One more bad Voltage Regulator - Page 13

Bill_H · #**121** 07-30-2015, 07:27 PM

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.

Tony_T · #**122** 10-06-2015, 08:18 PM

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.

RFSchaller · #**123** 10-06-2015, 08:39 PM

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?

Hal-san · #**124** 10-06-2015, 09:43 PM

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.

f1rocket · #**125** 10-07-2015, 07:32 AM

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.

BigJohn · #**126** 10-07-2015, 07:43 AM

Quote:

Originally Posted by RFSchaller

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.

Hotscam · #**127** 10-07-2015, 12:11 PM

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.

RFSchaller · #**128** 10-07-2015, 12:48 PM

John, my regulator is in the original location on the firewall shelf. It had about 380 hours on it.

Rich

WingedFrog · #**129** 10-07-2015, 04:36 PM

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/communit...&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.

Godo · #**130** 10-08-2015, 01:05 PM

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