New dual 6v's. Need some advice plz

[brianosaur]

So I just picked up two Interstate GC2 6v's from Costco for $94 ea.
The sticker states 210Ah@ 20hrs.
I dont plan on using them for about another month so I will just store them inside so they dont freeze.

I ran them in series on my workbench and get a charge of 12.35
So I assume this is at about 70% capacity?

I have a 40/120a car shop charger. Would it be ill advised to use this to top off the new batteries, or should I just hook them up to my TT and plug it into the house. The TT has a 3 stage converter/charger power center..

Kind of overwhelmed with battery service & maintenance as I go about reading about it. Going into only my second season with my new TT and the house battery from the dealer was a real poc that barely got me through last year.

I know I need to pick up a hydrometer and distilled water eventually.
Any tips would be great for a newb.

[deadticket8]

Thanks much for the info. I may have to go that way at some point, but for now I ordered a Pro Logix 2320 charger. $89.97 According to specs will go on float at 14.3 volts. That should allow me to run refrigerator(110v) at night along with fan etc. Well see how it goes!
Update: hooked up new charger and charged right up over 14 volts. Very happy! Thank you for educating me on trickle chargers.

[time2roll]

deadticket8 wrote:
Thanks for the info, but I do not have an RV. I used to though. Now I have a cargo trailer with a solar setup. I am looking for a good charger that can be plugged into a 2000 watt portable generator when I am parked in the shade. Need something that will top off batteries not stop charging at 12.5 or there abouts.

The linked converter will charge at 14.4 volts for 4 hours before it drops to 13.6 volts. There is also a manual override to go another 4 hours in boost mode.

Not high enough? There is a similar model that goes 14.8 volts to match the Trojan GC2 spec.

http://www.bestconverter.com/9200-148-Modified-Deck-Mount

Not fat enough? Get the 80 amp if you want more power.

That CTECH is fine too at 25 amps will take a bit longer.

[SoundGuy]

deadticket8 wrote:
Now I have a cargo trailer with a solar setup. I am looking for a good charger that can be plugged into a 2000 watt portable generator when I am parked in the shade.

CTEK Mulit US 25000. My 7 amp CTEK does do a proper 14.4 volt bulk charge. :B

[deadticket8]

Thanks for the info, but I do not have an RV. I used to though. Now I have a cargo trailer with a solar setup. I am looking for a good charger that can be plugged into a 2000 watt portable generator when I am parked in the shade. Need something that will top off batteries not stop charging at 12.5 or there abouts.

[time2roll]

deadticket8 wrote:
I camp from a cargo trailer now with solar panels. When I charge my batteries from my solar panels they show a charge of up to 14.4 volts. But if I charge batteries off of a trickle charger the highest they get is 12.4. Any suggestions on a charger I can use in shady spots that will take it up? Ill be charging from a 2000w generator.

http://www.bestconverter.com/PD-9260C-60-Amp-RV-Converter

[deadticket8]

I camp from a cargo trailer now with solar panels. When I charge my batteries from my solar panels they show a charge of up to 14.4 volts. But if I charge batteries off of a trickle charger the highest they get is 12.4. Any suggestions on a charger I can use in shady spots that will take it up? Ill be charging from a 2000w generator.

[time2roll]

Trailer is good to about 15.4 so just put the shop charger on and let it rip.

[ktmrfs]

pianotuna wrote:
You need to know what the battery maker says is the fully charged resting voltage. And that number is *only* correct at 25C (77 f).

As someone else said--a hydrometer is a far better way to measure state of charge.

If we assume that 12.72 is fully charged, then 12.65 is 99.4% of full. Unfortunately that last 0.6% means that the jar may well sulphate.

I'm not sure I'd say 12.65 is 0.6% from full. discharged a flood cell battery is around 11V, not 0.00V so dead to full charge is about 1.7V, and 0.07V is about 5%. so 12.65 V is around 95% SOC. the graph from 10% SOC to near 100% SOC is pretty linear with battery voltage.

and as you correctly point out just because fully charged voltage is XX.X 12.8 or whatever does NOT mean that charging a battery with a 12.8V charger will fully charge it. It Won't and will eventually lead to sulfation. Flooded cell batteries need a period of time with a voltage around 14.6V to fully charge and avoid sulfation. They need to stay at that 14.6ish volts until the charge current drops below a certain % of battery AH capacity. then they can drop down to a float voltage.

[pianotuna]

You need to know what the battery maker says is the fully charged resting voltage. And that number is *only* correct at 25C (77 f).

As someone else said--a hydrometer is a far better way to measure state of charge.

If we assume that 12.72 is fully charged, then 12.65 is 99.4% of full. Unfortunately that last 0.6% means that the jar may well sulphate.

[jkwilson]

brianosaur wrote:
Okay so after 24 hours of rest inside my house I got a series reading of 12.64v.

12.7v is full correct?

What should my new Costco Interstate's be reading so I know the difference between a bad charger and a bad newly manufactured 6-month-old battery?


