Weird! -But okay now?

[DonTom]

My 2022 Ford Class A-Entegra 27A Vision.

I was just sitting here typing on this computer and my GPS which was off, turns on. Running from the stock inverter to a USB port on a power strip. That is so it will NOT go off with the engine or go to internal battery.

Next, in about five more seconds, my refrigerator has a "low DC alarm".

Then the inside lights flicker. Then they all go out. I grab a flashlight (2200 hrs here).

I check the RVs house batteries from the RVs own panel, one light of four possible, showing very low.

Generator not getting enough power to crank. Slides are out and would not come in.

Then I lose ALL DC power. Nothing at all.

I then noticed the "salesman switch" turned itself off.

I turned it back on and now all is back to normal. At least for now.

But what really happened? I mean what could have been the cause? Perhaps a relay contact that the salesman switch controls? Something in the transfer switch? What is inside the transfer switch? Perhaps a small computer that can crash? I did run the genny around two hours earlier.

Has this ever happened to anybody else here?

My Victron app, under stock house batteries is now showing 12.45 volts. 97% soc, drawing 5.7 amps total load. I have the stock inverter on so I can charge this computer and other things, so there is some load. So all looks perfectly normal since all this happened around 20 minutes ago.


-Don- Bean Flat, NV

 

[John From Detroit]

Sales switch off means battert SLOWLY discharged. Some loads connect to the battery before the switch... Turning it back on recharged battery from converter.

HOWER Lights should be on the converter side of that switch so you needed flashlight.
(GPS should be too less it's a tracker)

 

[Kirk]

. So all looks perfectly normal

Are you connected to shore power? If so could you have experienced a power surge?

 

[DonTom]

Sales switch off means battert SLOWLY discharged. Some loads connect to the battery before the switch... Turning it back on recharged battery from converter.

HOWER Lights should be on the converter side of that switch so you needed flashlight.
(GPS should be too less it's a tracker)

Are you connected to shore power? If so could you have experienced a power surge?

No, 100% boondocked in every way.

This is at a rest stop that only has a place to dump trash and a picnic table--nothing else at all.

-Don- Bean Flat Rest Area, Hwy 50, NV

 

[boatbuilder1]

Not sure what batteries you have but 12.45 volts is not 97% SOC. On lead acid batteries it is more like 75% SOC. I am wondering if there is a loose connection that is making the system think it is low and causing the shut down.

 

[Primerump]

I then noticed the "salesman switch" turned itself off.

Gremlins in the system, little critters are hard to catch BTW .. LOL

 

[DonTom]

Not sure what batteries you have but 12.45 volts is not 97% SOC. On lead acid batteries it is more like 75% SOC. I am wondering if there is a loose connection that is making the system think it is low and causing the shut down.

That was under load, but I wondered the same myself. I will calibrate my Victron Smartshut for 100% SOC when there is no doubt it is fully charged,

The two stock six volt lead-acid batteries.

-Don- Ely, NV

 

[DonTom]

Gremlins in the system, little critters are hard to catch BTW .. LOL

Yeah, intermittents can be tricky, especially when such happens while stationary.

BTW, I think it happened again but while driving this time, but I could not check while driving. All I know for sure is the radio went dead and my inverter lost power for around five seconds and then all came back to normal without me doing anything.

I will check battery connections and etc. when I get to Sacramento Pass and set up.

-Don- Ely, NV

 

[bigbAZ]

We had similar symptoms when one of my 6 volt FLAs developed a bad cell. It gave us fits for a few days till I figured it out. The symptoms would come and go, the fridge would give us the low voltage alarm. We were even plugged in and still had issues. the only issue that doesn't match yours is the switch shutting itself off, that never happened, and the lights going out but like I said we were on shore power as well. I would suspect you have new batteries in your future.

 

[Mark_K5LXP]

It sounds a lot like electron insufficiency. With the popularity of EV's being what it is, all the available electrons are spoken for. It's looking like RV's can only operate at non-peak hours.

Do you have a battery monitor that shows voltage and current real time? That along with a known load can reveal a battery, switch or terminal issue.

Mark B.
Albuquerque, NM

 

[DonTom]

It sounds a lot like electron insufficiency. With the popularity of EV's being what it is, all the available electrons are spoken for. It's looking like RV's can only operate at non-peak hours.

Do you have a battery monitor that shows voltage and current real time? That along with a known load can reveal a battery, switch or terminal issue.

Mark B.
Albuquerque, NM

Problem solved!

