Battery Question

[Daddy_Bear]

I have just installed a 300W solar system and it works beautifully. So here's my question. I am hooked to shore power in my driveway. Noting in the RV is on/running but the fridge. By evening the Solar display/voltage monitor shows batteries at full charge of approx. 14.4V. When I go out around 7:00am the voltage has dropped down to 13.3V. Why is voltage in the batteries dropping when it is hooked to shore power?

Papa Bear

[westend]

Daddy Bear wrote:

red31 wrote:
could be WFCO and bad batteries, why the need for new batteries?

both wfco and controller can produce 14.4v, wfco for 4 hrs controller for 2, no info on how long either had been connected.

bad batteries can consume energy that goes to waste.

tinnitus, no, just noise

We bought the TH new in April, The batteries that came in it are group 24MF Centennials. I think I need more amp hours so that's why I was thinking 2 T-105's.

It's a worthwhile upgrade. There are those that think using 12 V batteries will save their bacon if one battery gives up the ghost. That's unarguable but failure of one Trojan 6V in a pair is a very rare occasion. I used to maintain a fleet of over 300 6V batteries (50 golf carts). Even with the ignorance of Golf Pros and missteps by the cart boys, we never had a single battery fail. After three years of improper use and charging, we did have a few 6 gang sets fail but that was to be expected from the misuse. After a charging network was installed and carts were plugged into the network, not a single battery failure nor golfer stranded in three years.
I gained a lot of respect for the Trojan T-105 in those six years.

[Daddy_Bear]

red31 wrote:
could be WFCO and bad batteries, why the need for new batteries?

both wfco and controller can produce 14.4v, wfco for 4 hrs controller for 2, no info on how long either had been connected.

bad batteries can consume energy that goes to waste.

tinnitus, no, just noise

We bought the TH new in April, The batteries that came in it are group 24MF Centennials. I think I need more amp hours so that's why I was thinking 2 T-105's.

[red31]

could be WFCO and bad batteries, why the need for new batteries?

both wfco and controller can produce 14.4v, wfco for 4 hrs controller for 2, no info on how long either had been connected.

bad batteries can consume energy that goes to waste.

tinnitus, no, just noise

[Almot]

westend wrote:
Hard to diagnose the 14.4V issue because we don't know if the converter kicks into absorption cycle when the solar charge is removed or if your batteries are seeing 14.4 all day.

That's it. Page 3 and counting.

Could be 14.4 all day because of wrong setpoints, could be slowly rising from 13 to 14.4 (slowly for many reasons), could be converter in Abs stage right at that moment. I mentioned all this several posts back.

The message that doesn't seem to get through is - VS30 is sophisticated enough to be able to set it up wrong.

VS30 is an off-brand - domestic Chinese brand, whatever. The closest big brand is Xantrex C35 for a few bucks more, practically same price, though display is extra.

T105 vs T125 - in my books, more AH is better. It's just 15 AH more. Get T125 if price difference isn't too big.

[westend]

Scrubber battery = A battery that can be used in a floor scrubbing machine. They have a taller height and provide more amp hours than typical GC2 Golf cart batteries.

Trojan makes a good battery. The 6V GC2 T-105 is the standard to which golf cart batteries are measured.

[MEXICOWANDERER]

My apologies MY BAD EYESIGHT
I read T-1275 which is a tall scrubber battery. My Bad (#2 for today)

Take the weight of each battery and divide by the cost you'll pay. That is the value ratio. Usually the addition of just a few amp hours is a waste of time. Golf cars have six 3 cell batteries. Motto: Dollars are made of pennies so in a large battery bank the increase is additive and justifiable.

[Daddy_Bear]

MEXICOWANDERER wrote:
Scrubber batteries have less CCA per pound than GC22's. If you aren't operating high amperage devices the scrubbers win for sake of durability. They have Trojan's best plate paste.

Sorry to be dumb here, but I have never heard of a Scrubber Battery. Is that a name brand? 6v or 12v?

[MEXICOWANDERER]

Scrubber batteries have less CCA per pound than GC22's. If you aren't operating high amperage devices the scrubbers win for sake of durability. They have Trojan's best plate paste.

[Daddy_Bear]

So, I'm thinking of installing just 2 Trojan T-105's (220Ah) or T- 125's (240Ah) batteries. Any advice for one over the other? Also, thanks for the input so far.

[westend]

Hard to diagnose the 14.4V issue because we don't know if the converter kicks into absorption cycle when the solar charge is removed or if your batteries are seeing 14.4 all day.

I'd suggest to look over the controller manual and make sure you have all the settings correct. Some controllers need to be manually set to achieve lower float voltage, not sure about yours.

As was stated above, Trojan 6V batteries like a higher voltage, 14.8V and above. Following the Mfg's suggested charging schedule will make sure you get the most longevity from the batteries. Good luck with your new system!

[red31]

Daddy Bear wrote:
I know the MPPT controllers are much better

during float, no way, absorption, not much. all these folks floating by noon waisted money and human nature causes them to bad mouth other's choices.

you did not provide enough info to diagnose you sit, every one is jumping to conclusions. no one knows which power supply was providing the 14.4v. New batteries, cuz the ole ones are bad?

carry on with your excellent controller. ignore the noise

[Daddy_Bear]

I don't have an inverter and the fridge is running on electricity. I don't mean to be a jerk myself but I would never tell someone that their equipment is CHEAP. There are no other items running on the batteries. I know there are still parasitic draws that are present all the time, radio light, CO/LP alarm, etc. I think I need to do more reading and learn how to operate the controller I have to it optimal capability.

[Daddy_Bear]

Theres lots of other words that folks can use to tell someone that what they spent hard earned money for is not the best one to have purchased. Could have just pointed out that its not the cost of the controller but that its the fact that its just a PWM 3 stage controller. I know the MPPT controllers are much better and somewhere down the road I will get one. But for now helping me by giving me advice on how I can use what I have to the best of its ability would be much better than telling me that I "still have a cheap 3 stage PWM controller".

[Almot]

Daddy Bear wrote:
...

I suggest you put more efforts in trying to understand what people here are telling.

Your controller is not keeping battery where it should be.
It is a cheap 3-stage, there are other that are more expensive, but it is still 3-stage. This means - you can and should adjust the parameters according to battery specs. Though running loads could still prevent it from charging the battery properly.