Electrical System just for the purpose of powering Avionics to train on the ground?? Thanks Piper PA 32 (New to Me with updated panel)
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Re: Avionics Training

Posted by Lonzo Mc Laughlin on Aug 7, 2017 6:34 am

No, it won't work and if anything might harm your 24 volt system.  See if you can borrow a 24V system from a FBO or hanger buddy.

they aren't terribly expensive.  Perhaps a couple of you can share the cost of one.


Re: Avionics Training

Posted by Mark Mitchell on Aug 7, 2017 2:56 pm

You can also buy a 24v 20amp commercial power supply for around $75, plus cabling to the aircraft. I did this on my old plane and it worked well. I can't remember where I found the information as to what specific type of supply you need. But know it can be done easily.

Re: Avionics Training

Posted by David Welch on Apr 19, 2018 1:49 am

Read the POH regarding external powersources.  Most Cessna's external power plug will ONLY charge the battery, and NOT power the avionics bus.   In my 182P, once power is applied externally a relay trips to route power to the battery.  When the avionics bus is on, flips the relay back to the battery as the source. You think your're runninng avionics off the external power, but just draining the battery.  

Furthermore, take great care in the external powersource that's plugged into the external power connector.  NEVER use car chargers/minders intended for lead acid batteries with aircraft gel cell batteries.  

Check your POH and wiring diagram.  It can be done pretty easily, but consult with someone who knows your plane.