Electrical & battery advice needed

[BVJandJ63]

Originally Posted by RVingNow

So you're using equalization to charge your batteries because they'd never fully charge at 13.7v. The absorption phase takes hours and is around 14.4v. While your batteries may still have some life left in them, I think there's still a charging system issue.

Hmmm... I don't intend to be using equalization instead of the regular charge cycle (BULK, ABSORB, FLOAT, FULL/SAVER) to charge my batteries. I just did a couple of equalization rounds to "shock" them and see if they would start taking a full charge again and not discharge so quickly. I don't plan to do another equalization charge for at least another month or so and only if S.G. readings start to drop again. So far, so good, but I haven't put much of a load on them, yet--I'll do that later tonight/tomorrow.

Also, RE: the ABSORB phase; according one or another table that I used/was pointed to along this thread, my absorption time is only 90 minutes for 460Ah bank at 40-50% charge rate. That seemed to work, as did the shock treatment but time will tell...

[BVJandJ63]

Originally Posted by C.Martin

[*]Since you bought the Smartshunt...did you buy the ME-BMK-NS? It saves a few bucks, since you don't need two actual shunts...just the circuitry.

I have pictures of how I mounted my shunt when you're ready...others have great techniques for mounting as well. You can chose one that feels right to you.

Absolutely! I've been double checking all of the advice in this thread to make sure I'm not missing something and that I'm not wasting anybody's time. =) So I am upgrading with the potential/future solar panel addon in mind (I bought the ARC and the BMK-NS to get me started). If you (and others) have pictures or thoughts about why one install has more advantages than another, I'm all ears/eyes.

Meanwhile, here is what I believe/hope to be the final report of my house battery bank status. It appears positive so far, especially compared to where the S.G. readings were when I started this thread:

• Before doing any EQ charges (readings average per battery--did not record each cell separately):
  • Front Right: ~1.12
  • Back Right: ~1.13
  • Front Left: ~1.14
  • Back Left: ~1.13
• 4 hours after the first EQ charge:
  • Front Right: 1.24/1.22/1.22
  • Back Right: 1.24/1.25/1.24
  • Front Left: 1.23/1.23/1.23
  • Back Left: 1.24/1.24/1.22
• 4 hours after the second EQ charge:
  • Front Right: 125/125/126
  • Back Right: 125/125/125
  • Front Left: 127/127/127
  • Back Left: 127/127/126
• After leaving the batteries on FLOAT/FULL CHARGE cycle for 3 more days:
  • Front Right: 126.5/126/125.5
  • Back Right: 126.5/126.5/126
  • Front Left: 127.5/127.5/127
  • Back Left: 127/127/126

It is consistent that the front-right battery is the lowest of the bunch (and did not make it to 127)--if you remember from earlier in this thread, this battery is a bit swollen so it might've taken the brunt of the discharge. And, on a possibly related note, I'm wondering if it's ok to have the house power and the inverter positive cables be connected to different batteries--one to each series. The wiring diagram appears to show them both going to the positive post on the back-right battery. Can one of these being connected to the front-right battery cause that battery to discharge more than the others? I remember a statement from the lady who wrote the Newmar battery article you sent me to... she said that, ideally, you connect the positive and negative cables to the far ends of the battery bank so that you utilize every cell in the bank and don't miss a chance to leverage any of them. So maybe having one connected to the far end of each series accomplishes this even if it doesn't match the Newmar wiring diagram?

[*]Victron has a good YouTube content too...describes installation and programming...for the SmartShunt500.

Thank you--I will do a little more research this week to make sure I know what I'm doing before I install the SmartShunt. The one thing I keep reading and that is now stuck in my brain is that, throughout that (and any electrical) installation that requires me to disconnect the ground wires, I need to remove the positive cables from the house batteries before I do anything else.
Q: I believe I need to remove the two large red positive cables from the positive posts on each of the two batteries on the right side of the house battery bank (picture attached) before I start disconnecting and re-routing negative cables to the shunt (or to a terminal block and then the shunt, maybe?). Is that all? Or do I need to also remove the positive cable from the chassis battery bank? Or from the inverter itself?

