Will bad house batteries cause 120v shoreline power issues?

"I've also set my charge rate to 50%. It used to be 10%. In what I've read, for 6v batteries, it should be about 10% of the amp hour capacity. My capacity's 460 amp hours (230AH each battery, 2 series strings in parallel, total 460, unless I'm mistaken). My Magnum MS2000 max charging rate capacity is 100A. So setting it to 50% gets me 50amp, which is close to the 10%. I think that's right, at least."

Which is it? 10% of 460AH before or 50% of 100A now? The above is confused.

EDIT--so before at 10% that was of 100A so your charging amps was set at 10 amps? That is with any loads coming first and the batteries second, so how much was going to the batteries ever?

Your 6s can take 33% of 460AH ( 152A) easily for the constant amps Bulk stage. Of course you need a gen that can run that much of a charger--such as a PF corrected inverter/charger with a 150A charger to it with a 3000w inverter-gen.

Amps is not a huge issue when plugged in for an extended period.
However battery voltage is critical and the first indication something is wrong. Anything much below the float setting or about 13.2 volts is failing when plugged in.

Even a 10+ amp charger needs to get on those batteries asap.

Whelp. A week later and the batteries dropped down to 9v again, with the High AC or AC Overload faults. Bummer. So there's something else going on. I've been at this RV park many times over the past 5 years without issue, but maybe my current spot has bad power, or maybe the Magnum's going bad. (I've emailed Magnum to ask if what I'm seeing would be expected if the Magnum was failing.)

I've got the Progressive Industries EMSLCHW50 or the Camco Defender queued up in my Amazon cart. Will wait to hear from Magnum before ordering.

I've also set my charge rate to 50%. It used to be 10%. In what I've read, for 6v batteries, it should be about 10% of the amp hour capacity. My capacity's 460 amp hours (230AH each battery, 2 series strings in parallel, total 460, unless I'm mistaken). My Magnum MS2000 max charging rate capacity is 100A. So setting it to 50% gets me 50amp, which is close to the 10%. I think that's right, at least.

Thanks for the update with the answer to the question. (I learned something from this thread too)

Hopefully final update:
I got 4 new batteries yesterday. Installed this morning. I wasn't clear on this earlier but they're Group GC2 6-Volt, and NOT Group 24 like I thought. Which makes more sense, because I couldn't find any flooded (not sealed) 12v batteries.

The old batteries are all reading right around ~5.96-6.06v.

With new batteries in, the Magnum's not flashed a fault or acted up at all. Also, I emailed Magnum and they got back to me pretty quickly saying that bad batteries will make the Magnum act up in strange ways:
> Yes, if the batteries aren’t able to hold a charge and we are trying to load them down, you could see all sorts of odd things. If the batteries are really old and just won’t maintain a charge no matter what, it’s best to get new batteries.

The strange thing that I still haven't figured out is why a few of my outlets were losing power. The outlets in question are the furthest back in my coach, closest to the inverter. I'm wondering if perhaps those outlets might be wired differently from the rest. (Like maybe they're dependent on the inverter, even when plugged into shore power. Not sure that makes sense.) Either that or the power from the RV park was acting up at the same time, and it was just a coincidence.

All in all, I think I'm in better shape. If I see issues with these new batteries, I'll start digging into the Magnum's settings.

Thanks for everybody's advice. It's greatly appreciated.

Further updates:

I ordered a new FlowRite pump, as my old one was a little corroded. I'd thought it was still working fine, but based on how much water went in with the new pump, the old pump may have been far less effective than I'd thought. (My battery compartment has almost no extra space, so it's impossible to check on the levels.)

So the batteries are now full, though still old and possibly in bad shape. Last night, after filling, all the 12v lights continued to dim and flicker, though I haven't had any issues with the AC in a few days.

The Magnum remote continued to blink a fault of Overtemp or No AC In up until this morning, when it was stuck on "High ACV", though I believe I also saw AC Overload right before the High ACV.

I unplugged the shore power for 25 minutes and the fault didn't clear, so I reset the Magnum and topped off the batteries again. Then I plugged into the next spot's 30amp, as our neighbors just left. Same issues, so it doesn't look like there's an issue with the 30amp AC coming from the RV park.

