What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Surefly with Z14 (dual batt, dual alt)

maniago

Well Known Member
Ive gone thru most of the Surefly threads here and didnt specifically see any discussion on wiring an impulse Surefly + standard mag right side with the Z14 architecture to keep the battery/alternator redundancy to the Surefly. I know I can call the co (but its sunday) and I understand they want a hot side feed hence the qu, so just fishing for info to chew on.

Thanks for any help.
 
Surefly is about to release a backup power system to allow dual installations in certified aircraft. I would definitely give them a call.
 
I have this setup.
Maybe I’m missing something but I’ve just wired it directly to the main battery per the install manual. What extra redundancy are you looking for?
You can still close the cross feed and join the battery’s with the main alt offline giving your ignition (and both buses) access to both batteries.
Seems like a relatively secure and redundant setup.
Cheers
 
I have this setup.
Maybe I’m missing something but I’ve just wired it directly to the main battery per the install manual. What extra redundancy are you looking for?
You can still close the cross feed and join the battery’s with the main alt offline giving your ignition (and both buses) access to both batteries.
Seems like a relatively secure and redundant setup.
Cheers

Maybe I have to go back thru the circuitry logic since its been a number of years since I built that part, but my first thought was if the Surefly comes of A Batt direct and that battery goes flat, theres no power to close the A master contactor to get power back to the source side of the contactor. The cross feed contactor only connects the load side of both A and B master contactors.

Am I wrong?
 
To me Z14 is too complicated. Too many switches for configuration, but if that is what you have then I think the intent from looking at Z-27 or Z-28 is that the electronic ignition run from the Battery Bus. I see what you are getting at about if you loose your primary battery you will lose one ignition. I think you are correct.

I think there are other ways of doing it, but it really depends on how many of these cross-feed relays and control switches you have, and exactly how you wired up your setup. It would appear to me that you could put the electronic ignition on the Main Power Distribution Bus (Z-14 terminology). Then when you turn on the master it will have power and if you turn on all of the crossfeed stuff it will have power from the secondary battery. Now the problem with this if something goes wrong with a unit on your Main Power Distribution Bus you can't power it down like you might want to without losing your electronic ignition.

I have a dual alternator single battery configuration, Z-13 effectively. I went with only a single battery since if it is maintained and replaced at regular intervals then I think I can minimize the risk of battery failure. Some may not agree but in other threads at least some agree. Now if you follow that same approach your primary battery is unlikely to fail and leaving the electronic ignition on the primary battery as I believe Bob was suggesting might be the best call.
 
One option would be to wire the contactor on the Surefly side in the same manner as a crossfeed contactor, so its coil can be energised from the crossfeed side. However, I take the view that you already have redundancy for inflight failures through the use of a mag on the other side.
 
Back
Top