Interesting VR failure
Posted: Thu Sep 21, 2023 1:11 am
by Bryan Cotton
We had a new VR from Sonex. Voltage was edging up and we had seen 13.6 early in the flight. We were doing a night flight to an airport 26nm away. About the time we started descending, my hard wired red LED headlamp started going bonkers. Checked the voltage and it was over 15. Adam thinks he saw 18 before the display changed. The battery light fault came on. So we headed home. Voltage was variable, between 13.4 and 14.1 or so. Battery fault light went away on the ground, but voltage was only 13.2.
I’m going to try my Amazon VR and see what it does.
Re: Interesting VR failure
Posted: Thu Sep 21, 2023 10:15 am
by daleandee
What you are seeing my not be a failure of the regulator. I had a similar condition and when replacing the regulator I found a poor connection that I had missed earlier.
My Corvair uses a PM alternator. The same type regulator used on the Corvair & Jabiru engines may also work for the VW conversions:
Wires are as follows:
blue wires (2) are AC voltage from the PMA
the red wire (1) is charging voltage to the battery
black wire (1) is ground
yellow wire (1) is the sense wire & turns on the regulator
green wire (1) idiot light - generally not used
Pretty sure I’m not telling you anything you don’t already know. I’ve bought cheap reagulators and didn’t get what I paid for so spend the money for a good one. My plane is electricity dependant so I take a lot of care to be certain my electrical system works well all the time.
These kinda things can be frustrating …
Dale
3.0 Corvair/Tailwheel
Re: Interesting VR failure
Posted: Thu Sep 21, 2023 11:11 am
by Bryan Cotton
Dale,
What regulator is that? Do you have a part number and source?
Edit: one thing I’m considering is adding a dedicated ground. Currently the VR gets its ground through the firewall.
Information about PMG static winding failure
Posted: Thu Sep 21, 2023 11:50 am
by GordonTurner
I wrote to Bryan in a different thread and suggested that per the BandC Technical Manual for their AVC-1 rectifier/regulator, it mentions that the voltage may have to be increased to maintain wet lead acid or LITHIUM type batteries. It comes pre-set for Odyssey.
Also interesting was that BandC do not recommend their AVC-1 for use with Jabiru motors. This sparked my curiosity, as their statement was “may cause overheating of stator windings”. I did a little further digging, on the Jabiru website, and found this:
https://jabiru.net.au/wp-content/upload … edures.pdf
I believe that actually any installation using a PMG generator is susceptible to this problem. In summary, if the charge on the battery is very low, the PMG will burn itself up trying to match the current inrush to the battery when full power is applied. PMG’s do NOT govern current, current is a function of energy going into the PMG (engine rpm is a simplified way to look at it) and DEMAND.
So. Example. Generator rating is 20amps. Try to keep it at 80% or less most of the time for long life. So 16amps. Controlled by what electrical loads the pilot selects, and available based on rpm. Depending on the installation, the PMG may be able to provide significantly more at takeoff/climb power should the load be very high. In the case of a depleted battery, any battery but specifically a LITHIUM battery, its initial charging current demand could be much higher than 20amps.
Newer Jabirus have OVER-CURRENT protection specifically to guard against this case.
Presumably Rotax does too, hence they are the prime market for AVC-1.
Everything else leaves it UP TO THE PILOT to control the load. The only control is don’t take off with a deeply discharged battery.
The AVC-1 is not alone in this limitation btw. All of the VR’s out there that I am aware of do not provide OVER-CURRENT protection. So operate accordingly.
Good luck out there. Gordon
Re: Interesting VR failure
Posted: Thu Sep 21, 2023 11:53 am
by jaflint
The VR Dale is referring to is a Yanmar 129150-77712. Available at seafarerstore.com.
Re: Interesting VR failure
Posted: Thu Sep 21, 2023 12:18 pm
by daleandee
jaflint wrote:The VR Dale is referring to is a Yanmar 129150-77712. Available at seafarerstore.com.
That appears to be an even better unit! The one I found was on ebay under the John Deere name:
https://www.ebay.com/itm/354602415740
Buy a genuine JD or Yanmar regulator made in Japan (not China) as these work well. I’ve bought cheaper and was disappointed …
Dale
3.0 Corvair/Tailwheel
Re: Interesting VR failure
Posted: Thu Sep 21, 2023 11:26 pm
by Bryan Cotton
I find it curious that I had two voltage regulator failures in a row. One that has been good for 145 hours, and one that was brand new from Sonex. So, I’m going to investigate the potential ground issue. I put the old “failed” VR back in, and added a 10ga ground wire.
VR ground wire.png (446.03 KiB) Viewed 31993 times
The other end goes to my grounding point on the engine.
