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John Deere voltage regulator wiring...Help!

T

TomRV8

Active Member
Well, my Ducati regulator bit the dust. I purchased a John Deere regulator part number MIA881279 (I read here on the list this replaced part number AM101406).

The new regulator came yesterday, and there are absolutely no markings anywhere on the unit labeling the wires. No letters, words, symbols...nada...

Randy's post on 8/13 with pics was great, but my JD regulator is totally different than his. (maybe his is the AME101406?)

Has anyone used this unit? If so, can you help with the wiring please??

Here is a pic of the new unit. (The Ducati's wires are labeled G,G,R,B,L,C)



Any help would be greatly appreciated!

Thanks,
Tom
 
jd regulator

this is from Joe earlier this year.


Mich48041 Mich48041 is offline


Join Date: Apr 2008

Location: Riley TWP MI

Posts: 1,826





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Permanent magnet alternators (dynamos) do not have a field winding and thus no "F" terminal. The "C" terminal on the Ducati regulator serves a dual purpose: it is an on-off control and also bus-voltage sense. The regulator monitors the voltage on the small yellow wire that comes from the master switch. The Ducati regulator adjusts its output to maintain a system voltage of about 13.8 or so, at least on my plane.
The John Deere AM101406 and MIA881279 terminal "IGW" corresponds to the "C" terminal of the Ducati. I have not installed a John Deere regulator on my RV-12 because the Ducati has not failed . . . yet. But I did replace the regulator on my Simplicity lawn more with a John Deere and its output is 14.2 volts, which is higher than the Ducati. Most aircraft and automotive regulators are set at 14.2 volts.

__________________
Joe Gores
 
Thanks for the reply.

I had seen this post from Joe in my searches, but the problem is the MIA 88129 has NONE of the wires marked to determine which wire is the "IGW" or what any other wire might be...

Tom


Harvey rv12 said:
this is from Joe earlier this year.


Mich48041 Mich48041 is offline


Join Date: Apr 2008

Location: Riley TWP MI

Posts: 1,826





Default


Permanent magnet alternators (dynamos) do not have a field winding and thus no "F" terminal. The "C" terminal on the Ducati regulator serves a dual purpose: it is an on-off control and also bus-voltage sense. The regulator monitors the voltage on the small yellow wire that comes from the master switch. The Ducati regulator adjusts its output to maintain a system voltage of about 13.8 or so, at least on my plane.
The John Deere AM101406 and MIA881279 terminal "IGW" corresponds to the "C" terminal of the Ducati. I have not installed a John Deere regulator on my RV-12 because the Ducati has not failed . . . yet. But I did replace the regulator on my Simplicity lawn more with a John Deere and its output is 14.2 volts, which is higher than the Ducati. Most aircraft and automotive regulators are set at 14.2 volts.

__________________
Joe Gores
Click to expand...
 
Search the web for Voltage Regulator and you will get tons of pictures and wiring diagrams. Also, look at the wiring diagram from Van's to determine where all the wires go. I think you can eventually figure it out. The red, black, and blue wires are obvious. I suspect that the yellow wire is the "sense" wire from the alternator, that just leaves the green one.
 
Tom,
You might want to verify your purchase. I searched both of those part numbers pretty hard on Google and found lots and lots of pictures and none of them look like what is in your picture. All of the pictures that I found have 5-tabs as opposed to the 6-leads that yours has. All of the photos have an identification for what the 5-tabs are, as well. I would question the vendor you purchased it from.
If I were replacing my voltage regulator in my commercial mower, that one in your picture wouldn't work.
 
Lemmingman said:
Tom,
You might want to verify your purchase. I searched both of those part numbers pretty hard on Google and found lots and lots of pictures and none of them look like what is in your picture. All of the pictures that I found have 5-tabs as opposed to the 6-leads that yours has. All of the photos have an identification for what the 5-tabs are, as well. I would question the vendor you purchased it from.
If I were replacing my voltage regulator in my commercial mower, that one in your picture wouldn't work.
Click to expand...

