Generator AMP Rating

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Generator AMP Rating

Post by 8209 »

If I wanted to replace my generator. What would be the highest AMP rating I could go up to?
Thanks for the help.
Brent
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Re: Generator AMP Rating

Post by 8474 »

This is what you want....I know it's on my wish list.
https://www.aircraftspruce.com/catalog/ ... -01321.php
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Re: Generator AMP Rating

Post by 6643 »

Yes, if output is what you're looking for, get an alternator. Any generator you get will not be contributing anything below about 1700 RPM regardless of it's capacity.
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Re: Generator AMP Rating

Post by 4004 »

If you want to stay with a generator ( and its limitations) you can go up to 35A with out much problem and $$, of course with commensurate regulator and system upgrade ( wiring, protection device, etc).
Seems that most discussions now look to Plane Power but there is and alternative that seems to be unknown in these later years and should be considered and probably at a good $$$ saving.
Check the "Resources" on the home page under STCs. Conversion to the "150 Cessna 0-200' configuration is already approved with an STC that can be purchased. It uses the reliable Ford alternator system that's been around for years. One can then assemble his own parts for the system, per the STC, and present to ones A&P for installation. Years go, Fred Lagno, STC holder, would provide and alternator at a very reasonable price. Most "junk yards" should have them. The Ford one is a "kissing cousin" to the automotive one but don't go there - the aviation one uses a different/stronger rectifier bridge that has "aviation' marked on it. The system will provide 50/60 amps.
Probably most of you who have the 0-200 conversion already have the alternator. The STC covers the C series.

Oh yeah, one should also consider that the system has overvoltage protection. A Zeftronics regulator provides that IIRC. I converted a Bonanza 50 amp generator system to a 60 amp alternator with the Zeftronics reg with a field approval many years ago.
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Re: Generator AMP Rating

Post by 2066 »

Yet another option that may be worth considering(?), the B & C "Alternator". This (photo) is the "12 Amp" that was installed on our 140 a number of years ago via field approval. It has performed flawlessly with dependable B & C quality built right in...and, continued airworthiness directions indicates it'll go to normal engine overhaul, so no "maintenance" except for the normal drive coupling check @ 500 hours. While not a true alternator (...a "dynamo"?), it provides clean power at lower RPMs and easily supports all avionics, now including ADS-B in/out + landing light (with LED bulb). There's also now available a 30 Amp model...believe it's STC'd for some installations. Both weigh in at slightly over 4 lbs.(!), so significant weight savings. Fellow member Tom Reddeck has flown behind an identical 12 Amp, also "field approved", on his 140 for years and echoes similar positives. FWIW. Mac
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Re: Generator AMP Rating

Post by 2066 »

Edd wrote: "...A Zeftronics regulator provides that..."
My past experience with the Zeftronics products and the service back-up has been excellent. In fact, I penned a short article for one of our newsletters "many" years ago with heading "The Next Best Things To an Alternator". That was to share my experience in just replacing the old "tractor" regulator with the Zeftronics unit on my then 20 Amp generator. It was almost surprising the difference it made in "earlier" online RPMs charging and the very steady ("noiseless") current. And, when a gremlin caused an issue with the regulator, the Zeftronics folks replaced it, immediately, with no questions asked. Yet another very good product IMO. (...and, incidentally, the above B & C package includes OV protection.) Mac
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Re: Generator AMP Rating

Post by 8209 »

Wow! Thanks guys for all of the information. Obviously $$$ are a concern. So, that being said if I put on a 35 AMP generator what else would I need to change out to protect my electrical system? Edd I know you mentioned regulator and wiring protection. What does that mean exactly.
Thanks
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Re: Generator AMP Rating

Post by 8474 »

Hi Brent,
I guess the first question is why do you want/need to increase the amperage? Have you installed some high draw items? Are you having difficulty maintaining a charged battery? You may be able to solve some of these problems by reducing the draw by replacing bulbs with LED's. I'm replacing my landing lights with LED's and was able to change from a 25 amp CB to a 7.5 amp.

If you really need to increase the output of the generator for what ever reason the only wire that needs to be able to handle the increase is the one to the main Buss bar ( usually would flow thru the Ammeter first if installed) After that your existing fuses/CB's protect the rest of the system and the existing wiring should already be of sufficient size for the load it is feeding.

Hope that helps
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Re: Generator AMP Rating

Post by 6643 »

The cost of the replacement generator, regulator, and circuit protection device is going to be significant compared to the cost of an alternator installation. You may also have to replace the ammeter, depending on its range. And, again, this will do nothing to improve your electrical system at engine speeds below about 1800 RPM, when the generator will go off line. So, if your problem is the landing light in the pattern, a bigger generator will not help. A used alternator from a Cessna 150 along with the correct regulator, and Fred Lagno's STC, would probably be the most cost effective route to take. The plane power setup saves you some weight, to boot. The B&C alternator scares me as the outer housing spins, plus I think it's only 12 amps, although it will produce current at idle, unlike the generator. (Mac: Isn't that thing supposed to be painted traffic-cone-orange?)
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Re: Generator AMP Rating

Post by 8474 »

I agree with John, do what you need to convert to an alternator. I think B&C now makes a 30 amp version but I also would not go that route as I would not be able to get that approved in Canada as it's not STC'd and also would be concerned about the external spinning design. I would hazard to guess that by the time you hunt down a used 150 alternator, find a regulator and associated bits, you will be close to the Plane Power price and have a new alternator with warranty. My 2 cents....
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