Voltage Regulator Failed

[skippydiesel]

I seek your leaned advice;

 

At only 153 Hobbs hrs, my Rotax/Ducati Voltage Regulator seems to have "spat the dummy". This is despite mounting in cockpit (away from engine heat) extra careful grounding,  with dedicated fresh air supply. Now researching options - see below;

 

• Rotax/Ducati - Rotax PN 965349 / Ducati PN 362001. OM, poor reputation. About $350Au delivered

 

• CARMO CARR5115 MOSFET - local supplier "Vectriq Parts". Seem to have a strong following. Non standard Rotax connection. Claims of cooler operating and no need for 22000 Mu capacitor. About $300Au delivered.

 

• Silent Hektik DE - As yet no local supplier found. Confusing model descriptions. Confusing prices  $160 - 192Au in Germany. Fitted by at least one small aircraft manufacture. No reviews at this stage (see reading list below). 

 

• Electrosport ESR439 - Fitted to various motorcycles including Honda. About $300Au delivered. No aircraft related reviews.

 

• Advanced Voltage controller - Claimed to be specific aircraft VR. Estimated $570Au delivered. No reviews

 

• SHINDENGEN FH020AA  - Original fitted to various motorcycles. Look great. Prices vary from about $50 Au (copy?) to $500Au. No aircraft related reviews

 

• Mower style VR's eg suited to John Deere. 

 

Suggested reading, curtesy of "RV12 Build Log"

 

•  http://ctflier.com/topic/2371-regulator-rectifier-longish-and-techie/
•  http://www.dogaviation.com/2016/01/the-ducati-voltage-regulator-dilemma.html

[Red]

I have a spare SHINDENGEN FH020AA from one of my bikes, the input is 3 phase, not sure can this be used single phase with just the 2 wires from the 912 generator?

[skippydiesel]

8 minutes ago, Red said:

I have a spare SHINDENGEN FH020AA from one of my bikes, the input is 3 phase, not sure can this be used single phase with just the 2 wires from the 912 generator?

You are a gentleman sir. Thanks for the offer. At this early stage of the investigation, I am keeping my options open but tending towards the OM as is a known plug & play fitting. 

 

The CARMO also attractive (recently fitted one to a motorbike) but not keen on changing out the connectors,  as in a very tight spot.😈

[IBob]

Skippy, when you say 'extra careful grounding', presumably that includes the metal body of the regulator?
I ask because I'm aware of one that appeared to fail (it hadn't) because the body wasn't well grounded.

[skippydiesel]

1 hour ago, IBob said:

Skippy, when you say 'extra careful grounding', presumably that includes the metal body of the regulator?
I ask because I'm aware of one that appeared to fail (it hadn't) because the body wasn't well grounded.

I always go the "extra mile" to ground all of my 12V systems, so yes body & any designated terminals all back to battery Neg (-) not just to airframe.😈

[skippydiesel]

Come on all you Rotax jockeys - This is a common problem. Must be lots of experience/opinions out there.😈

 

[facthunter]

Regulating permanent magnet alternators is Magician's territory.  Nev

[IBob]

49 minutes ago, skippydiesel said:

Come on all you Rotax jockeys - This is a common problem. Must be lots of experience/opinions out there.😈

 

Is it a common problem, though???

Edited May 19 by IBob

[skippydiesel]

1 hour ago, IBob said:

Is it a common problem, though???

Yes - Rotax/Ducati rectifier/regulators have always been a weak point in the Rotax system. Check out the Rotax Owners Forum and you will find pages & pages, going back to the early day of the 912, on this topic.

 

In general the failures are put down to locating the unit in a high temperature and or vibration environment. Poor connections and/or earthing. However it seems that no matter what care is taken the service life can be from as little as under a 100 hrs to 500 hrs or so.

 

The above mentioned aftermarket VR's, particularly those that list Rotax as a compatible user, seem to be exploiting this weakness.

 

My problem is I don't seem to be able to find much in the way of product reviews, to assist in making a selection.😈

[IBob]

Curious. I asked because, thinking of the various Rotax powered aircraft at our airfield, I'm not aware of any having that failure.
No doubt there will be a limit to the design output: I see 13.5A quoted.
There is also a potential problem (no pun intended) with turning off the master switch with the engine still running, in which case the DC output spikes. Or that's my understanding, hence the fitting of the external capacitor, to take the edge off that. Will that damage the regulator, or is that principally to protect avionics etc?

[skippydiesel]

1 hour ago, IBob said:

Curious. I asked because, thinking of the various Rotax powered aircraft at our airfield, I'm not aware of any having that failure.
No doubt there will be a limit to the design output: I see 13.5A quoted.
There is also a potential problem (no pun intended) with turning off the master switch with the engine still running, in which case the DC output spikes. Or that's my understanding, hence the fitting of the external capacitor, to take the edge off that. Will that damage the regulator, or is that principally to protect avionics etc?