[*]Yes...RV's are one project after another.

Yes, I don't see an end in sight--makes me want to stick with Vinny long term and not do anything that would render all this effort as wasted because I doubt anyone we sell our coach to is going to pay extra for all of this extra gadgetry and effort that we would most certainly leave in the rig.

[*]I also have a very long thread covering my solar install. You can follow along thru my infancy...to fruition. Mine is but one design...again. others have approached it with differing components and methods...chose again, what fits your personal desires.

I will most definitely find this (and other) threads and do my homework before bugging folks on this forum with solar questions.

Thanks again, Charlie and team! You've all helped a ton--I actually feel like I'm in control again (instead of Vinny's power--or lack thereof--controlling me! =)

[C.Martin]

I don’t really know why the one battery bulged, vs the others...and why the SG is lower.

I’ve observed Newmar doesn’t really worry about the wiring methods you spoke of. There are many wiring diagrams which do follow the “Most Positve & Most Negative” methodology. The theory is...map all your loads...and what distance of jumpers and and cables electrons would have to travel. Compare each battery pair to the other...are they equidistant? Wire is resistance...although very small.

Once you add a shunt...you have deviated from the schematic. If you weren’t...then I usually recommend sticking with the schematic for the sake of the technicians that might perform work on the rig. They, obviously, can figure it out...but they may be well rehearsed at using schematics where available...so —- wild goose chase. I need to redo my schematic...as it still has the old Interstate 8 battery layout. (Which is a mess in my opinion). Since all of your Negatives will be routed to the load side of the shunt...You will have one large cables from the Battery side of the shunt to the batteries. This makes it a good time to place all positives to a bus rail...with a single large positive going to the most positive terminal.

Point of order...Magnum Inverters need to have their positive cable remove from the batteries - BEFORE !!!! - you remove any negative cables. It won’t matter as you tear down for the project...as you don’t yet have sensitive peripheral devices installed (ME-AGS-N, ME-BMK)... but, when you go to reinstall after adding the BMK...it should become habit. The positive to the Inverter gets fastened LAST. This is designed to prevent the inverter from trying to seek an alternate pathway to ground once you remove the inverter ground. If the positive is removed first...it won’t have the potential to fry your BMK or AGS.

In your diagram...the positives are connected to the top pair and the negatives are tied to the top pair as well. If you moved the positives to the bottom pair... then...

Let’s assume the two series jumpers are equal length..and call them S. Both Parallel jumpers are the same length...and call them P. And we can designate a battery as B.

You have two pairs to pass power thru...charging or discharging. Let’s examine how the schematic is drawn for passing power...

Top Pair = B,S,B
Bottom Pair = P,B,S,B,P

You can see the short way is directly thru the top pair.

Now...same scenario,,,but moving the two positive cables down to the bottom pair positive.

Top Pair = P,B,S,B
Bottom Pair = B,S,B,P

Now they are equal... this is the goal. Doesn’t matter if there are two pair, three, or four...you can design your connections to achieve a balanced architecture.

It looks like someone may have tried to do this... moving the grounds and positives around a bit from the original schematic to attempt to balance the pathways each circuit makes thru the bank. Although...I can’t really tell which cable is which to verify that.

When I added my shunt on my old batteries...I didn’t fuss with the positives to balance them. But when I installed the AGM’s...I did place my positives together on a buss, and ran a single positive to the balanced most positive terminal of the bank. Electrons travel the same distance regardless of which pair they travel thru.

[C.Martin]

I mentioned all the negatives going to the load side of the shunt...and only one negative from the battery side of the shunt to the batteries. Well...I lied just a tiny bit. The exception is wiring for the SmartShunt and the BMK.

SmartShunt...will add a fused positive to the bank directly. When you add solar...you’ll want to add the temperature sensing wires...it’s a pair going to a single terminal..the fused line goes to Input 1 and the other (temp sense line) will go to input 2 of the Smart Shunt.