Sure worth checking but I did the same search and found these:

https://www.google.com/search?q=MIA...ved=0CAcQ_AUoAmoVChMIxqih3JOHyQIVQaEaCh1-nAyT and https://www.mowerandtractorparts.co...70-f912-f915-mia881279.aspx?keyword=mia881279
 
Gil Brice gives the best advice:
I would question the vendor you purchased it from.
Click to expand...
Bomberger's has incomplete info.
Here is an educated guess:
The two blue wires connect to the dynamo.
The red wire is positive DC output.
The black wire connects to ground.
Now the problem is, what are the other two wires for?
Possibilities are:
Voltage sense input
Regulator ON-Off control
Indicator lamp
I do not want to guess the purpose of the yellow and green wires. If I remember right, way back when the RV-12 kit first came out, there was a wiring mistake that caused a couple of regulators to burn up. So it is better to verify where each wire goes for sure.
 
Thanks everyone for the replies!

I have done as much internet research as I can with my limited web smarts. Haven't had any luck thru John Deere, and a general Google search only shows one pic of the unit, and will try to contact that guy who is a Zenith owner that appears to have used the unit.

I bought the unit thru Amazon and am trying to contact the seller. I'm not expecting much help there though. Will try to contact my local dealer to see if they can assist.

Joe, I think you're probably right on the wiring, but don't want to take chances on the unknown wires unless it's my last resort...

I'm still hoping someone chimes in at some point that has already figured it out!! I'm running out of ideas :-(

Tom

Mich48041 said:
Gil Brice gives the best advice:
Bomberger's has incomplete info.
Here is an educated guess:
The two blue wires connect to the dynamo.
The red wire is positive DC output.
The black wire connects to ground.
Now the problem is, what are the other two wires for?
Possibilities are:
Voltage sense input
Regulator ON-Off control
Indicator lamp
I do not want to guess the purpose of the yellow and green wires. If I remember right, way back when the RV-12 kit first came out, there was a wiring mistake that caused a couple of regulators to burn up. So it is better to verify where each wire goes for sure.
Click to expand...
 
Tomkk - You stated your regulator which was located inside the cockpit at the new location has failed.

Has it always been located inside or was it firewall forward for a period of time prior to moving it inside to the new mounting location?
 
John-G said:
Tomkk - You stated your regulator which was located inside the cockpit at the new location has failed.

Has it always been located inside or was it firewall forward for a period of time prior to moving it inside to the new mounting location?
Click to expand...

It's been there from the beginning. I haven't seen any description of the VR failure mode others have experienced so I don't know if my failure is typical or not. The damage to the outer shell was me trying to get the connector out - the heat had fused connector to the shell in that area. I was surprised that I hadn't smelled any overheating odor.

oio.jpg
 
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Lose spade connector?

Wow! Interesting photo Tom ... almost appears as though there may have been a lose spade connector on that pin which build up a high resistance. That is unless that pin got really hot from within the regulator.
 
Please report to Vans

I really hope you put a detailed report into Van's on the failure. Might be a one off as everything electrical has risk of failure no matter how well designed/installed. I'm sure they are tracking performance of these regulators and used that data to recommend moving them to inside the cockpit when installing a second screen. If the long term failure rate "inside" the cockpit away from the engine heat is still leading to unacceptably high failure rates, they would be in the best position to detect that trend.
 
John-G said:
Wow! Interesting photo Tom ... almost appears as though there may have been a lose spade connector on that pin which build up a high resistance. That is unless that pin got really hot from within the regulator.
Click to expand...
That was one of my thoughts as well but, unfortunately, I couldn't tell because I couldn't get it apart without damaging the connector and pin. I know that I'd previously had an intermittent charging problem and found one of the pre-crimped pins loose on the wire with a bad crimp - I don't remember which wire it was. I suppose this might have been another one, don't know. I did cut the soft black backing out of the VR so I could see the circuit board underneath. The solder joints where the two "G" pins attached to the board were damaged (not a smooth flow of solder) but I don't know whether that was a manufacturing defect that caused the failure or the result of overheating caused by the failure.
 
