I want to not have to be discretionary in my use of electricity and with the 914 having electric fuel pumps I reckon it might be smart to consider a 2nd alternator. I believe there is a blank up front on the crankcase for one.....I would like to hear from anyone who has first person experience with using one please? 

Thanks in anticipation.

Views: 104

Reply to This

Replies to This Discussion

Would it not be a lot simpler and cheaper to just have a dual battery system with the 2nd battery isolated from the primary battery so that in the event of an alternator or primary battery failure, you'll have reserve power until you can safely land?

John

N750A

I think the issue is more that the 914 only provides 8-14A of usable power for accessories and non-critical loads (from what I'm reading here). A second battery won't help with that if one is trying to pull 20A, which isn't hard these days.

Sorry if I'm misunderstanding the topic.

Sorry if I'm misunderstanding the topic.

I think I misunderstood the topic more than you! LOL!  However, it does seem the trend in modern avionics and lighting is that amp demands are going down what with LED's, etc.

John

Pitot heat usually pulls 10 amps.

Ouch.....Do you have a heated pitot John? If so, have you ever flown in cloud, or just a quick transit through a layer or two, and put it on for that?

It is the heat that pulls the amps, I believe all heated pitot tubes are about that. I haven't gotten to my wings yet, but there's always the chance of some ice anytime flying though a cloud below freezing. It doesn't take much to make a pitot tube inaccurate, I would not fly IFR without a heated pitot tube even if you are not intending to fly in icing. VFR only not an issue.

10 amps is a lot. Agreed re icing, never had to think about it too much, always had heated pitot, but 10 amps plus electric fuel pumps on the 914 doesn’t leave a lot spare, you’d be chewing into the battery for sure. I need to find a 914 owner who is flying, if anyone knows one…?

I'm a bit late to the party but here is my build with a 914.  Many things take less power than it would first appear.  For example a Trig radio requires a 5 amp breaker but only pull about 1/2 amp continuous.  The fuel pumps are listed below as well.  As you can see my build came up with some room to spare.  The tablet chargers are still a bit of a question on what they'll draw continuously.

18 amps availab
0.5
ACK 406/121.5 MHZ E-04 ELT Just a wild guess.
1
Trig ty 91 radio w/ harness .2A continuous 2A when transmitting
0.45
Trig tt22 transponder w/ harness
0.1
Trig tn72 gps position source
2
iLevil AP, just a guess, calls for a 3A breaker
0.2
GRT engine monitor
4.2
2 chargers for small tablets
0.5
2 small pc fans for cooling tablets, combined <1A
1 heater fan .3A (heater fan and cooling fans won't be run at same time)
1.5
Aero LED nav/strobe/pos
1.7
Aero LED landing light
2.1
12v Aux for phone charging etc
1.7
2 rotax fuel pumps page 14. 1.7A/ea if individual. 1.5A/ea if running both.
0
electric elevator trim tab 2A breaker on friends plane
0
electric flap actuator 5A breaker on friends plane
15.95

Hey Jasper,

That's a detailed list and I didn't know you'd posted it to this discussion, thanks for that. I'll go over it more thoroughly as I get to that part of the build, hopefully not too far away. I am gathering you have a single alternator only at this stage? 

RSS

New from Zenith:

Zenith Planes For Sale 
 

Classified listing for buying or selling your Zenith building or flying related stuff...


Custom Instrument Panels
for your Zenith
:

Custom instrument panels are now available directly from Zenith Aircraft Company exclusively for Zenith builders and owners. Pre-cut panel, Dynon and Garmin avionics, and more.


Zenith Homecoming Tee:


Zenair Floats


Flying On Your Own Wings:
A Complete Guide to Understanding Light Airplane Design, by Chris Heintz


Builder & Pilot Supplies:

Aircraft Insurance:

 
 

West Coast USA:

 
Pro Builder Assistance:

 

Transition training:

Lavion Aero

K&S Aviation Services

Aircraft Spruce & Specialty for all your building and pilot supplies!

How to videos from HomebuiltHELP.com

Developed specifically for Zenith builders (by a builder) these videos on DVD are a great help in building your own kit plane by providing practical hands-on construction information. Visit HomebuiltHelp.com for the latest DVD titles.

© 2024   Created by Zenith.Aero.   Powered by

Badges  |  Report an Issue  |  Terms of Service