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One more bad Voltage Regulator

I have not replaced my Ducati regulator because it has not failed . . . yet.
But here is how I would do it:
Label each wire that connects to the Ducati rectifier/regulator with the
letters: G, G, R, +B, C. "L" is not used. Remove each fast-on terminal from
the plastic connector using a small flat screwdriver to release the spring latch.
The plastic connector is not used on the new regulator because the spacing
between terminals is different. Connect the fast-ons to the John Deere
AM101406 rectifier/regulator, matching the wire marker labels to the letters
on the rectifier/regulator. Notice that the big yellow wires (doesn't matter
which) go to "G" terminals. The small yellow wire goes to the "C" terminal.
Wires "R" and "+B" have previously been spliced together in Van's harness.
Only one of them is connected to the John Deere regulator. Insulate the
other one. The most challenging task is mounting the new regulator which
has different mounting hole spacing. After installation, check electrical
system voltage. It will probably be higher than what the Ducati regulator was
set at (less than 14 volts). If the voltage is higher than about 14.5, then I
would be concerned about over charging the battery. 14.2 VDC is good.

What is driving me to install it is the continual discharging I see at lower RPMs with everything running. I usually fly with the strobes and nav and landing light flashing in the busy terminal area - I have ADS-B and am planning on dual sky view eventually - and when on descent I do see a discharge occurring with everything running. I was doing touch and goes the other day and it drove me crazy seeing that yellow discharge on base/final/rollout every time.

I am curious to see if that fixes the problem without causing another one (like wrecking an expensive battery). Perhaps installing a temp strip before and after on the battery might help.
 
What is driving me to install it is the continual discharging I see at lower RPMs with everything running.

This is normal with a permanent magnet type alternator.
It does not operate like a traditional alternator, which can vary the field intensity based on the output of the alternator (such as when RPM gets low)
 
This is normal with a permanent magnet type alternator.
It does not operate like a traditional alternator, which can vary the field intensity based on the output of the alternator (such as when RPM gets low)

Do you think this Deere replacement will solve that issue with the higher voltage?

Or is it a waste of time?

Randy - what have you noticed since you installed yours? Does it still discharge at lower power settings?

I'm kind of worried about the electrical fire in the cockpit issue as well. There is nothing worse imho - especially if you cannot isolate the source and turn it off.

Too many have bit the dust because of this and we don't have smoke hoods and O2 full face masks in the RV-12 cockpit.
 
Randy - what have you noticed since you installed yours? Does it still discharge at lower power settings?

No. I was getting a few alarms because this VR charges at a slightly higher rate than the Ducati. I upped the alarm limits on the top of the Green, Yellow, and Red by .2 to give it a little more room. Everything seems to be working just fine now.

I'm kind of worried about the electrical fire in the cockpit issue as well. There is nothing worse imho - especially if you cannot isolate the source and turn it off.

I agree. Scott and I do not agree on a number of things and this is one of the major ones. Having been smoked out by the VR when it fried on the firewall side I can't imagine bringing it inside the cockpit.

I like the looks of the German replacement that is rated higher and look forward to finding a way to import some of them.
 
I agree with Scott that a permanent magnet alternator (dynamo) puts out less voltage at low RPM. Replacing the regulator will not help that. The regulator can not put out more than what comes in from the alternator. However, a voltage regulator with a higher set-point will help recharge the battery quicker when the engine is at a higher RPM. This might not be a concern for longer flights. But for a plane that flies mostly short local flights, a slightly higher charging voltage might be advantageous.
 
Ordering German regulator

Very nice work finding this regulator. This can be ordered and paid with Visa or MasterCard on the site. I translated the page using Google by right clicking on the page and choosing translate. Some good information about the known Ducati VR problems according to this vendor.
Toward the bottom of the page just above the "MADE IN GERMANY" OVAL click Order.
Translate that page or not it is also in English and USA is a destination in the selection.
Looks like 165.55 euros
Jerry
 
My German cousin is a Light Sport mechanic (after retiring from the German Navy as a Tornado pilot). I sent him the web page address and asked him for his read on it. I'll let you know what he thinks.
 
Very nice work finding this regulator. This can be ordered and paid with Visa or MasterCard on the site. I translated the page using Google by right clicking on the page and choosing translate. Some good information about the known Ducati VR problems according to this vendor.
Toward the bottom of the page just above the "MADE IN GERMANY" OVAL click Order.
Translate that page or not it is also in English and USA is a destination in the selection.
Looks like 165.55 euros
Jerry


I TALKED to them and they told me that they do not ship outside of the EU at this point. If you all email them and beg, they might see a market worth the effort to deal with customs for but, please, don't just assume anything because the website suggests you might be able to get it.
I have one on order through my parents in Germany and I will report when I got it.
As my Ducati is starting to flake out after engine start (~82 hrs. Hobbs), I will drop the SK regulator in as soon as I get it.
 
