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Name this alternator

gacnik123

Well Known Member
Hope some fellow aviators can tell me some info about my alternator. It’s working fine, but I want to find out if it has over voltage protection. I didn’t build my plane and I believe vans sold these back in the day.

Make?
OV protected?
Anybody had issues?

Reason I ask is Uavionix said my AV 30 failed from a voltage surge. Nothing else failed and my standard voltmeter stayed stable at 14.4v. Plus the AV 30 specs claim max input 60v. I’m pretty sure I’d seen smoke with that.

3F08C13D-30CD-4B8F-8754-11F5F5C4A0B8.jpg
572D37F3-E838-480D-86A3-537FDE1A47A5.jpg

Hope you can help.

Thanks John
 
An AV30 was gonna fail soon regardless Looks great, highly unreliable. Been thru 3, uAvionics always had an excuse to avoid any warranty consideration.

Seems you always get what you pay for. Sometimes Less!

George
 
I'll name your alternator Bob.
Thanks for the heads up about Uavionix. Seems like they don't want to stand behind their product. A voltage surge wouldn't affect only one thing in your system.
 
Looks like the 30a Nippon Denso that was sold by Vans and commonly used back in the day, I've flown them on my RV-6 since 1999. It is externally regulated and doesn't have OV protection built-in. I have an OV protection module that pops the alternator breaker but that is separate from the alternator.

Common number for the alternator is 14184, application is 1979 Honda Civic CVCC, no air conditioning.
 
An AV30 was gonna fail soon regardless Looks great, highly unreliable. Been thru 3, uAvionics always had an excuse to avoid any warranty consideration.

Seems you always get what you pay for. Sometimes Less!

George

Had the same experience with them!! Probably gonna put my original VSI back in. This was my second AV30 since May 2020
 
Looks like the 30a Nippon Denso that was sold by Vans and commonly used back in the day, I've flown them on my RV-6 since 1999. It is externally regulated and doesn't have OV protection built-in. I have an OV protection module that pops the alternator breaker but that is separate from the alternator.

Common number for the alternator is 14184, application is 1979 Honda Civic CVCC, no air conditioning.

Hi Sam, does this zener diode location look correct??

61F78291-916E-4BF2-800B-C88AF8EE17DE.jpg

Seems like it isn’t really doing much going from the 12v alternator post to ground. I think this was a failed attempt at over voltage protection. Seems like it’d just get hot as heck but not trip a fuse or breaker! Thought maybe you had an original set of instructions from vans that came with your alternator.
Thanks

John
 
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The Zener diode is not OV protection

John,

Here is a paragraph from the document which came with my alternator 26 years ago, it describes the purpose of the zener diode.

35-amp-1.jpeg

Here is the full alternator document in pdf format for your files.

View attachment 35-amp-alternator.pdf

Back then, the over voltage protection was usually based on an article in Bob Nuckolls Aeroelectric Connection book and described as crowbar over voltage protection. As Sam described, it was a separate circuit between the alternator and the main bus. You probably have it, but just haven't found it yet. At least that's my guess.
 
I've never seen a diode in that location, it's not a "standard" part of the alternator installation. Pretty sure it wouldn't offer any voltage protection, but I don't know it's purpose. One of our electronics gurus may have some insight.
 
Here are the pages I used to build the crowbar OV protection a long time ago. You might have something like this buried in your wiring.

crowbar-1.jpg

crowbar-2.jpg
 
Spike protection isn't the same as over-voltage protection. Over-voltage is where the regulator loses control of the alternator which results in the alternator yielding voltage high enough to damage avionics. Spikes are very short (millisecond) impulses.

The OV protection on my plane is via a small "crowbar" module that senses OV within milliseconds and shorts the field wire to ground which trips the field breaker shutting down the alternator. This module may still be available from B&C Specialty Products.

Couldn't find it on B&C site, but found a reference to it off-shore. You might poke around to see if one of these devices is in your wiring.

https://aero3d.fr/fr/regulateur-de-tension/3339-ovm-bc-over-voltage-protection-module-ovm-14.html

ovm-bc-over-voltage-protection-module-ovm-14.jpg
 
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F826562D-EE38-4B2C-8C49-F2D0B4272073.jpg

Thank you Dave and thank you Sam! I appreciate the quick replies and will look again tomorrow. Above was the only paperwork I found in my files and I can’t ask the gent who built it because he passed.