BMK...you’ll have to fashion a fused positive, and a negative. These both go directly to the batteries as well.

ME-BTS...the Magnum temp sensor get connected to a negative terminal directly on the batteries.

Now that I mention this...I don’t see the ME-BTS connected to your bank. We should check to be sure it’s connected. The inverter uses measured battery temperature to adjust the charge parameters. In cold weather it adjust the voltage up...I’m not weather it drops the voltage... This protocol is followed for Lead Acid chemistry...but not for LiFePO4 chemistry.

[BVJandJ63]

Originally Posted by C.Martin

I mentioned all the negatives going to the load side of the shunt...and only one negative from the battery side of the shunt to the batteries. Well...I lied just a tiny bit. The exception is wiring for the SmartShunt and the BMK.

SmartShunt...will add a fused positive to the bank directly. When you add solar...you’ll want to add the temperature sensing wires...it’s a pair going to a single terminal..the fused line goes to Input 1 and the other (temp sense line) will go to input 2 of the Smart Shunt.

BMK...you’ll have to fashion a fused positive, and a negative. These both go directly to the batteries as well.

ME-BTS...the Magnum temp sensor get connected to a negative terminal directly on the batteries.

Now that I mention this...I don’t see the ME-BTS connected to your bank. We should check to be sure it’s connected. The inverter uses measured battery temperature to adjust the charge parameters. In cold weather it adjust the voltage up...I’m not weather it drops the voltage... This protocol is followed for Lead Acid chemistry...but not for LiFePO4 chemistry.

Ah, glad you added these! Thanks! I do believe the BTS is connected (third picture below). But I'm not sure what all the extra wires are for on the chassis batteries (first two pictures below). I'll need to do some tracing to see if I can figure out which ones connect to which device. But I see only that one "extra" small wire on the house batteries.

One more question: I noticed early on that there appeared to be some brown sludge on the undersides of each ventilation cap (last picture below; I already had cleaned off the one to the left when I took this picture but all 12 originally looked like the one to the right in this picture). When I went out and cleaned up the batteries, I wiped all these clean but then started wondering if I removed electrolytes that I should not have removed (although I can't imagine that the sludge would be a good thing inside the battery).

One more question: I noticed on some of these vent-cap contraptions (all three on each battery are connected together), there are two rubber gaskets on the outside/end caps but only one on the middle cap. (And I think one battery has only one gasket on each vent cap.) Is this by design? Or should they all have only one or should they all have two? (If the latter, I need to find some replacements. =)

Thoughts?

Oh, and one other note: when I went out to check for the BTS wire a few minutes back, I found that the nut on this negative connection was fairly loose (I think this cable is forced to twist to the side when the slide goes back in and so it works itself loose over time/multiple slide ins and outs like I've been doing the past two weeks and might also explain the bare copper strands that are protruding, now, from that cable). So note to anyone reading this thread, ALWAYS check that all connections are tight! I should've done that when I started out on this adventure but everything seemed snug enough when tugging on cables that I didn't actually touch what was then still very filthy hardware. =)

[twinboat]

You are supposed to remove the caps when equalizing.

[C.Martin]

As far as seals...I can’t imagine an owner adding rubber gaskets. I guess they could, but it wouldn’t have ever crossed my mind. My best guess is that someone at the factory was either trained to get a good fit...or asleep at the wheel...and accidentally put a gasket on the same one twice.

The joys of being a second owner. There are likely extra wires to trace...and only a 50/50 chance that they were factory installed. Could be a handyman add-on...or could be an accessory that Newmar added that wasn’t really close to the existing power buses.

The loose nut...yes, the torque on cables can loosen the nuts. They aren’t torqued incredibly tight to begin with. Newmar is really good on recent production. They zip tie the cables to anchor them to the batteries. This prevents any torquing at the actual terminal post. After you trace everything...and decide how you want to distribute the terminal connections...take them off and clean with scotch rite or steel wool...wipe them clean with isopropyl alcohol to remove any oils...reattach and torque the nuts...while aligning the cable with a proximity anchor point. Zip tie the cable to the anchor point. Then spray a little bit of battery terminal protector spray onto the connection. Dirty terminal connections will do more harm than a few inches of extra cable...

