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Voltage Regulator - Ducati to John Deere (non-RV)

Hi guys!

I'm the owner of a 2007 Sky Arrow E-LSA with a ROTAX 912ULS.

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My wife and I live in Mineral Bluff, GA and the plane is based at Copperhill, TN (1A3).

I was led to this site when I Google searched for info on the wiring to a Ducati voltage regulator.

After 10 years and about 450 hours, I'm on my third Ducati, though I'm not 100% sure the first two were bad. Often, the problem of the GEN light staying on could be traced to a bad or burned connection on the multi-pin connector.

Most recently:

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A Google image search turned up at least one similar image in this forum.

Cleaning up the connection got things working again, but I'm considering the switch to the John Deere voltage regulator. I would like to ditch the multi-pin connector and just go with individual spade connectors for simplicity.

My main question concerns the 6 conductors on the Ducati vs the 5 on the John Deere.

Ducati:

30497844391_5b10b4137e_z.jpg


My understanding is...

1) The case serves as the ground.

2) "Giallo" = yellow, and is the unregulated output of the generator

3) "Lamp" is for my GEN light

4) "Chiave" = key, so probably switched voltage from my Master switch.

My question concerns the "Rosso" = red and the "Batt", and where they would hook to the John Deere:

419%2BZCWA0fL.jpg


I think its clear the "Giallo's" go to "AC", "Lamp" goes to "Indicator Light" and the "Chiave" goes to "Ignition Switch". So where do the "Rossi" and "Batt" go? Might they both go to the "B+"? My AMM is no help.

I apologize if this has been covered, maybe repeatedly, but I really want to be sure not to blow anything up if I decide to make the change.

As an aside, has anyone come up with a setup to test the Ducati's?

Thanks in advance and I hope I can contribute in the future.
 
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I can't speak for how your plane is wired, but in the RV-12 the R and B terminals are both connected to the battery positive terminal. I don't know if that's the case in all installations or not; the RV-12 is the only one I've seen that uses the Rotax and the Ducati regulator.

I'm sure there is a wiring diagram for your Sky Arrow somewhere, that would tell you for sure. Also... burnt terminals like the ones in your picture are usually the result of loose connectors. You may want to gently crimp the female connectors, or replace them if they're too far gone. They need to be be tight on the spade lug.
 
There has been lots of discussion on the VansAirforce RV-12 forum about the John Deere Rectifier/Regulator. A search came up with THESE results.
The R and B terminals are connected together inside of the Ducati case. Therefore, splice the aircraft R and B wires together and connect them to the John Deere B+ terminal. All of your assumptions about wire connections are correct.
TESTING The Ducati regulator.
The John Deere "Ignition Switch" terminal must be connected to a switch and NOT directly to the main power bus or to the battery contactor or to the B+ terminal. If not switched, the pilot will not be able to shut off the alternator in the event of smoke in the cockpit, even if the aircraft battery is disconnected.
Individual spade connectors are a good idea because the connections can be tested individually for tightness. If the connections are not tight, they will get hot and cause damage.
 
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Thank you, thank you, thank you!

My main question was answered with that cutaway, showing the "Rossi" and "Batt" connected inside the Ducati case.

As delivered, the Ducati voltage regulator was deep in a tunnel with no airflow and nearly impossible to access. As soon as my plane was Experimental, I relocated it higher, in the airstream and much easier to reach:

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My engine is mounted "backwards", so the air flow is right to left in the above image. It's mounted on rubber-lined adel clamps, but I ran grounding wires from both ends to engine grounds. They're the two paired wired shown towards the left. I don't recall the gauge, but all 4 added together add up to a fair amount, though I'm considering going to a braided motorcycle ground cable when I do the swap, and will use conductive paste where it meets the regulator. Would the white heat-conducting paste used on the plugs be appropriate?

Finally, I found two similar looking "John Deere" regulators on Amazon.

One for $32.99 https://www.amazon.com/Rectifier-Re...&sr=8-1&keywords=john+deere+voltage+regulator

One for $23.10 https://www.amazon.com/DB-Electrica...&sr=8-8&keywords=john+deere+voltage+regulator

Is there anything that would favor one over the other, or is there another source I should consider?

Thanks again.
 
Would the white heat-conducting paste used on the plugs be appropriate?
Yes, perfect.
Is there anything that would favor one over the other
Yes, the price. LOL At that price, you could even carry a spare.
They are probably all made in China, even the ones sold by John Deere dealers. In fact, a RV-12 owner purchased one from a John Deere dealer and said that it looked exactly like the one he had previously purchased from the internet.
 