Tested the batteries with my multimeter. I got readings of ~4.5-5v. The interior Magnum remote says ~9v. (This morning it was up around 12v, but it's been dropping.) EDIT: They're up to ~6.3v each and the remote is reading 12.7v. I believe the 4 batteries are 2 groups, so perhaps that's about what they should be, and indicates the interior reading is accurate.

Right now, the Magnum is sort kicking on and off the fan ever second or so. 1s on, 1s off. Was doing that for 15/20min.

My current plan is: Get new batteries this evening and install them tonight or tomorrow. If the problem goes away, it was the batteries. If the new batteries have the same issue, I'll swap the old back in and look at getting a pro to diagnose or replace the Magnum. But the batteries are 6yo anyway, so probably wouldn't hurt to get new ones.

Also, I don't think my Magnum is a converter. Only an inverter and charger. I'm not sure if there's a converter elsewhere on the rig, but based on the battery voltage and the state of my 12v lights, my hunch is that my rig simply needs the batteries to have any 12v power. I'll confirm that when I take the batteries out, I suppose, and I'll update here.

UPDATE: For the past few hours, the Magnum's been charging fine, and the batteries are now ~12.7v. I'm going to delay on the batteries until tomorrow, to see what another day looks like.

2oldman wrote:

Terryallan wrote:
I don't need to know how it works. Just like my vehicle.

Yah, vehicles are quite different from your RV.

I guess it just depends on your DIY proclivity. If you want to install an inverter or solar yourself, you better darn well know how that all works first! Having stuff like that done is not only expensive, but you don't really know what you have. A simple problem can be a real hassle if you need to take it back to a dealer when a voltmeter was all you needed. That can make life much harder than it needs to be.

That said, there's a lot of RVers out there who are fat and happy not knowing any of this.. which works for them.

We camp 5 or six times a year. The only thing I do to the TT besides regular maint. Is,and wash, and wax. Which I do know a lot about. I know quite a bit about towing as well. And of course tires and rims. The only mod I want to do is chrome rims.


As it sits. The TT does exactly what I bought it to do. I sleep in it, and take showers in it. that is what I wanted it for.

DPDT relays is how an IN verter (not CON verter passes shore power for hotel loads.

The CHARGER section of the IN verter is connected BEFORE the AC shore power enters the In verter. When the relays relax the In verter cannot send IN verter generated power backward toward the shore power cord and plug.

With the number of CON verter brands on the market it is always best to review the manual that came with the CON verter to see if the manufacturer OKs the powering of the rig with CON verter power only (sans batteries)

Costs nothing to read a manual. Many of today's huge rigs an consume a lot of AC and DC power.

It works! Is no substitute for knowing that you are operating it correctly. IT WORKS! I can drive up an off ramp at 3 AM in the morning and drive in reverse for 10 mile without encountering another motor vehicle. It Works!

When it does NOT work and a person argues with a qualified technician that is taking time to explain why it no longer works, is sort of ridiculous, isn't it?

Here it is on page 16 of your user manual

"Doesn't matter. It should work"

Terryallan wrote:
I don't need to know how it works. Just like my vehicle.

Yah, vehicles are quite different from your RV.

I guess it just depends on your DIY proclivity. If you want to install an inverter or solar yourself, you better darn well know how that all works first! Having stuff like that done is not only expensive, but you don't really know what you have. A simple problem can be a real hassle if you need to take it back to a dealer when a voltmeter was all you needed. That can make life much harder than it needs to be.

That said, there's a lot of RVers out there who are fat and happy not knowing any of this.. which works for them.

dougrainer wrote:

Terryallan wrote:

time2roll wrote:

Terryallan wrote:
Hmmm. Every thing in my TT works just fine without a battery connected, as did my last TT. Never a problem

What inverter/charger do you have?

The one that came with it. Not something I look at. It works, as did the one in the last TT. That is all that matters.

No, WHAT matters is KNOWING what you have and are talking about. You DON'T. Doug

It works. Don't matter what it is. Should it ever stop. then the repair man will need to know. Don't make life harder than it has to be. In my life. If it works, does what it is supposed to do. I'm happy. I don't need to know how it works. Just like my vehicle. There are thousands of components in it that I don't know how they work. But until they stop working. I'm good.

BTW. There are thousands of components in your vehicle that you don't know how they work either. But it's OK.