That sure looks like a spade connection failure to me. John Peck had a similar failure a year or so ago and documented it on this site. When my Ducati regulator (then located forward of firewall on the shelf with cooling tube) failed a while back, it was, in my opinion, the result of internal solder joints letting go due to heat/vibration. There was no burning of the plug as shown in your picture. My replacement Ducati regulator is now located aft of the firewall per Van's recommendation -- all operating well so far.
 
TomRV8 said:
I'm still hoping someone chimes in at some point that has already figured it out!! I'm running out of ideas :-(

Tom
Click to expand...

After looking at a dozen wiring diagrams, I can make an educated guess. You need your provider to give you the terminal codes for each wire to be sure, but I'm about 90% sure on the following. The Green wire from the VR is not used. Most diagrams identify the Green wire as an indicator light. Connect the Blue wires to one each of the heavy Yellow wires in the harness. It doesn't matter which one to which one. Take one of heavy White wires from the harness and tie it off. I covered mine with shrink tubing. It's not needed. Connect the other heavy White wire from the harness to the Red wire on the VR. Connect the Black wire from the VR to a mounting bolt/screw. Connect the small Yellow wire in the harness to the small Yellow wire from the VR.

Caveat coming.......

This is my best guess. If you simply can't get a pin diagram from the vendor, I would give this a try, but don't get mad at me if it doesn't work. I deduced these connections based upon what I've seen as general industry standards for color coding the wires in the wiring diagrams. "Most" of the time, the Yellow wire is the sense and the Green wire is the indicator light. Since there are two blue wires, I assume those are the wires to the alternator (two Yellow ones). The Red and Black are relatively safe bets I'm thinking.

This is the best I could come up with after looking for about an hour. If that doesn't make you comfortable, I'd just go down to your local tractor store and get a different one that has the terminals marked properly and write off the first one to FleaBay.
 
Thanks!

I stopped by my local John Deere dealer yesterday and they were absolutely no help. That was just about my last hope... Then I get home last night and see the post below...

Randy to the rescue! Thank you Randy for spending the time to research and help me out. Great people on this list aren't there!

I take your caveat to heart, but from the few things I've determined so far, I believe you've got the rest of the wiring figured out.

I will get it installed this afternoon, and report back to the list. Hopefully it will work correctly and others will be able to benefit from the collective help I received from this forum...

Thanks again Randy!
Tom


f1rocket said:
After looking at a dozen wiring diagrams, I can make an educated guess. You need your provider to give you the terminal codes for each wire to be sure, but I'm about 90% sure on the following. The Green wire from the VR is not used. Most diagrams identify the Green wire as an indicator light. Connect the Blue wires to one each of the heavy Yellow wires in the harness. It doesn't matter which one to which one. Take one of heavy White wires from the harness and tie it off. I covered mine with shrink tubing. It's not needed. Connect the other heavy White wire from the harness to the Red wire on the VR. Connect the Black wire from the VR to a mounting bolt/screw. Connect the small Yellow wire in the harness to the small Yellow wire from the VR.

Caveat coming.......

This is my best guess. If you simply can't get a pin diagram from the vendor, I would give this a try, but don't get mad at me if it doesn't work. I deduced these connections based upon what I've seen as general industry standards for color coding the wires in the wiring diagrams. "Most" of the time, the Yellow wire is the sense and the Green wire is the indicator light. Since there are two blue wires, I assume those are the wires to the alternator (two Yellow ones). The Red and Black are relatively safe bets I'm thinking.

This is the best I could come up with after looking for about an hour. If that doesn't make you comfortable, I'd just go down to your local tractor store and get a different one that has the terminals marked properly and write off the first one to FleaBay.
Click to expand...
 
