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General Category => General Discussion => Topic started by: alyaz on April 14, 2019, 09:06:56 PM

Title: Help with troubleshooting?
Post by: alyaz on April 14, 2019, 09:06:56 PM
Our Perkins 10 kW diesel generator has been tripping its 50a breaker (mounted on the generator) starting Thursday night.  We had been running the gen, charging the batteries and watching some TV.  It had gone through almost a full absorb and when I next checked the Magnum remote, it showed that it was not ‘charging’ any longer but was inverting.  So I initially thought that maybe my 1.5 hr timer I had set on the remote had finished and that the diesel gen had been shut down via the AGS.  However, the gen was still running  I went out and found that the gen breaker had tripped.  I reset it and turned the gen off.

The next morning I started the gen from the remote and it started to bulk cycle but almost immediately the gen breaker tripped.  I went out and reset it but it tripped off again.  I wheeled up our backup Porter Cable / Honda gen and plugged into the bypass and started it up.  The Magnum remote showed it go into bulk charge and into absorb.  I turned the gas gen off about an hour later to let the daylight finish the battery charge and to head into town.

While in town that day I squeezed a couple phone calls in and spoke to the Hardy/Perkins tech guy.  From what I told him, he believed the Square D breaker on the generator needed replacing.  So I started looking for a replacement breaker and Square D doesn’t make that breaker any longer.  Short story, I picked up another electrical box and a 50a 2 pole breaker in town, thinking I would just bypass the gen’s original breaker.  Well, the regulator etc is in the box that the original Square D breaker is and for me it wouldn’t be that simple.

Anyway, the next morning the diesel gen breaker tripped again.  I did the same thing and the gas gen charged everything fine.  This was on Saturday (yesterday) and an electrician was on island.  He stopped by and he checked the wiring and most things upstream of the gen.  We couldn’t get the gen breaker to trip - however the breaker had been removed from the housing on the gen and was resting on a container.  He put his clamp meter on it and we put various household AC loads on and off but it wouldn’t trip.  He checked electrical connections in various breaker boxes, the bypass box, inverter, etc.

Today, I woke up (the breaker was back in the housing on the gen) and started the gen.  The breaker tripped almost immediately.  So I hooked up the gas gen and ran it, and the Magnum showed the batteries go through a bulk charge and into an absorb, without incident.

I later removed the breaker from the housing on the gen and let it rest on a container.  I started the gen and forced a ‘bulk mode’ on the Magnum remote.  It ran without incident.  I then tried it a bit later in the day and it ran without incident through another forced bulk mode charge.

I have never had any incident with the Magnum inverter but did check the default codes and there was one there for AC overload.  I will call the Magnum techs tomorrow.  I don’t know if a tripped breaker would possibly cause that or not.

So my question(s) are; if a breaker was weak, would the vibrations from being on the gen be enough to make it trip? 

I keep thinking if the little gas gen (4500 watts) can run everything upstream of it without incident, that the problem is with the diesel gen or the diesel gen breaker.  However if it is a diesel gen issue, why did it run and charge okay with the breaker out of the housing both when I tried it today and when we (the electrician) was here yesterday.

Any ideas would be appreciated.  Sorry for the long post and thanks if you took the time to read it :)
Title: Re: Help with troubleshooting?
Post by: ClassicCrazy on April 14, 2019, 09:43:28 PM
Did the electrician pull the wires out of the breaker and look at them ?
If they were crusty they should be trimmed back to good wire.
Usually first thing to check is for loose connections at terminals - the wire can compress over time and the terminals at the breaker need tightening. If they had been loose and bad connection they may have gotten hot ( high resistance ) and that is what can make a breaker trip . So not knowing anything else about your system the first thing to do is make sure those connections and all of them in the box are clean and tight and if they are aluminum wires there should be that anti oxidation stuff on them.  Sounds like you checked all that though.

Larry
Title: Re: Help with troubleshooting?
Post by: alyaz on April 14, 2019, 10:40:07 PM
Yes thanks.  It appeared to me that he did check everything in the box.  He looked for frayed wires and retightened everything.  He did get a part turn on one of the breaker terminals/wires, but regardless, back in the box it tripped again this a.m.  He did say he wants to replace that wire run in the future as it is ‘cab tire’ wire in there now (copper) and wants to use a heavier gauge of armour wire instead. 
Title: Re: Help with troubleshooting?
Post by: alyaz on April 15, 2019, 12:25:22 PM
Just an update.  With the breaker outside the box, resting on a support, the gen ran fine this morning.  Ran it through a bulk and into a absorb with the typical morning loads on it.  So at this point I gotta think it is the breaker.  Definitely going to mount a new breaker on the wall, versus replacing one attached to the stock/factory placement on the gen.

The tech at Magnum agreed the fault codes on the remote were a result of the tripping breaker.

The tech at Hardy/Perkins is still confident that the breaker is weak.
Title: Re: Help with troubleshooting?
Post by: mike90045 on April 16, 2019, 06:36:02 PM
Quote from: alyaz on April 15, 2019, 12:25:22 PM
......The tech at Hardy/Perkins is still confident that the breaker is weak.

That's why I run my generator into a box with hardware store breakers. $20 if they go bad.  I switch them on and off, and leave the rare breaker on the generator, alone, so it will last.
Title: Re: Help with troubleshooting?
Post by: alyaz on April 16, 2019, 09:09:56 PM
Quote from: mike90045 on April 16, 2019, 06:36:02 PM
Quote from: alyaz on April 15, 2019, 12:25:22 PM
......The tech at Hardy/Perkins is still confident that the breaker is weak.

That's why I run my generator into a box with hardware store breakers. $20 if they go bad.  I switch them on and off, and leave the rare breaker on the generator, alone, so it will last.

I hear ya.  Live and learn.  I never did like having the breaker mounted on the gen.  Funny thing though is that I probably flipped that breaker on and off maybe three times in eight years.  So, it wasn’t a case of wearing it out.  When I spoke to the Hardy/Perkins guy he didn’t come out and say it but it sure sounded like there have been numerous issues with the Square D breaker that was on the unit.  Those suckers are about $300-$400 too.  Not sure why they would be so expensive.  So it’s a no brainer to bypass that goofy ‘I-line, line load’ style breaker and mount a basic 50a breaker on the wall.  :)
Title: Re: Help with troubleshooting?
Post by: RossW on April 17, 2019, 10:32:09 PM
Quote from: alyaz on April 16, 2019, 09:09:56 PM
So it’s a no brainer to bypass that goofy ‘I-line, line load’ style breaker and mount a basic 50a breaker on the wall.  :)

Just playing devils advocate for a moment...

The rigid wiring of the genset is unlikely to get damaged. Well, less likely to get damaged than a (semi)flexible lead from it to the wall.
If the dog chewed the cable, or that cable were to suffer crush damage, there's no protection to the generator or its wiring.

I'm sure it's different between countries, but I'm pretty sure that over here where I am at least, there MUST be, by law, a breaker on the genset. It may even require RCD, I can't recall.
Title: Re: Help with troubleshooting?
Post by: alyaz on April 18, 2019, 09:27:17 PM
Yes, valid concerns for sure.  Here it is within 12 feet or something.  I asked the Regional District if it was an issue if I mounted it on the wall, within 3 feet of the genset.  They told me that was acceptable.  I am using #6 Armour Cable for the run so that won’t be an issue for degradation, pests, etc.