VR ground on block.png (546.42 KiB) Viewed 31993 times
My neighbors were spared a ground run at 10:00 tonight because it’s pouring out. I’ll report back tomorrow.
Re: Interesting VR failure
Posted: Fri Sep 22, 2023 3:31 am
by Skippydiesel
I have always been a big promoter of dedicated earth returns for all 12V systems.
This does not mean that the airframe can not be part /parallel in the circuit, but does mean that you don’t rely on the airframe alone.
Simple reasoning: an airframe earth return much like car chassi return, is dependent on the electrical conductivity of multiple joins. These joins usually work well, when the aircraft is new, but add years of vibration, may be a bit of salty air and you may experience elevated resistance through to complete failure- run an earth wire and you will never have an earthing problem. Simple low cost solution, that seems to get a lot of experts, LAIM’s and such, a bit “hot under the collar”.
Re: Interesting VR failure
Posted: Fri Sep 22, 2023 10:50 am
by Bryan Cotton
I am also a fan of dedicated returns. This was one place I skipped it for some reason.
I did a test run with the original VR. It is still failed. Will try the Amazon VR next. I’ve ordered a John Deere VR from the ebay link.
Re: Interesting VR failure
Posted: Fri Sep 22, 2023 2:19 pm
by Bryan Cotton
On a thread here somewhere, a link was posted to a Stens 435-081 VR. Here it is again:
https://www.amazon.com/dp/B000G65X4Q
Looks like a chinesium copy of the transpo VR that came in my Aerovee kit. Bolt in replacement.
Transpo vs Stens VR.png (604.99 KiB) Viewed 31908 times
Ground run looks promising. Here is a pic of my MFD showing 14.5V in the bottom left corner at just under 3000 RPM. No electrical load except for recharging the battery.
Alpha screen VR ground run.png (515.28 KiB) Viewed 31908 times
I turned on everything and it went down to 13.9V, which still seems good.
Now the question is - do I trust it to fly 630nm to Elmira, NY next weekend?
Edit: for $27, I have a spare on order.
Re: Interesting VR failure
Posted: Sat Sep 23, 2023 11:02 am
by Bryan Cotton
1.0 this morning, voltage got to 13.6v. Going to try for a longer flight and see what I get. No battery warning light, which is a nice change
Re: Interesting VR failure
Posted: Sat Sep 23, 2023 1:48 pm
by Bryan Cotton
1.2 hours, rolls loops and immelmanns. Voltage got to 14.0.
Re: Interesting VR failure
Posted: Sat Sep 23, 2023 5:58 pm
by Bryan Cotton
Another 1.4 hours. Somewhere after an hour we got 14V again. It spends a long around 13.5V, probably recharging the battery.
Re: Interesting VR failure
Posted: Sat Sep 23, 2023 6:41 pm
by Area 51%
I had a very light electrical load on Chett.
It never took more than 15 minutes to show 14.3 or higher.
You might consider an amp meter to find your actual usage. Or turn everything except the ignition off after reaching altitude to see if the alternator is even capable of putting out the required power.
Re: Interesting VR failure
Posted: Sat Sep 23, 2023 7:14 pm
by Bryan Cotton
I always turn the ignition off above 1000’ and run on the magnetrons. With no electrical load on the ground, I got to 14.5 pretty quickly, as shown in the picture above.
Re: Interesting VR failure
Posted: Sun Sep 24, 2023 10:16 am
by Area 51%
Charging voltage isn’t necessarily the same as available battery voltage.
Take a well depleted battery or one with a bad cell, put it on a charger, and the voltage will show as whatever the charger is set for as an output. Typically well over 14v. Turn off the charger and the battery voltage will quickly revert back to it’s depleted voltage and lack of amp-hours.
Showing 14.5v with no load only demonstrates the VR is doing it’s job. Because it takes more than an hour to get to that point (or not at all) in flight would indicate either a weak charging system, or a higher draw than the system is designed for.
In either case, the charging system is working close to 100%.
Since these charging systems seemingly were designed and built by the same company that engineered the iceberg detection equipment on the Titanic, I would expect the lifespan of the alternator to be short.
.
Re: Interesting VR failure
Posted: Wed Sep 27, 2023 12:25 pm
by LarryEWaiex121
Bryan,
Thanks for the information. I’m going to add a dedicated ground as suggested. Can’t hurt.
I retired just under two years ago from selling Kubota and New Holland equipment.
I watched for years the struggles with Jabiru and their Kubota supplied regulators.
I looked up the regulator they were using and its off a 1983 year vintage tractor.
As it turns out, the issue with the Kubota regulators was the amount of energy being passed through the system compared to its application on a tractor with minimum output required.
The wires and connectors were literally melting off the unit.