When I got here at Sacramento Pass, and parked, I leveled the RV (I now assume that works from the engine battery, even though the controller stuff is located next to the house batteries). Then I went to pull the slides out. I looked at the RV's house battery monitor just before I put the slides out, which showed all four LEDs let up (full charge). As soon as I pressed the button to put the slides out, I lost ALL DC house power again!

I thought to myself "this is good!" It is staying out, giving me time to troubleshoot while still light outside.

So I go to the house battery compartment (above the propane tank which I think is a stupid location) with my VOM. I check voltages and it was a very simple fix.

All I needed to do was to tighten the battery positive bolt. It did seem quite tight as it was, and no noticeable corrosion, but my VOM doesn't lie. At first, I thought I had an intermittent battery (I have seen lead acids do that twice in my lifetime and one of the times was a battery in a new car). But then I noticed the battery positive had voltage but the connector did not. As soon as it tightened it, I heard the refrigerator fan come on, proving it is all fixed.

A little strange that it's very first symptom was when nothing was being touched, but I have seen stranger things happen.

-Don- Sacramento Pass, NV (my very first message where my new Starlink is truly needed!)

 

[Arch Hoagland]

Thanks for the update, glad to hear you got the problem solved.

 

[DonTom]

I then noticed the "salesman switch" turned itself off.

That is NOT what happened! It is a latching relay, I discovered that when I lost all power thinking the switch turned itself off because it was not lit. It had no power to light, making it look like it went off.

When I regained battery power, everything came back on without me touching the salesman switch.

I forgot that they always used latching relays in motorhomes. When the power came back on after I tightened down the battery screw, it refreshed my memory that it is not possible for it to switch itself off without voltage to make the latching relay change state.

-Don- Sacramento Pass, NV

 

[John From Detroit]

I forgot that they always used latching relays in motorhomes. When the power came back on after I tightened down the battery screw, it refreshed my memory that it is not possible for it to switch itself off without voltage to make the latching relay change state.

There are two types of latching relays. You described the magnetic latch type used in motor homes and trailers.


The other type, often used in "Smart" switches and outlets. will "Default" if power is lost Depen dingb on the device that default can be off or on.


But for the aux power (Salesman switch) relay yes, they use the type you describe.


There is a good reason to use the other kind in smart outlets and switches. Power fail and restore to safe mode. (lights on, devices off)

 

[TheBar]

These symptoms are very typical before an alien abduction. How many times have you noticed time missing or were you awake while being in an electric alien RV?

 

[Mark_K5LXP]

Aliens driving EV's? I thought they were more advanced than that.

Would prolly be a good idea to check all terminals/connections. The torque exerted on a pinch bolt isn't all going towards compression on the post, some goes towards deformation of the terminal. I generally observe a bit of movement of the 'ears' to know it's compressing. Also a good time to proselytize about periodically servicing posts and terminals. I service every battery in my 'fleet' once a year - remove, rinse off, wipe down, brush or cut posts, check/fill electrolyte, grease and reinstall. Sounds overkill but is easy to do and resets the clock on corrosion and loose connections.

As a sanity check you can test the integrity of all the connections quickly and easily by loading (or charging) with a nominal current (say 10-20A) and testing for voltage drop as you did to discover your open connection. A 'good' connection will have only a handful mV of drop, and you will see right away if one is an outlyer before it goes thermal or opens up. If you're extra OCD you can log the measurements for future comparison.


Mark B.
Albuquerque, NM

 

[bigbAZ]

I thought most house batteries have marine type terminals?

 

[DonTom]

I thought most house batteries have marine type terminals?

Mine are two Harris 6-volt batteries in series. Uses 13 mm bolts. I used a metal socket wench being extra careful.

Perhaps someday I will buy a set of these. There has been enough times I needed such a set.

-Don- Sac Pass, NV

 

[DonTom]

some goes towards deformation of the terminal.

Yeah, I have heard of such issues before where a bolt can increase resistance when being overly-torqued, caused by the deformation from the bolt stretching. Such is usually only an issue with extremely high currents.

I did retorque all the bolts, perhaps a little too much. But in RV House batteries which will need to be replaced in a few years or so anyway, I don't think it is worth worrying about. Currents are not all that high in RV house batteries.

-Don- Sac Pass, NV

 

[DonTom]

I then noticed the "salesman switch" turned itself off.

I turned it back on and now all is back to normal. At least for now.

Things such as this make me wonder what really then happened. Perhaps the power decided to come back on the same instant I touched the switch? What are the odds of that?

-Don- Sac Pass, NV