I TALKED to them and they told me that they do not ship outside of the EU at this point. If you all email them and beg, they might see a market worth the effort to deal with customs for but, please, don't just assume anything because the website suggests you might be able to get it.
I have one on order through my parents in Germany and I will report when I got it.
As my Ducati is starting to flake out after engine start (~82 hrs. Hobbs), I will drop the SK regulator in as soon as I get it.

Maybe you could smuggle these in for us?
 
A point of curiosity - -

This is normal with a permanent magnet type alternator.
It does not operate like a traditional alternator, which can vary the field intensity based on the output of the alternator (such as when RPM gets low)

Scott,
Any alternator has a voltage vs rpm output called V by F curve. The field controlled ones have a low rpm turn on limit too.

Question: Are you saying that the low turn on limit for the Rotax alternator is above the low idle speed by design? or that at the low idle speed that the power output is so low that it may result in an output so low as to draw on the battery power?
 
Scott,
Any alternator has a voltage vs rpm output called V by F curve. The field controlled ones have a low rpm turn on limit too.

Question: Are you saying that the low turn on limit for the Rotax alternator is above the low idle speed by design? or that at the low idle speed that the power output is so low that it may result in an output so low as to draw on the battery power?

I am not talking about a turn on point, I am talking about output vs RPM.
A conventional field controlled alternator is effected by this also, but it has more built in compensation than a permanent magnet dynamo type does.
We are not just talking about idle RPM.... on the RV-12, if all equipment is turned on, you will go into discharge mode on the battery at an RPM much higher than idle.
If the battery has been depleted by cranking for a start, and there is a lot of equipment turned on, the situation is even worse.
 
My German cousin got back to me. He said that his experience has been that the Ducati units are reliable unless mounted in a high temperature or vibration environment (sound familiar). His P92 has been in flight training service 15 years on the same regulator.

He says the Silent Hekti is a reliable unit, but there is no after sales support so if you have any issues you can't count on help.
 
My German cousin got back to me. He said that his experience has been that the Ducati units are reliable unless mounted in a high temperature or vibration environment (sound familiar). His P92 has been in flight training service 15 years on the same regulator.

He says the Silent Hekti is a reliable unit, but there is no after sales support so if you have any issues you can't count on help.

Like we have after sales support from Ducati/Rotax! :mad:
 
My regulator just went after 220 hrs but thanks to you all I removed it pealed the black stuff and found the offending connection. Re-soldered and back in service. One thing, ever sense I have been flying my 12 there has been a static or arcing sound in the head set after the fix no more static. The regulator had to be the source. They must not be cleaning the components prior to soldering.
 
So far, so good on my VR @ 350 hours. I've bought a replacement just in case. I have a question regarding the removal. The AN bolt head is so close to the VR body hat I am wondering how I'll ever get the bolts unscrewed. Frankly I can't remember how I tightened them. My plan is to replace them with machine screws if I have to replace the VR.

Is the bolt removal process a problem? My VR is on the "shelf" forward of the firewall.
 
Naive question

What exactly should I expect to see if/when volt. regulator fails so that I would know for sure its the regulator and not something else?
 
Some of began experiencing this symptom. You start up the plane for warmup but the voltage does not rise over the low 12V range. After the engine warms up, and you advance the throttle past about 3500RPM for the first time, for the ignition check, then the VR "kicks in" and when you go back to idle the voltage is in the 13s as normal.
 
Reviving the thread...

Now that alternate regulators have been installed for a while, are there any updates on installations, and performance?

The Silent Hektik is especially interesting as it is (almost) direct replacement and good quality. Any word on getting these in the U.S? I know at least one has been installed on the 12. Torsten's blog has a good write-up on installation issues but he hasn't updated lately.
 
Two weekends ago on a cross country I got a Low Voltage alarm after starting and my bus voltage was very slow to recover. I replaced my battery (3.5 years in PHX heat par for the course), but still had low bus voltage, so I swapped out the regulator. I now get a strong charging current of +7 amps at 4000 RPM after starting.

FYI I used a 100 amp load tester from Harbor Freight to baseline the new battery at 10.5V under load. The old battery tested at 10V under load.

Is there a bench test procedure for checking the old removed regulator?
 
Does anyone out there have bad regulator they would like to get rid of? I need one with a good connector as I want to use the connector on another project.
 
My John Deere regulator is going strong. I have a total of 190 hours on the airplane now with about 80 (I think) on the new regulator. I'm happy with my changes but would install one of Torsten's regulators if he'd just import a bunch and re-sell them.;)
 
Two weekends ago on a cross country I got a Low Voltage alarm after starting and my bus voltage was very slow to recover. I replaced my battery (3.5 years in PHX heat par for the course), but still had low bus voltage, so I swapped out the regulator. I now get a strong charging current of +7 amps at 4000 RPM after starting.