I agree with F1Rocket (Randy) about the RED, Black, and Blue wires. And he is probably right about the yellow wire too.
Today I experimented with the JohnDeere AM101406 voltage regulator on my lawn mower. The regulator is the type with male 1/4" spade terminals and they are labeled. I pulled off the IGN wire and connected the red lead of my voltmeter to it. Then I turned on the lawnmower ignition switch and probed the IGN and "L" terminals on the regulator with the voltmeter black lead. The voltage on the IGN terminal was 0.4 volts higher than on the "L" terminal.
IF the MIA881279 regulator has the same internal circuitry as the AM101406, then the voltage test described above could identify which wire (Yellow or Green) is to be connected to the ignition (RV-12 harness yellow).
 
You're welcome Tom and thanks Joe. That's good info. You might want to check this Tom. Couldn't hurt.
 
John-G said:
Wow! Interesting photo Tom ... almost appears as though there may have been a lose spade connector on that pin which build up a high resistance. That is unless that pin got really hot from within the regulator.
Click to expand...

My regulator connector looked very similar to this one when it failed. I determined without a doubt it was the result of my incomplete seating of the spade lug. I think it would be just about impossible to generate that much heat internally and transfer it out to the connector. So, I'm thinking we havent yet seen a classic regulator failure of a unit in the new location away from the engine heat sources. Which, if true, is good news to all of us who relocated our regulators.
 
A little naïve here… Why not buy exact replacement Rotax voltage regulator instead of substituting a different mfg with unknown wiring configuration? I see genuine voltage regulator for Rotax 912 on eBay at reasonable price.

Piper J3
120058 Flying
 
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Piper,

If you look through the blog you'll see that the Ducati VR has proved problematic. The John Deer VR is an experiment some owners have elected to try. VIVA EXPERIMENTA! 😀

Rich
 
MMiller said:
BigJohn, if I remember correctly you were having low voltage alarms and were troubleshooting your regulator in the days before the connector melted. A melted connector can be caused by a poorly seated pin, but I don?t think that was entirely the case in your failure. You had an older version regulator that is subject to an internal failure in the attachment of the power diodes to an insulated mounting plate. The regulator is a closed loop system, if the output is low (from those internal losses) it will attempt to draw more power from the AC input to compensate. This increased power draw may exceed the connector rating.
Click to expand...

Mike, you could be right. Anything possible I guess. As I recall, when I finally got my welded connector apart it was pretty clear that the spade lug was only partially seated. But, you are correct, I was having the classic symptoms of failure before I pulled it apart. Boy, you have a really good memory!
 
RFSchaller said:
Piper,

If you look through the blog you'll see that the Ducati VR has proved problematic. The John Deer VR is an experiment some owners have elected to try. VIVA EXPERIMENTA! 😀

Rich
Click to expand...

Piper, Rich is correct. The Original Rotax VR (made by Ducati) has been unreliable in service. Van's first tried to improve the life of the unit by running a blast tube from the air inlet to cool it. Failures continued, so then Van's moved it to the other side of the firewall, away from the engine heat. Some folks don't like the idea of having the VR inside the cabin space, and have come up with various other locations, and other regulators that are percieved to be of better quality. As Rich says, the beauty of experimental aviation. I haven't heard of any failures of the Ducati VR in its new mounting location until this one. That doesn't mean there haven't been any, just not reported here. Not everybody uses VAF. Of course, those of us who went to the time and trouble to move the VR "inside" are hoping for a good result!
 
OK, so I tried the John Deere VR today. My VR arrived a bit differently that tomrv8's - it had a connector attached like this https://www.google.com/search?q=joh...&q=john+deere+MIA881279&imgrc=OpTPiDL2UKuWQM:. Still unlabelled but did match the pattern of other JD VRs and that matched Randy's earlier guess.