I had one fry on my Waiex when it had the original Jab Gen 1 solid lifter engine.
I wish I had that one back. I’d install it in this Onex and make it a rocket ship!
Since 2016 I’ve been running the Camit 3300 and virtually all the issues that befell the Jabiru have been addressed on this engine. Other than a overheat issue on #3 that has been rectified, it’s been a tank for 525 hrs and climbing.
Well now, back to the electrical matter on the Onex. Thanks again for your insight. Every little bit helps. This little Onex is a real hoot! I’m too big for it but I’m dedicated to maximizing the potential of this plane so I can confidently let it go to someone and they get to experience success with a well sorted out aircraft.
Larry
Re: Interesting VR failure
Posted: Wed Sep 27, 2023 7:46 pm
by Bryan Cotton
daleandee wrote:W
yellow wire (1) is the sense wire & turns on the regulatorDale
3.0 Corvair/Tailwheel
Dale, where do you hook your yellow wire up? On the output of the master contactor?
Re: Interesting VR failure
Posted: Thu Sep 28, 2023 12:06 am
by daleandee
Bryan Cotton wrote:
daleandee wrote:W
yellow wire (1) is the sense wire & turns on the regulatorDale
3.0 Corvair/TailwheelDale, where do you hook your yellow wire up? On the output of the master contactor?
It could go there. Mine is wired to my two way master switch. 1st position on the master switch is ground for the master contactor, 2nd position powers the voltage regulator by energizing the yellow wire.
Here is a page from Mark Langford’s Corvair site where he explains the wiring (about 1/2 way down the page). On his regulator there are only five wires but it’s using a case ground instead of a dedicated wire. He’s using a different regulator so you can’t really follow the position of the wires:
http://www.n56ml.com/corvair/dynamo.html
Re: Interesting VR failure
Posted: Thu Sep 28, 2023 9:44 am
by Bryan Cotton
Thanks Dale!
Re: Interesting VR failure
Posted: Sun Oct 01, 2023 12:52 pm
by Bryan Cotton
daleandee wrote:The one I found was on ebay under the John Deere name:
https://www.ebay.com/itm/354602415740
Buy a genuine JD or Yanmar regulator made in Japan (not China) as these work well. I’ve bought cheaper and was disappointed …
Dale
3.0 Corvair/Tailwheel
So I bought the regulator at the eBay link. I’ve installed it. It was a bolt-in job as the mount spacing was the same as my original transpo regulator. I made some 3/16" aluminum spacers to keep it off the firewall. All the wires mated right up - the regulator has male spade connectors like the other regulators. I did have to add a wire to mate to the yellow wire.
John Deere regulator installed.png (525.72 KiB) Viewed 7637 times
So far I have one ground run. At 3000 RPM, I am getting 14.5V with all loads off, and then all loads on. Looks promising.
Thanks Dale!
Re: Interesting VR failure
Posted: Fri Dec 08, 2023 4:25 pm
by Bryan Cotton
I now have 30 hours on my John Deere VR. It is awesome! Gets up to 14.5-14.7 quickly in cruise.
Re: Interesting VR failure
Posted: Fri Dec 08, 2023 7:11 pm
by daleandee
Bryan Cotton wrote:I now have 30 hours on my John Deere VR. It is awesome! Gets up to 14.5-14.7 quickly in cruise.
Glad to hear it’s working well for you. Mine will generally run at 14.7-14.8 (MGL panel instrument reads slightly higher than a dedicated meter). Odyssey says my battery is really happy at that rate. 8~)
Re: Interesting VR failure
Posted: Sat Dec 09, 2023 1:12 am
by pilotyoung
Bryan,
Could you post what the different colored wires are for. I am guessing that the two blue ones go to the alternator, I know black is ground. And I am guessing that the red one being bigger goes to the battery. But what are the yellow and green? And if my guesses are wrong, please tell me.
Thanks.
Re: Interesting VR failure
Posted: Sat Dec 09, 2023 2:03 am
by daleandee
pilotyoung wrote:Bryan,
Could you post what the different colored wires are for. I am guessing that the two blue ones go to the alternator, I know black is ground. And I am guessing that the red one being bigger goes to the battery. But what are the yellow and green? And if my guesses are wrong, please tell me.
Thanks.
Answered earlier in thread: viewtopic.php?f=6&t=7412#p55978
If you go back and read this thread there are a lot of answers to the questions you will have.
Best,
Dale
3.0 Corvair/Tailwheel
Re: Interesting VR failure
Posted: Sat Dec 09, 2023 10:29 am
by Bryan Cotton
There is another good VR thread out there too. Here is where I added cooling to my JD VR.
viewtopic.php?f=6&t=5977&p=56207#p56142