Thanks again

John
 
John,

Here is a paragraph from the document which came with my alternator 26 years ago, it describes the purpose of the zener diode.

View attachment 42852

Here is the full alternator document in pdf format for your files.

View attachment 42853

Back then, the over voltage protection was usually based on an article in Bob Nuckolls Aeroelectric Connection book and described as crowbar over voltage protection. As Sam described, it was a separate circuit between the alternator and the main bus. You probably have it, but just haven't found it yet. At least that's my guess.

Just saw you have a monocoupe!! Love them.
 
View attachment 42857

Thank you Dave and thank you Sam! I appreciate the quick replies and will look again tomorrow. Above was the only paperwork I found in my files and I can’t ask the gent who built it because he passed.

Thanks again

John

Interesting. I think that pre-dates my 1999 RV-6, the little OV module I have was the hot setup back in the late '90's.
 
I’m looking for one like yours as we speak. Might have found another company that makes them!! Did you guys use the ex Bus by chance? That’s what mine has. I meant to say the picture I posted above wasn’t how mine is wired, it’s just all I found in my files. Don’t know why it was in there.


8A263230-3FE8-453E-9E5D-B33BD9120C97.jpg
 
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Alternator

As stated previously the pictured alternator was sold in Vans Accessory Catalog as 35 amp ES 14184 W/O Fan. Also sold in Vans Accessory Catalog were voltage regulators ES MS-150A and ES VR-1751. Vans did not offer over voltage device in the accessory catalog.

Autoparts stores still sell Lester # 14184 remanufactured externally regulated alternators but with the fan that was removed for Vans accessory. Honda Civic 1979 used this alternator.
 
Thank you Alan I appreciate the info. I was curious about the regulator. Hadn’t seen anything like them at Spruce or wag. I think I found an Over voltage setup through olsentechllc.com that should work. Super nice guy.

Thanks

John
 
B&C offer the LR3D regulator with built in over-voltage protection and that is what I am fitting with the same alternator as yours in my plane.

If there really was an over-voltage event with your alternator then that may imply that the regulator is faulty and you will be replacing it?
 
Very true Paul. I’m gonna try this crowbar set up for ease first, mainly because my regulator is buried in the tunnel by my feet. Doable but it won’t be fun. My electrical is accessed easy by my right arm. If I do continue to have problem I’m gonna switch to B/C.

EB64B6C3-63EE-477B-B2CB-876F61F535A9.jpg

This was reaching in with my phone and zoomed.

Thanks

John
 
As stated previously the pictured alternator was sold in Vans Accessory Catalog as 35 amp ES 14184 W/O Fan. Also sold in Vans Accessory Catalog were voltage regulators ES MS-150A and ES VR-1751. Vans did not offer over voltage device in the accessory catalog.

Autoparts stores still sell Lester # 14184 remanufactured externally regulated alternators but with the fan that was removed for Vans accessory. Honda Civic 1979 used this alternator.

I'm using the 14184 with the fan in place. It rotates "backwards" but I have a blast tube pointed at the diodes and never had overheating issues...except the the time I asked it to charge a fully depleted battery after a jump start, the little 35a alternator put out 49a and cooked the diodes....pilot error. Don't jump start a dead battery.

I've always used the VR166 regulator with this alternator. 1975 Ford LTD, available at nearly any auto parts emporium for way less than $30.
 
John, the voltage regulator in your picture (post #21) is the ES MS-150A as mentioned by Alan in Post #18. Also known as the Transpo M-150A. This is what I have been using since completing my RV6 in 1996.

The M-150A has a small screw on the back side which allows you to adjust the output voltage of the regulator. This unit was also frequently called the single wire voltage regulator.

I purchased one a couple of years ago:

https://www.motorcityreman.com/proe88vsjyad.html

VR-M150A.jpg

It was a direct mounting replacement. I had to change the connectors on the wires.
 
I’m going to order one to have an extra today!! Thanks to everyone for the part numbers and feedback. Also, the gentleman at the website I posted above, makes his over voltage setup like Sams, pictured previously, but adds a third wire with a button to test and see if the field breaker pops when it’s grounded. And, he’s an extremely nice guy and helpful. Just an FYI if anyone else reading this is interested.

Thanks all!!

John
 
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