Which converter is best for 4 Trojan House Batteries?

[TangoDancers]

We plan on putting replacing our two Costco golf cart "house" batteries with 4 Trojan T105-Plus batteries. We know this will require an upgrade to our converter but we need help recommending the appropriate one (and appropriate AMPS).

From our research and recommendations it seems like Intelli-Power is the way to go so that's what we plan to purchase (unless persuaded otherwise). Assuming Intelli-Power is appropriate we need to decide which one (60-AMPS, 70-AMPS or 80-AMPS) for the above batteries.

One RV technician tells me that the Intelli-Power 9260 is more than enough AMPS and that any more AMPS is overkill and requires a completely different electrical connection that will complicate installation.

Any advise on this configuration would be greatly appreciated (in lay terms please -- we are novices in this field).

Thank you!
Susie

[davecampbell]

"We know this will require an upgrade to our converter"

and

"Assuming Intelli-Power is appropriate we need to decide which one (60-AMPS, 70-AMPS or 80-AMPS) for the above batteries. "

the two questions are not related. There is no reason the "converter" (there is no such thing as a "converter" its a DC power supply or an inverter, anything that changes the type of power is a converter, the word "converter" is not sufficient) will not work with one, or 100 batteries. Its a question of how LONG it will run till the batteries need recharged.

The "which power supply or inverter" is about the LOADS, not the batteries. Will the present unit power everything needed and is it just a question of battery life between charges? If so, just change/add batteries. If more power is needed to run more things, its required to also look at the wiring and fuse panels to make sure they can handle it without overheating.

2.) Dont buy these second-rate, no name / remanufactured batteries. Buy Exide. Better quality, life and current capacity

3.) The correct way to specify the system is:

a.) determine the total load current needed. "Load" is lights, motors etc that work from the power converter. That is what determines the amperage needed. I just put in a 13V, 68 amp unit in an Alfa which can draw, absolute max, everything turned on at once (extremely unlikely to impossible) 130A. The average, day to day draw is probably more like 30-40.

b.) determine an average power draw, just add up what is normally used, and for how long till recharge. Those two factors determine the battery bank capacity in amp-hours (AH) (how many amps x how many hours drawn). 30 amps of load x 4 hours per day x 3 days = 30 x (4x3) = 360 AH.

c.) divide the AH figure by the the individual battery A-H capacity (maybe 250 per battery) to determine the number of batteries needed. If 360 AH, divided by 250AH per battery, 360 / 250 = 2 batteries.

d.) divide the AH figure by the percentage of efficiency for the so-called "converter" (AC inverter, 85% efficient, switching power supply, 85-95%, transformer power supply, 50% efficient on a good day). 360 AH/ 0.85 for an inverter = 423 AH / 250 AH/battery - 2 batteries.

then make ABSOLUTELY SURE TO PREVENT FIRES that the wiring can handle any changes. Good time to replace the battery cables.

[garym114]

Whew -
The max charging rate of deep cycle, wet cell batteries is 1/10 of their capacity. If the batteries are 225 amp hours the max charging rate is 22.5 amps. The 80 amp will charge each at 20 amps during the bulk charge mode which would be OK. 60 amps would charge each at 15 amps. If the batteries were discharged to 50% each would need about 112.5 amps put back in. The converter rating in amps is just a time thing. All three will work and be OK for your battery bank size. It will just take longer with the 60 amp converter. The higher rated one will do the job quicker.
Loads make no difference. You are trying to size the converter to your batteries. It is my understanding the Intellipower 9200 series are very good converters.

[TangoDancers]

Thanks Gary and Dave... for your wealth of information. It's a lot for me to digest, but I do understand several of your points. Just for clarification, we were planning to replace the converter/charger, which is separate from our inverter. So far, I think we will consider the 80amp IntelliPower as our first choice.

Many thanks,
Susie

[wa8yxm]

There is no "Best" thought there is a "Best Class" First, You need a good 3-stage converter, Some of the more or less outstanding converters (That is better than best) are the Progressive Dynamics 9180 with charge wizard, or the 9200 (Which has the wizard built in) the outstanding feature is the automatic "Equalization" feature, after 20 hours of "Float" it switches to like 15 minutes of "Equalization" to prevent sulfation and stratification.

Another outstanding converter is the charger side of the Xantrex Prosine 2.0 inverter/converter. The optional advanced feature here is remote temperature sensing and compensation. It will automatically adjust charge voltages based on Temperature at the battery box.. It is also adjustable current wise up to 100 amps.

I present these only as examples however.. NOT by any means the only units in the highly recommended/best/outstanding category.

Next we need to talk about the size of the converter.

Xantrex, for flooded wet cells, recommends a fastest charge of 30% capacity, or in your case 132 amps. Trojan, on the other hand 10% (or 44 amps) I'd go with something in between, say 80 amps.

[rogueii]

I have used the Xantrex Pro-sine 2000 watt for 6.5 years, on 4 Trojan T-105's. It has worked well--post in the Gallery at
Copy_of_RV_Inverter_Wiring_004 - iRV2.com RV Photo Gallery

[Don_Monaco]

WOW! I just took a course in stupid. How does one learn all this? I have an 08 Monaco Monarch 35'. I dry camped this weekend and went to start the generator on the second day and it just clicked. I tried a few times and then waited and tried again. Bingo it started. I noticed the battery connectors have some corrosion and plan to clean the terminals this weekend. That said this is an 08 and barreries probably need to be replaced. Or there is a problem with the generator. Wish you lived next door. Batteries are Interstate U2200. After reading just a little I think I should go with stock replacement. Then nothing else needs to be changed. Can you comment.

Thanks,
Don

[rogueii]

Don--There are a lot of solutions out there, all with different personal preferences. Try to attend some Ralleys that are taliking about the RV electronics. Question a lot of campers, about their experience.
I have found, that the Trojan T-105 "Wet Cell" will give me about 6 to 7 years of good performance. It is important to use the system, and keep the batteries charged. Don't let them run down. Be sure to keep the WATER topped off. This will ruin the cells if they go dry.

Check the Solar sites on the internet and read the info they supply. Trojan Battery had some good knowledge base a few years ago.


Best og luck

[wa8yxm]

First, it may not require an upgrade, depending on what you have not, Magnetek 6300, Parallex 7200, (no "T") yes, upgrade, Iota with IQ4, Don't bother.

I will say this though, the Progressive Intella Power WITH charge wizard, either built in (9200 and others) or plugged in optional (9100) is hard (impossible) to beat, I might add the IQ-4 (IOTA) is also hard to beat (Roughly equivlent) which is why I said don't bother.

The next question is how big: Depends on who you listen to.

Two pair - 440 amp hour and per Xantrx the max recharge rate sholud be no more than around 30 percent of that or 132 amps I don't think they make 'em that big so the biggest you can get.

ON the other hand Trojan suggests for best battery life charge much slower (and longer) say 44 amps.

My recommendation is 60-70 amps, that's one pair on the Xantrex scale (just in cuss you loose one)