Anyway, I connected

  • the two VR blue connections to the two yellows that go to the motor's dynamo,

  • the red VR connection to one of the whites that go to the AV-50001 Fuse and Switch module (tied off the other white wire),

  • the yellow VR connection to the small yellow wire going to the AV-50000 Control module.

Everything seemed normal when I started the engine: 2-3 amps & 13.8 volts. After the engine warmed up I ran it up. At full throttle it stabilized at 8 amps & 14.8 volts at which time I got a "Voltage" alert from Skyview.

So, I guess I don't know whether this is working correctly, just charging at a higher voltage than the Ducati, or whether there's a problem.

Any ideas?
 
!4.8 volts is pretty high. The Ducati regulator is set about 1 whole volt lower. Try doing the voltage test that I described in my post #20 above.
 
Mine runs at about 14.2. Was your battery discharged? Don't know if that might affect the charging rate. Because mine runs slightly higher than the Ducati, I did bump my limits to eliminate the nuisance alarms, but I think I set it at 14.5. FYI.
 
Thanks, Randy. No, I'd had my battery on an external charger so it was fully charged. I'm going to try to check the voltages Joe referred to this afternoon.

I haven't changed my limits from the default. Bottom of the Yellow is 14.3 and the bottom of the red is 14.6.
 
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8 amps at 14.8 sounds way too high to me. Admittedly not a battery expert, but I'm afraid this will overheat and eventually destoy your battery. You could research the specs on the installed battery to see what the tolerances are regarding maximum allowed charging voltage.
 
f1rocket said:
Mine runs at about 14.2. Was your battery discharged? Don't know if that might affect the charging rate. Because mine runs slightly higher than the Ducati, I did bump my limits to eliminate the nuisance alarms, but I think I set it at 14.5. FYI.
Click to expand...

Do you have one of these JD VRs installed? What wiring connections did you end up with?
 
The ammeter on the RV-12 measures battery current. If that 8 amps is positive, then the charging system is pumping 8 amps into an already fully charged battery. If true, then I think that without a battery, the voltage would go much higher. Maybe the voltage regulator is not regulating, but allowing the full capacity of the charging system to pass through to the aircraft electrical system.
 
Mich48041 said:
The ammeter on the RV-12 measures battery current. If that 8 amps is positive, then the charging system is pumping 8 amps into an already fully charged battery. If true, then I think that without a battery, the voltage would go much higher. Maybe the voltage regulator is not regulating, but allowing the full capacity of the charging system to pass through to the aircraft electrical system.
Click to expand...

Yeah, that could be the case. There was a huge difference between charging at idle (about 13.? v/1 - 2 A) and full throttle (14.8 v/8 A). Hard to tell but it it seemed relatively linear. Almost all was at idle while warming up and only a short time at the higher setting before I shut it down.
 
Randy, do you know the part number of the JD regulator you used that's working?

I took the measurements Joe suggested: the yellow VR wire had 11.52v and the green wire had .01v. I'm at a loss now. I borrowed a Ducati from a friend to rule out any airframe wiring issues and that worked perfectly. I guess I'll go back to the Ducati.
 
I took the measurements Joe suggested: the yellow VR wire had 11.52v and the green wire had .01v
Click to expand...
Was the ignition wire disconnected and used as a reference, or was ground used as a reference?
 
Mich48041 said:
Was the ignition wire disconnected and used as a reference, or was ground used as a reference?
Click to expand...

The ignition wire disconnected. Red VOM lead on the disconnected ignition wire and the other VOM lead to either the yellow or the green VR wire.
 
tomkk, your test results indicate that MIA881279 and AM101406 do not have identical internal circuitry. It is usually not a good idea to use trial and error to figure out how to connect electrical equipment. But without any documentation and since connecting the yellow wire results in high voltage, that leaves the green wire . . .
 
Many of the Regulator/Rectifier failures can be put down to placing the master switch OFF prior to shutting down the engine. To help prevent failure a Rotax p/n 966590 Capacitor ( 22000 MYF 25V ) should be fitted to the Regulator/Rectifier. I am surprised this is not supplied with the engine kit.
 