The Faston Rotax uses looks like a TE Connect PN 42281-2. The TE Connect data sheet does not "limit" the design current through the part, but does "recommend" not exceeding 15 amps continuous use on this part.
Perhaps that explains why there are two parallel connection points for the DC output of the Ducati regulator.
 
Thanks for all the input and advice.

I just ordered the John Deere from Amazon. When I get around to installing it I'll update this thread with a pirep.
 
After our EAA meeting today a friend was ready to help me with the conversion. It helps that he came highly recommended as very detail-oriented and professional.

Some issues were readily apparent. First, some of the crimps left a lot to be desired, and at least some strands were loosening and/or breaking:

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Once removed from the multi-pin connector, some of the terminals had definitely seen better days:

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Fresh terminals, sans connector, in place:

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The John Deere in place and wired up:

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We both then held our breaths as we started her up.

Eureka!

GEN light out and normal voltage readings:

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Note: the Sky Arrow voltmeter has always read about a volt high (1). I tend to trust the bus voltage shown on the Garmin (2).

Anyway, it was late and we were both tired. I'm going to try to get up tomorrow and make sure everything checks out in flight.

Thanks again for the help and I hope this little report may help someone out as well.

PS - Now we just have to get a small "Power by John Deere" decal!

PPS - Is it standard practice to log this change in the Engine or the Airframe logbook or both?
 
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PPS - Is it standard practice to log this change in the Engine or the Airframe logbook or both?

Typically, the airframe logbook. Remember that the JD regulator charges ar a higher rate than the Ducati so if you have a high voltage alarm limit set, you may need to bump that up a little. I did on my -12.

Glad you get your issue resolved. Keep us updated on how it goes over time.
 
Got to the hangar and made a short flight yesterday.

Voltage readings (engine off):

Battery (Aerovoltz lithium iron) with Master Off: 13.25v
Battery with Master On: 13.11v
Garmin: 12.7v
Panel 12v outlet: 12.97v
Panel voltmeter: about 13.8v (a little parallax error in photo below)

Engine off:

32252397142_b4d3a80e48_z.jpg



Went flying, and with just the strobes and landing light on, saw the voltage gradually go from about 13.7v to 14v where it seemed to level off:

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This is I think about .3v higher than the Ducati. Note the panel mounted voltmeter is consistently showing about 1v high.

I was a little surprised at the high resting voltage - I'm used to seeing about 12.7v on most lead-acid batteries. But the Aerovoltz data sheet says that higher voltage is typical, and the 14v charging rate is in the acceptable range:

32252399662_462bc2db30_z.jpg


Anyway, so far, so good. If anything changes, I'll report back.
 
Be advised . .

Got to the hangar and made a short flight yesterday.

Voltage readings (engine off):

Battery (Aerovoltz lithium iron) with Master Off: 13.25v
Battery with Master On: 13.11v

Ed, EarthX has documented an AC content limit of the charging power and the PM alternator/VR does NOT meet that specification.

You might do some research on that since you have a LiFeP battery. And/Or be sure your battery is in a sealed metal container with an external vent in case of a "thermal event" . AeroVoltz will not be special in this regard. Be safe up there.
 
Ed, EarthX has documented an AC content limit of the charging power and the PM alternator/VR does NOT meet that specification.

You might do some research on that since you have a LiFeP battery. And/Or be sure your battery is in a sealed metal container with an external vent in case of a "thermal event" . AeroVoltz will not be special in this regard. Be safe up there.

Thanks, Bill.

Can you maybe provide a link to what the issues are?

Here's my installation in the nose of the plane:

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(the photo is to remind me of the orientation of the terminals, which is opposite from stock)

I'm just using the bracket from the original lead-acid battery with a block below the Aerovoltz to take up the slack. Would not be too hard to fabricate a battery box to enclose it, if that was really necessary.

Just curious, do most builders/owners enclose their lithium-iron batteries? If so, is there a source for the enclosures or do you have to roll your own?
 
Thought I'd provide an update:

About 15 hours flown over the last 8 months or so.

The John Deere voltage regulator in my Sky Arrow has worked perfectly over that time frame, cranking out almost exactly 14v as indicated by my Garmin.

Thanks again for all the help, and yes - I definitely need to fly more!
 
Thought I'd provide an update:

About 15 hours flown over the last 8 months or so.

The John Deere voltage regulator in my Sky Arrow has worked perfectly over that time frame, cranking out almost exactly 14v as indicated by my Garmin.

Thanks again for all the help, and yes - I definitely need to fly more!

What's the part number for the JD regulator you're using?
 
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