My Electric Shorts

[MyronL]

Admit I came close to throwing in the towel and towing the thing to the experts at Tom's RV. It crossed my mind. But now, feeling vindicated - I suspected the experts were not going to find that short, and I would get a bill reflecting a large hourly rate. Anyway, how could I let some piddle-ass stranded wire beat me?

[MyronL]

Need a “Jesus nut” gut-check. I am soon about to install my 190 watt Grape solar panel on the roof. Will have my two 100 watt portables on the side to supplement it.

However, (after all my electric shorts problem got done with) -- I now notice my Morningstar MPPT-15L solar controller is dead.

I keep it in the tongue box, wires running in from the solar panels and out to the Battleborn Lith battery. No fuses are blown. No clue what happened since it was never connected to solar since last year. Need advice.

See no solution but to buy a new unit. Not a cheap decision. Will it be a Victron Smart Solar MPPT 100/30, $226 new on eBay now, or another Morningstar Charge Controller, Sunsaver, MPPT Type, 15A, SS-MPPT-15L $279.33 new or $150 used on eBay (?)

What’s a “Jesus nut?” A Huey pilot once told me that’s when a nut comes loose and you holler Oh, Jesus!

[HABBERDABBER]

Before you drop a lot of coin on a new or different solar controller, the only advice I'd offer is to triple check the old one....all connections disassembled and reassembled, clean up electronic contact surfaces, etc., etc.



I just had a gremlin pop up in my tug, a dead no start. I found a loose battery connection due to a new battery & side post battery wire contact case redesign, and my added on brake controller wires, etc., stopping good contact.


Contact. It's crucial, it's everything.


After that.....you're on your own. What would fry the Morningstar controller? Could your earlier electrical gremlins have done it in?
Is there a remote way to test it's operation with your portable panels?


Well, Sparky, I wish you well.

[RangerMan]

What’s a “Jesus nut?” A Huey pilot once told me that’s when a nut comes loose and you holler Oh, Jesus!

No mistaking a Huey. Such a distinctive sound. I can still hear those 'Slicks' flaring at the LZ when my mind wanders away. At my age, it doesn't wander far!

[Vermilye]

I've been pleased with the Victron 100/30, although with 320 watts of solar on the roof & a 160 watt portable panel (the rooftop tilted to the proper winter solar angle) I managed to hit 30 amps on some cold mornings. Victron says not to go over the voltage rating, but the controller will limit small overcurrents to the unit's rating. Still, I hate to "throw away" any amp hour - I wish I had purchased the 100/50...

[MyronL]

Thanks for that, Jon. Thinking will get the Victron 100/30. I have no plans to exceed my current solar load.

[Centex]

Originally Posted by Vermilye

I've been pleased with the Victron 100/30, although with 320 watts of solar on the roof & a 160 watt portable panel (the rooftop tilted to the proper winter solar angle) I managed to hit 30 amps on some cold mornings. Victron says not to go over the voltage rating, but the controller will limit small overcurrents to the unit's rating. Still, I hate to "throw away" any amp hour - I wish I had purchased the 100/50...

Just FYI for others following, Victron has an IMO really nifty Excel spreadsheet tool to aid in matching their MPPT controllers to one's particular PV array. It allows entry of specification data for non-Victron PV panels, supports complex serial / parallel PV array schemes, and generates a warning-flag for those low temperature / cold-morning situations when potential loss of precious amp-hours is applicable.

Link to download the "VE MPPT Calculator v4.0" Excel spreadsheet direct from Victron Energy: https://www.victronenergy.com/upload...-Calc-4_0.xlsm

Example screenshot attached, Have Fun!

[richm]

Originally Posted by MyronL

However, (after all my electric shorts problem got done with) -- I now notice my Morningstar MPPT-15L solar controller is dead.

Dunno if you want to diagnose the MPPT, but I can make some suggestions if you want them.

[MyronL]

Well, Richm, it's currently just a paperweight now so have been thinking I might open it up and look around for burned replaceable capacitors, etc. That's beyond my pay grade but what the hey, right? So what you got?

[richm]

Hey MyronL, yea, the capacitors are worth a look. There should be at least two largish for the solar input and battery output, and over-voltage can pop them.

Inexpensive controllers often have a fuse on the circuit board, hard soldered or not. That's worth looking for as well.