I just put them in the garage and clipped the shop charger to them.
Charging now at 14.78v. All six cells are bubbling while charging, the trailing battery in the series was doing so a bit more so than the leading one. ...not sure if that matters.

To confirm what everyone is saying (and as previously posted) my WFCO converter was charging at 13.67v yesterday. Then I saw THIS sticker on the power center



We dry camped perhaps 10-12 nights last year on weekender trips.
Four or five trips ranging 4-7 nights at family resorts & screaming kids parks with electric.

Should I worry about the 3 stage WFCO when it's less than a dozen nights without shore power per year?

I am thinking before I spend $200 on a good 4 stage converter I will just throw the shop charger into the pickup bed and charge the batteries that way.

If I do should I flip the battery disconnect on the TT so 14.7v volts dont harm my trailer?

12.65V is full charge on most all flooded cell batteries. Trojans are 12.72V. Specific gravity is a better indication than OCV.

[ktmrfs]

brianosaur wrote:
Okay so after 24 hours of rest inside my house I got a series reading of 12.64v.

12.7v is full correct?

What should my new Costco Interstate's be reading so I know the difference between a bad charger and a bad newly manufactured 6-month-old battery?


I just put them in the garage and clipped the shop charger to them.
Charging now at 14.78v. All six cells are bubbling while charging, the trailing battery in the series was doing so a bit more so than the leading one. ...not sure if that matters.

To confirm what everyone is saying (and as previously posted) my WFCO converter was charging at 13.67v yesterday. Then I saw THIS sticker on the power center



We dry camped perhaps 10-12 nights last year on weekender trips.
Four or five trips ranging 4-7 nights at family resorts & screaming kids parks with electric.

Should I worry about the 3 stage WFCO when it's less than a dozen nights without shore power per year?

I am thinking before I spend $200 on a good 4 stage converter I will just throw the shop charger into the pickup bed and charge the batteries that way.

If I do should I flip the battery disconnect on the TT so 14.7v volts dont harm my trailer?

well, that label is not from the typical WFCO charger. While it could stuff 55A into a battery at 13.6V,if it was pretty deeply discharged. A good 3 stage will have around 13.6V at the output at max charge current on a deeply discharged battery. Then the voltage slowly rises to 14.6 or so as charge current drops and lets the voltage rise. Once it hits 14.7V or so and current drops to a low value you want the voltage to drop back to 13.2-13.6 as a float charge.

The more important fact is that it is only 13.6V max as I intepret it, you won't get a full charge, it won't rise to the 14.6 or so volts.

Now, if you do have another charger to get the full 14.7 V for bulk charging that will finish the charge. In reality when dry camping I and many others don't get the batteries to full charge every day etc. Get it to 85% or so. The time to get from 85ish% to full charge is pretty long and not really worth running the generator for. That's where solar helps.

then when we return home plug into shore power with my built in PD charger to get it finished charging. A few days won't hurt it, just don't leave it partially charged on return home.

you could flip the battery disconnect, but IMHO don't need to. A good built charger will go to 14.7V

[brianosaur]

Okay so after 24 hours of rest inside my house I got a series reading of 12.64v.

12.7v is full correct?

What should my new Costco Interstate's be reading so I know the difference between a bad charger and a bad newly manufactured 6-month-old battery?


I just put them in the garage and clipped the shop charger to them.
Charging now at 14.78v. All six cells are bubbling while charging, the trailing battery in the series was doing so a bit more so than the leading one. ...not sure if that matters.

To confirm what everyone is saying (and as previously posted) my WFCO converter was charging at 13.67v yesterday. Then I saw THIS sticker on the power center



We dry camped perhaps 10-12 nights last year on weekender trips.
Four or five trips ranging 4-7 nights at family resorts & screaming kids parks with electric.

Should I worry about the 3 stage WFCO when it's less than a dozen nights without shore power per year?

I am thinking before I spend $200 on a good 4 stage converter I will just throw the shop charger into the pickup bed and charge the batteries that way.

If I do should I flip the battery disconnect on the TT so 14.7v volts dont harm my trailer?

[ktmrfs]

brianosaur wrote:
Okay so in 2hrs on my TT converter, the batteries went from 12.35v to 12.83v. I flipped the battery kill switch and took a reading after a 10min cooldown.

While charging I got a start reading of 13.67v and it was at 13.55v after two hours.

Is that all good ....for a WFCO power center?

typical WFCO it is in float charge not going into bulk charge mode. And the float will NEVER get the battery fully charged, eventually leading to sulfation. A flooded cell needs time at 14.2-14.6V to get fully charged then drop back to 13.2-13.6 for float to keep it fully charged. And what you are seeing the the WFCO NOT going to the needed

[ktmrfs]

jjrbus wrote:
Is it just me? With a Progressive Dynamics 4 stage charger I rarely have to add water. So seldom I almost forget to check, which reminds me I should go look now.

similar experience. I check a couple of times/year may have to add a little. But if I never checked they would eventually go dry.