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Topic: Setting up a Xantrex Charger/Inverter (Read 386 times) previous topic - next topic

Setting up a Xantrex Charger/Inverter

I am trying to figure out the setting I should use on my Xantrex Charger/Inverter for amp/hour capacity. I have three 8G8D batteries wired in parallel. On the battery spec sheet, is says: Capacity at C/100 = 265 Ah, Capacity at C/20 = 225 Ah, Capacity at C/5 = 188 Ah. Now I now to find the total capacity of all three batteries I add up the capacity of each battery. So, do I add up the C/100 of each battery to get 795 Ah and use that number for the setting on the Xantrex? If not, could you please explain what I should use for the correct number. Thanks in advance.
Bob
Bob & Kathy
2007 Nimbus
Full Timers
Retired Charter Bus Owner/Operator

Re: Setting up a Xantrex Charger/Inverter

Reply #1 –
Bob
What model Xantrex do you have?
Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: Setting up a Xantrex Charger/Inverter

Reply #2 –
Quote from: prfleming –
Bob
What model Xantrex do you have?

That would be a Xantrex Freedom 458 Series  - 20, Inverter/Charger. Thanks
Bob & Kathy
2007 Nimbus
Full Timers
Retired Charter Bus Owner/Operator

Re: Setting up a Xantrex Charger/Inverter

Reply #3 –
C/20 is the number that is used to describe what is commonly called amp/hours (ah).  You would have 675 ah between the 3 batteries which you get by adding the three C/20s together. 
Robert
Build # 5304
1998 34' U270 Cummins 6CTA8.3

Re: Setting up a Xantrex Charger/Inverter

Reply #4 –
Quote from: rsihnhold –
C/20 is the number that is used to describe what is commonly called amp/hours (ah).  You would have 675 ah between the 3 batteries which you get by adding the three C/20s together. 

Thanks - that is interesting. What exactly does the C/20 stand for? Would it be 20 percent? I would have never thought of using the number. I have now the original batteries in service and the unit was set for 440Ah. Interesting that Foretravel set it for that number and not 675. Again, thanks for the info.
Bob
Bob & Kathy
2007 Nimbus
Full Timers
Retired Charter Bus Owner/Operator

Re: Setting up a Xantrex Charger/Inverter

Reply #5 –


mine is set for 130 amp bulk charge rate with three mk 8g8d's

A 458 may only charge at 100 although. 

Roughly twenty percent of the rated amp hour capacity is a widely accepted bulk charge rate.

Matches the 160 amp alternator that Foretravel fit on my 97.

Power loss through the cables from the alternator to the isolator then to the batteries probably results in 130 at the batteries.

My two cents

Newer chargers have battery temp sensors to adjust the charge rate to match the temp of the battery at the cable
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4
 

Re: Setting up a Xantrex Charger/Inverter

Reply #7 –
Quote from: rsihnhold –
Why Does a Battery Have a C5, C20 and C100 AH Rating? Can't They Make Up...

I'll just provide you a link as it'll do a much better job of explaining it that I can but C/20 is the batteries discharge over 20 hours, which is the most commonly used number.

Thanks! Great article - Now I understand why the C20. Again, thanks
Bob
Bob & Kathy
2007 Nimbus
Full Timers
Retired Charter Bus Owner/Operator