Inexpensive ones may have poor heat sinks, so cracked mosfets is something else to look for.

They often power themselves from the solar input, so if it's dead, verifying the voltage on the solar input is within the range supported by the controller is a good check.

[John in Santa Cruz]

In electronics, we frequently refer to any sort of small spring clip, such as might be found on a small motor shaft, as a 'jesus clip', because you go to remove it, and its "Jesus, where did that go??"

[cpaharley2008]

We call them snap rings......

[Iowa Dave]

We were tasked with mowing vacant lots one summer. My operator was mowing 3 foot tall weeds with a flail mower. His helpers had walked the lot but had missed a baby bed mattress which he straddled with the tractor tires. Let me tell you about a can of worms with coil spring steel wrapped around the knives and the shaft on the mower. We took the better part of the afternoon cutting those springs out. Then we retired to the local speakeasy. It was a dive that couldn’t be called a lounge and there was never a showgirl within 20 miles but it was still Lucy’s Showgirl Lounge. Lucy was the bar keep. Hang in there Myron, better days ahead.
Iowa Dave

[MyronL]

It was in the low eighties yesterday here and last night it never got below 53 degrees. Perfect for finally installing my solar panel with that VHB (very high bond) tape on the trailer roof. Also trying out my new telescoping ladder that expands to 12 feet and collapses down to 3 feet. very cool.

This project has been going on since March. Expect to be drilling holes (ouch) up there pretty soon. Then another road test documenting vibration and, once the new controller gets here....Hoping to get on the road again – maybe next month.

Got to get away!! Southern Utah and Nevada - or Colorado, on my mind.

[MyronL]

Good thing I remembered what I read about protocol when using the 3M VHB tape. After careful surface prep when ready to apply it to an Escape roof be sure to lay heavy weights on top during the curing process. We know that roof is not flat but I thought I had everything covered, and - then after laying down the frame I saw gaps under the frame. After putting up the cinder block weights I came out the next morning expecting to deal somehow with them gaps I saw. But, they were all mostly gone.

[sameo416]

Originally Posted by MyronL

Good thing I remembered what I read about protocol when using the 3M VHB tape. After careful surface prep when ready to apply it to an Escape roof be sure to lay heavy weights on top during the curing process. We know that roof is not flat but I thought I had everything covered, and - then after laying down the frame I saw gaps under the frame. After putting up the cinder block weights I came out the next morning expecting to deal somehow with them gaps I saw. But, they were all mostly gone.

Myron, thanks for sharing your wire short experience. There are chapters on house fire investigation written about staples into wire bundles as a competent ignition source. So not a bad outcome overall in spite of all the sweat to trace the fault.

One way to find shorts in wiring is using a time domain reflectometer. Done this on aircraft successfully and in home wiring, but it's a pricey piece of test equipment. Allows distance to fault measurement which is super for checking wires that are hidden from view.

On the "Jesus nut" trivia I first learned this term in aerospace work as the main rotor retention nut for helicopters. Never encountered the term in fixed wing work.

[John in Santa Cruz]

Originally Posted by sameo416

On the "Jesus nut" trivia I first learned this term in aerospace work as the main rotor retention nut for helicopters. Never encountered the term in fixed wing work.

that one might have had a different origin..... if that nut fails in flight, anyone on board had best be praying to their God(s).

[RangerMan]

Originally Posted by John in Santa Cruz

that one might have had a different origin..... if that nut fails in flight, anyone on board had best be praying to their God(s).

I would suggest placing their head between their legs and kissing their hinnie goodbye.

[MyronL]

You never forget your very first ride in one... or those wild and crazy guys who flew them. Taught me great respect for the seat belt. BUDDA-BUDDA-BUDDA!

Sameo -- when I saw those uncovered burnt wires it also scared me silly.

[sameo416]

Originally Posted by MyronL

You never forget your very first ride in one... or those wild and crazy guys who flew them. Taught me great respect for the seat belt. BUDDA-BUDDA-BUDDA!

Sameo -- when I saw those uncovered burnt wires it also scared me silly.

I was a fast jet guy but had a few chances in twin Hueys and the Griffin (a green Bell 412) to fly with the doors off low and to rappel off the skids. Always memorable.

Fuses save lives and trailers! Overcurrent protection doing exactly what its intended to do.