Charger / Inverter Question

[gbanker]

At present I have a Mastervolt Mass Combi 12/2000-100 (120V) combination charger/inverter. THe Mastervolt recommendation for this unit is that it is for battery banks of 200 -600 AH. My battery bank is 800AH and when charging I see a quick dropoff to a charge rate of 50 - 60 amps. Not good as I often need to recharge 150 -200 AHs into my battery bank.
So, should I replace this unit with the 12/4000- 200 (120V) unit, parallel a second 12/200-100 unit or is there another approach? Thanks

[CharlieJ]

gbanker-You are going to have to provide more information in order for us to sort this out. Specifically; what is the chemistry and age of your house bank and how are you monitoring the bank usage and replenishment?

Charlie

[djmarchand]

I am not sure that another charger would do you any good. I had an 800 amphour bank that was supported by a 2000 watt Freedom inverter/charger which has a DC charging capacity of 100 amps.

With the batteries 1/4 discharged I would start the genset to supply power to the charger. It would charge at 100 amps for 10 minutes, 80 for 15-30 minutes and then drop to 50 or so for the next hour.

Unfortunately the charging algorithms built in to these devices are conservative to avoid damaging the batteries.

David

[btrayfors]

gbanker:

Agree with CharlieJ....we really can't help you until we know the answers to his questions.

But, it's highly unlikely that a larger or a second charger is needed.

Bill

[gbanker]

djmarchand: you have the same issue as I do. So will paralleling a second 100 amp charger to increase the charging capacity to 200 amps be the way to go or should I replace with a 12/4000-200 that has a 200amp charging capability?
CharlyJ: batteries are Sonnenschein which I believe are gell.
btrayfors: guess I did not explain my issue clearly. If I have a battery bank on 800AH and I can only charge at 50 - 60 amps wouldn't a higher capacity battery charger be the way to go? I have to believe that a 800AH bank can absorb more than 50 - 60 amps an hour. Thanks guys

[CharlieJ]

Specifically; what is the chemistry and age of your house bank and how are you monitoring the bank usage and replenishment?

So far so good:

Chemistry = gel
Battery age = ??
Method of monitoring bank usage and replenishment = ??

Charlie

[Zanshin]

Remember as well that if you upgrade to more charging amperage you might have to run new cables. Do you know what gauge cable you currently have and how long the run is? When I upgraded from my standard 80amp to 120amp charger (plus inverter) I had to replace all the cables between the 880Ah battery bank and charger/inverter.