FYI I used a 100 amp load tester from Harbor Freight to baseline the new battery at 10.5V under load. The old battery tested at 10V under load.

Is there a bench test procedure for checking the old removed regulator?

Forgive me if you already provided this information in an earlier post, but I would like to know the mounting location of the failed VR. Original, original with blast tube, new location under the avionocs bay, or other.
 
After blowing a Ducati about every 150 hours I installed an aluminium heat shield plate between VR and exhaust pipe as well as I riveted additional plates to the VR to enlarge the cooling area.

The temperature strips I glued on showed about 20 deg F lower peak temperature and since this mod it survived 200 h.

I have all options installed as well as a second SV1000 screen and on all the time.
Recently also a camera is connected to the Dynon looking aft. Great.

I purchased a Silent Hektik which I carry as spare but it has not been out of the box.
 
For what it's worth

As we are back in the Voltage Regulator business, I want to report on the result of my tentative cure to this issue. If you don't remember, earlier in this thread I reported about relocating the VR inside the cooling tunnel. This is further documented in the sticky about Modifications:
http://www.vansairforce.com/community/showpost.php?p=969272&postcount=248
As I am in the middle of my annual, I took a look at the VR inside the cooling tunnel and was able to read the temperature strips I had put on the housing of the regulator (you can see one (red) strip on one picture in the link above). My inspection found that none of the temperatures was reached during the past summer (I flew for about 60 hours). It means that the temperature of my VR never reached 71 degree centigrades. I believe that if the cause of the failures of the Ducati Regulator is a combination of high temperatures and vibrations leading to the degradation of the solders connecting the SCRs, this relocation of the VR should result in fewer failures. Of course only time will tell.
 
more cooling options?

Probably I should refrain myself to post this undocumented comment, but I promise to complete the info once (if) I get it...

Last week while changing oil at the plane a pilot passed by and asked about the RV12 and the led's light, Dynon, etc. We spoke about loads and of course the regulator came into the conversation.

As it turns, he runs a printed circuit company that provides solutions to hi-tech organisations, and he seemed to be especialised on heat dissipation.

When I show him our Ducati reg, he said, "good enough for a bike, but not for this application", and immediately suggested three improvements:

1. Paint the fins of the regulator black.
2. Use the conductive compound all under the reg (and if possible also below the silicone).
3. Use a ratio of 4:1 in volume on the cavity that holds the airflow coming from the ram air.

He also suggested to get more of an inverted funnel cover, rather than the square we have, forcing air to get through all the fins, unlike the current flow that hits right on the middle.

He was on a rush and left me with all the theoretical explanations behind his black, and 4:1 ratios... but promised to come back...

Anyway, if you are despaired and have tried it all, now you have a new plan for this weekend...

Godo
 
Those are very good suggestions. Automotive radiators are painted black because that color gives off more heat. And heat conductive paste or film should also be used. Those are two things that can be done without a design change.
 
I understand the black body emitter issue, but unless you use a black sharpie I would be concerned that the paint layer might act as an insulator. It would seem that in the firewall location convection would far exceed any radiative cooling. Not sure if car radiators are black for the black body issue. I've never seen a painted oil cooler or air conditioner condensing unit.
 
And another one...

I started to hear noise in my headsets at low revs, and planned to investigate at the next service interval.

Then I started to get low voltage warnings prior to takeoff.

Then these also started to appear at idle throttle prior to landing.

On the last flight, the elevator trim wouldn't work until a few minutes after I was airborne.

These problems always disappeared after a few minutes, which is why I was procrastinating...

Today I replaced the VR and all of these problems have disappeared.

Cheers...Keith
 
Did you replace the voltage regulator with Rotax PN or did you substitute another brand? Did you install in same location under the cowling or move to "cooler" location?

Piper J3
 
I'm lazy. I replaced with like-for-like in the same location. I got five years use out of the first one. It and the step (another topic) have been the only failures over the period.

Cheers...Keith
 
That's what I'm planning to do if first reg lasts as long as yours did.

Big careful with Arctic blast of severe winter weather coming your way...

Piper J3
 
You can send another arctic blast if you like. The weather was cold but dry. Thick air, lots of lift, unlimited vis, ideal really. Especially when the heater is quite effective at cruise revs.

Cheers...Keith
 
I started to hear noise in my headsets at low revs, and planned to investigate at the next service interval.

Then I started to get low voltage warnings prior to takeoff.

Then these also started to appear at idle throttle prior to landing.

On the last flight, the elevator trim wouldn't work until a few minutes after I was airborne.

These problems always disappeared after a few minutes, which is why I was procrastinating...