Check out Rotax Owner Forum - might take a day or two to read through the many pages of Rectifier issues.

 

My aircarft is fitted with an Earth X battery - 14V indicated is the norm.

 

Not the greatest understanding of electronics however my understanding of the 22000Mu capacitor, is to control/eliminate spikes which may interfere with other electronic systems on board, in particular the transceiver.

 

No idea why anyone would turn of the Master Switch, on a running engine, unless may be a suspected electrical fire/overheat.😈

[IBob]

28 minutes ago, skippydiesel said:

 

No idea why anyone would turn of the Master Switch, on a running engine, unless may be a suspected electrical fire/overheat.😈

Yep, it's a nono..........but can happen......

[Red]

They have a fair number of failures in UK use. 

i've had a couple of failures and know of others.

Guessing anecdotally something like 1 in 30 not lasting past a few hundred hours over here

[skippydiesel]

9 minutes ago, Red said:

They have a fair number of failures in UK use. 

i've had a couple of failures and know of others.

Guessing anecdotally something like 1 in 30 not lasting past a few hundred hours over here

As I say - check out the Rotax Owners Forum. I suggest a cold wet day, warm fire, comfy chair - it will take you forever to plough through all the threads on this topic.

 

Back to what I am hoping for - some experince /insight into the alternative VR's on the market.

 

Leaning towards the CARMO CARR5115 MOSFET  It being, available locally,  at the lower cost end, of the new breed of MOSFET type VR's & a plug/play without tricky voltage adjustments 😈

[skippydiesel]

Found another aftermarket offering -  https://www.aeroakku.com/REGULATORS/Schicke-Regulator-GR6b-OVP-12V::1901.html?language=en

 

Shicke GR6b-OVP is a compact AC rectifier-regulator useable for Rotax😈

Edited May 19 by skippydiesel

[Red]

Most over here either just buy another Rotax/Ducati or swap to the Carmo.

I havnt seen a Carmo Failure yet,  I know so far of one with about 300 hours on and all good time will tell

[skippydiesel]

1 hour ago, Red said:

Most over here either just buy another Rotax/Ducati or swap to the Carmo.

I havnt seen a Carmo Failure yet,  I know so far of one with about 300 hours on and all good time will tell

Thats good to hear😈

[dlegg]

Can an alternator be fitted to a Rotax? Changed to one on a Jabiru, no issues since.

[Underwood]

2 hours ago, dlegg said:

Can an alternator be fitted to a Rotax? Changed to one on a Jabiru, no issues since.

Well it has an alternator as standard (produces AC), but if you mean a car type alternator with a built in reg/rec then yes you can fit one.

[aro]

16 hours ago, skippydiesel said:

Back to what I am hoping for - some experince /insight into the alternative VR's on the market.

 

If the failures are being discussed on the Rotax forum, that's probably where you will find opinions on the alternatives. If there are few people here who have failures, no-one is likely to be able to make a comparison.

 

One thing I have heard is that high load isn't good for the Rotax regulators. One of the characteristics of the EarthX batteries is a high initial charging current, which seems like it might overload the regulator.

[facthunter]

I have a pile of Battery chargers and none of them are suitable for Lithium Batteries. Why would the standard Rotax voltage regulator just cope?   Nev

[skippydiesel]

36 minutes ago, aro said:

If the failures are being discussed on the Rotax forum, that's probably where you will find opinions on the alternatives. If there are few people here who have failures, no-one is likely to be able to make a comparison.

 

One thing I have heard is that high load isn't good for the Rotax regulators. One of the characteristics of the EarthX batteries is a high initial charging current, which seems like it might overload the regulator.

Thanks Aro - No one else has mentioned the high current/Earth X possibility.

 

All the more reason to go with a more recent VR, that specifically claims compatibility with LiFePo4 battery's😈

[danny_galaga]

I'm very happy with my Carmo, although since it was a new build I wired accordingly. Some things that appealed to me-

 

NOT Italian 😄

 

Less wiring

 

No need for capacitor (either it runs much more quietly, or there's suppression built in)

 

When the engine isn't running, nor is the regulator. It's a mystery to me why the Ducati one can flatten your battery. Perhaps the Ducati bike ignition switch is wired appropriately.

 

I think it might be compatible with Li Fe batteries too.

Edited May 20 by danny_galaga

[skippydiesel]

"No need for capacitor ........"

 

Does this mean that the capacitor is redundant?😈

[spacesailor]

According to a battery maker ,

LFP batteries will take all  th amps your alternator will produce & make it get hot . Leading to alternator failure ..

Don't shoot the messenger. LoL

spacesailor