One of the largest distributors of IR aircraft alternators is Plane Power, and they have a dismal record of reliability. Quite a few polls and threads on VAF discussing the problems with PP and auto installs. IR alternators, one wire alt’s, have a big ease of installation advantage, but there is little doubt the failure rates of PP and other automotive alternator installations is unacceptably high for whatever reason. People like ‘easy’ and cheap which is why most folks install auto 1 wire units, because the data speaks for itself on reliability.
Yep I heard that. Hartzell bought PP I recall. BUT PP issues does NOT = IR are bad.. PP issues are their own. They use external voltage regulator don't they? Or do they have internal regulators or both? Yes Both... From my 2 min research (Plane Power reviews on Aircraft Spruce), PP did not have over voltage *OV* on their internally regulator models. Regardless of model there were complaints of them. They stopped working, for things like stator or bearing failed after 18mo or 3 years. Yeah that is not great. May be they fixed that issue. I recall they have OV crow bar protection built in. I did notice in my 2 min research I see PP takes cores at $200. They also have expanded their STC and aircraft spacific alternator types, like case mounted gear driven Continental alternators, not just belt drive. Experimental market is just part of their current business. Looking at the "stars" there was some 5/5 and a few 4/5 on the certified side, and in the case of experimental 3/5. I would be mad too if my $1500 alternator kit stopped making juice after 18 months.
Not sure what the definition of dismal record is, a few post on VAF. B&C has had some issues as well. Not bashing either company. A few complaints is not a reason for me to jump to conclusions. To my point supply chain issues and QC comment above. Not going to argue PP's reputation. I'm not here to defend or bash any product. I am talking about SENSE wires on automotive alternators, and the topic of OV with internal regulators, frankly over hyped. Modern good ND Internal VR are not inherently prone to failure or OV. That is my story and sticking to it. Ha ha. PP is not know for OV with internal regulator is my takeaway as well, but they claim to have some crow bar built-in. The failures on Spruce Aircraft reviews bothers me. I suppose they have warranty. So do rebuilds from Auto Parts store, some "life time" warranty with towing expense and up to $250 in other expenses. Ha ha. So there is that. Typical warranty is 3 yrs. Most "experts" say alternators should last 10 yars. Assuming an alternator on a Lycoming in your RV has a harsher environment, 5 yrs? If you have a cheap auto parts store alternator you can afford to swap it out every 3 years.
I would not buy PP or B&C due to cost, not due to good/bad/indifferent reputation. As expensive as building a plane is, what is another $1000-$1500 I guess. But don't expect $$$$ to equal better reliability necessarily. The other reason I would not go with PP units for me personally, they are medium frame ND models, 60 Amps. I have a small frame ND that is 35/40 amps. That is all I need, thanks to LED's. B&C has always made a small frame 40 amp model, a nice product, wired for external regulator. All good stuff. PP vs B&C is not the topic I was discussing.
Bottom line you can't point to PP and say see IR alternators are bad. Besides my exhaustive 2 min research, I don't know all PP past issues were , but IR (internal regulator) was not the main problem, as far as I know, definitely not OV. I use off the shelf and DYI IR alternators, so no dog in fight.
We have to look at builders, how they install, operate and condition of their engine (prop vibration**). You can't get around the fact the alternator and rectifier, regardless of brand or where the voltage regulator is BOLTED to the hot shaking engine.
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All these companies are buying some or may be most components off the shelf. I know B&C is not winding their own rotor or stator, casting their own housing, making bearings. They buy them. B&C wires up their own VR and they are very simple, through hole board mounted with a handful off components, no IC.. I know B&C promoted at one time they take the stock rotor and balance it. Nice. I am sure the vibrating** engine their alternator is bolted to, regardless rotor balance, is putting in more vibrations** on the alternator rotor, than the stock rotor is making by rotating, with or without special balancing. I could be wrong, and it may be value added. You can't get around the fact the alternator is bolted to engine. It is driven by belt that helps a little.
Besides the IR, the rectifier is always onboard the alternator, regardless of where your voltage regulator is mounted.
Most or all know this, but for those who may not or for a review, a "rectifier" is inside the alternator housing, typically on the stator assembly; it is a separate component from the external voltage regulator (VR) or internal VR. It takes AC and turns it into DC. Regardless the rectifier has diodes and gets hot and shook with alternator regardless of what kind of VR you have, internal or external. These "semi conductors" are rugged and can take a beating in vibration and high temperatures. The rectifier however is a common failure point. Builders should minimize vibration** keep them cool from external heat as much as possible.
The VR and rectifier are not the only things that can fail. You have brushes, bearings, windings, stator, rotor. I had a belt fail once, yes belt. It's amazing they are as reliable as they are. I have had several Japanese cars I drove 20 yrs and +200K miles, and their ND alternators worked without fail or over voltage. We have focused on the inside or outside VR debate. We lost track of the fact alternator have many moving parts, other components.
They all can fail. Regardless of having the VR inside or out, they are fairly reliable. The voltage regulator even internally mounted is NOT the most stressed item (but try to keep it cool).
Builders who maintain their alternators, periodically removing them, disassembling them, inspecting brushes and bearings will enjoy higher reliability regardless of make model or VR location. You don't inspect and maintain the alternator, expect it to fail at some point. The alternators on planes are in a harsh environment, but we can help lower heat and vibrations**. We treat them like they are in a car. Go until they fail. More proactive maintenance, inspections, pays dividends.
** Balance your prop. It will save you maintenance, add reliability to everything, make the plane more enjoyable to fly. Not every technician is good at prop balancing. It is a bit of an art, and experience really counts. I had one guy balance my prop and it was no better, may be worse. Same plane, I went to a guy who balanced helicopter blades, as well as propellers of all kinds,, on fixed wing engines from Cubs to King Airs.. Night and day difference. I assisted him and he was thorough. Old school dude, knew his stuff. It was like a new plane. When engines are busting the airbox, baffles, oil cooler mounts it's vibrations.
