Voltage Regulator Failures

[sonex1374]

We're all getting at the same basic problem with sourcing after-market regulators, and that's the difficulty in finding a good quality one. The only way we can address this is to be a specific as possible. I'll ask everyone contributing to this thread to be specific, including manufacturer name and part number. Many of these regulators that appear on Amazon or EBay all look the same, so without specific details to work with it's hard to make an informed choice. Price is certainly not an indicator (or a guarantee) of quality.

So, for those that have specific details of good (or bad) regulators, please contribute your info to the knowledge bank.

Jeff

[Paul Johnson]

I bought my Jabiru 3300 in 2014 and installed it in a Bristell aircraft, I also installed a crowbar to protect my instruments against voltage surges, I don't know how beneficial this is with a permanent magnet alternator. After about 15 hours of flying the crowbar tripped, the first indication of this was the loss of RPM indications on the Dynon EMS120, the cowls were removed and a thorough inspection carried out, a little arcing was found on one of the faston terminals on the relay which is part of the crowbar circuit, the relay and faston terminal were replaced but a few hours later the crowbar tripped again. No indications of over voltage had been observed so we thought the crowbar maybe oversensitive, the crowbar was removed and all seemed fine for the next few hours of flying until a light smell of burning was noticed on a local flight, the master switch was put in the off position and a return to the airfield was made with the burning smell still remaining.
After landing the cowls were again removed and it was then we saw the inside of the voltage regulator had melted and a tar like substance was running down the firewall. The voltage regulator was only 25 hours old and was the one supplied with the Jabiru engine and had no makers emblem on it " it was not a Kubota" a Kubota was ordered and fitted with no more problems.

[Corby202]

A lot of flyers in Australia use these, http://www.powermate.com.au/

[tonyr]

I have replaced 2 regulators in 220hrs

The original item that came with the brand new engine (circa 2012 - 2200) failed after about 39 hours.
The unit is mounted high on the fiirewall alongside the filler neck, but has no external cooling air supplied to it.

I purchased an aftermarket item from eBay - Kubota 15531-64603 RP201-53710 UTV RTV500
https://www.ebay.com.au/itm/New-VOLTAGE-REGULATOR-RECTIFIER-Grasshopper-Kubota-185530-RP201-53710-/271095558363?hash=item3f1e8df0db

Suspecting the previous unit failed due to overheating, I mounted a computer fan on a bracket over the replacement regulator. The fan is powered whenever the master swtch is on.
That was 180 hours ago.

As alluded by others, I believe excessive heat leads to early failure if there is no supplemental cooling.

As a footnote, I also use a terminal block for the alternator leads, instead of going through the connector to prevent issues with the spade connectors overheating.

[lgsievila]

As a footnote, I also use a terminal block for the alternator leads, instead of going through the connector to prevent issues with the spade connectors overheating.

I also cut the connector off and went through a terminal block. It would be interesting to know how many failures occurred on regulators where people used a spade connector instead of a terminal block. As a side note I have a Kubota tractor with over 1400 hours on it that has the exact same regulator that is on my plane.

[DCASonex]

Suspect you are right about heat being major problem. Have had same regulator on my Sonex since 2012, even though changed engine to a CAMit. It is also high on firewall, behind the left cylinder bank, but have a cooling air jet from intake plenum blowing on it. Do need to orient with fins vertical for good airflow and for convection cooling after shutdown. The original spade lug connectors on Jabiru and CAMit flywheel alternators are grossly undersized for the current. Replacing them with good quality lugs rated 30 amp or better seems to eliminate that problem.

David A.

[DCASonex]

The Powermate regulator looks good, but the specs show it for 8 amps, while our flywheel alternators are rated from 17 to 20 amps (and I have briefly seen higher when first going to WOT as it recharges my EarthEx battery) ???

David A.

[mike.smith]

I have replaced 2 regulators in 220hrs

The unit is mounted high on the fiirewall alongside the filler neck, but has no external cooling air supplied to it.

OK, I have an AeroVee and not a Jabiru, so maybe not the same, but that's the location where I have mine (Sonex-supplied) and after 270 hours, no failures at all, with no supplemental cooling being supplied. All I did was mount it on short stand-offs so it is not touching the firewall.

[N111YX]

After 778 hours and 8.4 years of operation, My stock voltage regulator finally quit, I noticed a small charging value happening (12.4V) before takeoff but it went to battery voltage soon after takeoff. Incidentally, I lost my tachometer on the same flight. It shows zero on my Dynon D-180. I'll add that I have no cooling on the regulator.

I guess the old lady is showing her age.

[builderflyer]

Are you sure it isn't the alternator itself that failed? If your tachometer takes its feed from one of the two alternator wires as does mine, it may explain why you lost the tachometer as well. Just wondering.

Art,,,,,,,,,,,,,,,,,,,,,,Sonex taildragger #95,,,,,,,,,,,,,,,,,,Jabiru 3300 #261