Today I replaced the VR and all of these problems have disappeared.

Cheers...Keith

The typical Ducatti VR failure mode is that it does not turn positive amps as soon as the engine is running. This should be caught way before your takeoff. I think that the standard checklist from VANs includes this check (as well as oil pressure) right after engine start. Even if the amps becomes >0 after increasing RPMs it is likely that you have the typical Ducatti VR failure: a solder degraded that will reconnect with temperature increase. Eventually the solder will fail completely. To make this symptom more visible do not connect accessories, avionics and autopilot before you start the engine.
 
Graphical illustration of voltage

Yesterday I downloaded my Dynon stats onto my laptop. I have drawn graphs of rpm and voltage for the last flight before replacing the voltage regulator and then similar graphs for the first flight following replacement.

1zh1lvo.jpg


Here the voltage fluctuates at various power settings.

2j3nude.jpg


Here the regulator copes whenever the rpm is above idle.

Cheers...Keith
 
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RV-12 Voltage Regulator

Just had the second VR fail at about180 Hours. First failed out of the box.

What is the part number for the John Deer VR? It sure sounds like there is a quality control/design failure.
 
Vans RV12's seem have a high and disproportionate number of VR failures. We were just talking about this in class last month amongst some of the other instructors and IRC's. Most of us believe it has to be one of three things. Heat (#1 cause) from where it is mounted on the metal shelf just behind the #4 exhaust. I know there is an SB for relocation, but many haven't done this. The VR must have its own ground wire and just mounting it to the firewall is not good enough. Internal heat from either too much load or not enough. No other single aircraft MFG is having this number of failures. There has always been a failure or two, but usually on different aircraft, but the 12's are having a disproportionate number.
 
Just had the second VR fail at about180 Hours. First failed out of the box.

What is the part number for the John Deer VR? It sure sounds like there is a quality control/design failure.


http://www.amazon.com/DB-Electrical-AKH6004-Rectifier-Regulator/dp/B00MWOQWP4/ref=pd_sim_sbs_328_1?ie=UTF8&dpID=51D%2BZvRMFHL&dpSrc=sims&preST=_AC_UL320_SR320%2C320_&refRID=0RADZRDX7GJ7G5SEV5RM

There are a couple of good threads on here for install. I ended up doing the second method using the existing holes and fabricated a ground wire from the case to the engine as well.

Been running and charging much better than the ducati.
 
Yep, I have a 100 hours now on my JD and it continues to work flawlessly. Personally (and I have zero scientific data to support this) I think that the heat is killing it. That's why I surrounded mine with a shroud all the way around, not just to blow air on top of it. One of the existing threads has pictures of my installation.

Found it. THREAD
 
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Rotax/ Duccatti regulator rectifier to John Deere

I have been running a John Deere regulator rectifier for more than 600 hours on our Rotax 912S powered Rans S7. We used a clone AM101406, we did put a blast tube on it to keep it cool. About $30 delivered from Amizon (prime).

I charges better than the Duccatti with the voltage pinned on 14.3 volts about a half volt higher than the Duccatti which is more suitable for the recombinant gas valve regulated battery (odyssey likes this higher voltage for long life and full charge)
 
Regulator mount

I just mounted mine today, behind right cooling fan under Avionics panel, not fun to mount and wondered why?? After running all wires under panel and not up above... don't know about ground?? nothing was shown?? Did get a notice that wire from Solenoid to starter is incorrect because of hole sizes...I did drill mine out..so it was incorrect and will order correct one....
 
Today at 153 hrs. my interior mounted regulator failed. Thankfully, my buddy Skunkworks had a new one in stock. I have been thinking recently that I should be carrying a spare. Looks like I am going to be testing the John Deere unit out. This is my second RV12. The regulator on my first 12 was under the cowling and it lasted 250 hrs. We really can't depend on these units!
 
Regulator failure

Today after first flight I had no charging going on..parked aircraft and started investigating..alternator putting out 13 plus...but output from regulator is only 6 volts...ordered a new regulator ($175.00) plus shipping...and now challenging warrenty claim...if these Ducoti regulators are failing at high rate, why not find a better unit??? Should be a better link between Van's and Rotax also..since I struggled getting to someone who could order a new regulator...
 
Today after first flight I had no charging going on..parked aircraft and started investigating..alternator putting out 13 plus...but output from regulator is only 6 volts...ordered a new regulator ($175.00) plus shipping...and now challenging warrenty claim...if these Ducoti regulators are failing at high rate, why not find a better unit??? Should be a better link between Van's and Rotax also..since I struggled getting to someone who could order a new regulator...

When you say "first flight", do you mean first flight ever, or first flight of the day? If first flight ever perhaps the unit is defective out of the box, rather than failing in service. Can you clarify?
 
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