Some folks put mineral oil in the cells to try to keep the acid misting down. I actually ran an aftermarket product called Battery Demister in my batteries. It made a big difference in how much terminal maintenance I had to do once I added the stuff. I still added water regularly...but I found the terminals remained clean, so I wasn’t cleaning them again and again.

[BVJandJ63]

Originally Posted by twinboat

You are supposed to remove the caps when equalizing.

Yes, I did "remove" them (tipped them on an angle so they could vent. This sludge was already there from the first time I pulled the caps off to check fluid levels before I did anything else. Thanks for the tip, though!

[Solo_RV_Guy]

Originally Posted by TheTech

Yes separate issues in the sense that the GFI trips when the charging pad is plugged into this circuit. Like I stated above not all will do this. This is because the frequency can be off the 60hz enough to cause the failure. After moving a different pad with the same model to the circuit no other failures occurred. After doing some searching I found many other's having the same issues with this kind of charger. With all the work I do it's the first time I have ever run into it.

Usually it's a poorly filtered wall-wart power supply dumping harmonics (seeing 11th and 13th harmonics was new to me!) back up the neutral that causes GFCIs to trip.

The RF radiated by the charging pads is another matter, and probably won't affect most RVers.

[BVJandJ63]

Hi Power Gurus! I'm hoping I can pick your brains again. After a lot of research and careful consideration of all the input on this and other threads, I purchased a few items to upgrade my battery system but now I need to figure out what parts I need to perform the upgrade and any other tips that can help me complete these installs successfully the first time.

So I have the upgrade ME remote control (ARC), the Victron SmartShunt, and the ME-BMK. And while I install these things, I want to move all the cables off of the battery bank and onto a couple of terminal blocks and then run only one cable from each to the battery bank. (Knowing that there are still a couple of small wires that will need to connect directly to the batteries.)

But I'm having trouble figuring out what size cables to run between those blocks and the batteries and where to find the appropriate blocks, cables, and lugs so that I can connect both large and small cables to the blocks. Do folks typically build custom cables and blocks? Or is there a convenient place to purchase these items?

I also picked up a couple of Micro-Air soft start devices for the AC/heat pump units but I think I can handle that install (as long as I can get on and off the roof safely! =).

[C.Martin]

I use 4/0 cables for the single run to the batteries. This is actually the size recommended in my Inverters installation manual...but Newmar used 3/0 for the inverter.

There are plenty of prefabricated bus bars...

https://www.amazon.com/dp/B07P8CZZCG...p_mob_ap_share

Just look for amperage ratings. Some are quite low. I used one like that...but stacked the deck since I had some extra copper.

The HD switch allows me to cut + to the inverter before handling the - terminals to prevent damage to the ME-BMK and ME-AGS.

I cheated on the shunt...stacking. Not the best...I would go with another bus instead...but I ordered a longer metric brass bolt to enable the single connection point. It works, just more of a pain if you want to work on it. And you have to be careful that the terminals all lay flat to make a good amp carrying connection. I'll add a bus one of these days.

[twinboat]

You are not limited to one cable from the shunt to the batteries.

You can run parallel positive and negetive cables from the battery banks to the shunt.

I did that with an 8, 6 volt battery bank.

I used https://www.genuinedealz.com/product...de-by-the-foot

Well made cables and ends.

[Vickie 4369]

Shunt needs to see all negative current flow this is how mine is.

All battery negative connect to left bolt.

All negative for chassis, inverter and other, are on the right bolt.

[BVJandJ63]

Originally Posted by Vickie 4369

Shunt needs to see all negative current flow this is how mine is.

All battery negative connect to left bolt.

All negative for chassis, inverter and other, are on the right bolt.

Hi Ted:

Am I seeing your picture correctly? Is the shunt actually "floating" (or strapped but not bolted) on top of the battery bank, itself, as opposed to mounting the shunt to a compartment wall somewhere?