Someone w/ a Rotax in a different A/C was asking me about that. It's physically a really big capacitor. I don't think we have anything equivalent to that in our -12s, do we?
 
No further progress here but I contacted Odyssey about charging limits, desirable charging rates, etc. and and I thought I'd post the response here just for information.

"Thank you for contacting EnerSys/ODYSSEY. Charge voltage range printed on the battery is 14.4-14.8V at 77F or 25C. Most alternators put out 14.2V and at less than 14.0V, the alternator isn’t accomplishing any real charging. Optimum charging voltage is 14.7V and exceeding 15.0V can cause overheating, overcharging and lead to premature failure. No current limit required since the battery can take up to 5 times is Ah rating or about 80A for a PC680 in charge current when in good condition. Minimum recommended charging current is 6A. The battery will take what it wants based on need and availability."

Ignoring charging current since that appears largely irrelevant for this discussion, our Ducati's 13.8v is barely in the green (bottom of the RV-12's green is 13.7v), and well below the 14.7v optimum, and the optimum of 14.7v is in the red (bottom of the RV-12's red 14.6v and the top is 15v).

My 14.8v charge rate was clearly on the high side of what's allowed but now I'm wondering if my JD VR was wired correctly after all and just has a high charging voltage.
 
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According to the Odyssey Technical Manual, a discharged PC680 should be charged at 14.7 volts for 8 hours, then the voltage should be reduced to 13.6 for maintaining the battery. The Rotax engines in our RV-12 start so quickly, that the battery is not discharged very much. A question for Odyssey is, will it hurt the battery to have the voltage regulator set at 14.8 volts?
TomKK, my suggestion is to charge the battery, take the charger off, and wait at least 12 hours. Then measure the battery voltage before turning on the master switch. If the open circuit battery voltage is 12.8 or higher, the battery is fully charged. Then start the engine and run it up to full takeoff power. Shut off all unnecessary electrical loads. If the voltage goes above 14.8, then the John Deere regulator is not doing its job. Even if the regulator is working with a set point of 14.8, that is more than a half volt higher than necessary.
 
Thanks, Joe. I might try that just to reconfirm my original numbers but, as you alluded to, I'd never run it at the max allowed voltage - that's way too close to the 15v that definitely damages the battery. Unless I have a defective VR, I don't see the JD as an alternative. I think the NAPA alternative might be a viable alternative just based on Randy's experience in his earlier thread. I think that works at 14.2v and actually has the pins labelled :) I wish I'd seen that thread when I was researching it, don't know how I missed it.
 
Voltage Regulator or Battery?

I knew I shouldn?t have been following this thread?

I flew the plane twice today. This afternoon, as part of the before takeoff check, I noticed high charging current ? 8 amps. I didn?t think too much of it. Flight was short with one stop and engine restart.

Tonight I flew again but can?t recall what charging current was. Ten minutes into the flight I got a low voltage warning on the D-180 so I turned around and headed home. Buss voltage was showing about 11 volts and charging current was zero.

So my question is? did the voltage regulator go bad or did the battery die? I?m thinking maybe it?s the battery and that was causing high charging current earlier in the day.

Second question is what is model number for replacement Ducati VR? I see lots of Ducati VR?s on eBay.

Third question is what is PN for John Deere VR? Is there a direct replacement that doesn?t require wiring modification. Plug-n-play?

Thanks in advance?
 
The D-180 data log can be downloaded to a computer and analyzed with Excel.
Was the voltage high when the charging current was high?
Put a charger on the battery and charge it up. Take the charger off. Wait until the next day, then measure the battery voltage. It should be 12.5 to 13 volts. A load test on the battery is also a good idea.
Low voltage and zero charging current indicates a bad voltage regulator, regardless of the battery condition.
John Deere part numbers: AM101406, or MIA881279, or JDR1406
The John Deere regulator terminals are different than the Ducati. So not plug and play.
 
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