Help choosing the right converter/charger?
Hi My TT has a Parallax 7345 converter. For the past year I have been using 550 watts of Solar and a MPPT controller charging my batteries. We have a 12V system at the moment. And I am using (4) 6V...
Forum Discussion
I guess the OP is done, so it is ok to address Roy's concerns.
"I have been using three each GP24 85AH batteries and I have found my total demand from the batteries when first starting my 14.4VDC Boost charge will demand right at 52-53AMPS DC when first hit with 14.4VDC when they are at the the appx 50% charge state....
I see this 53ADC Current for about 15 minutes and then it starts tapering back and in an hours time it will be down to around 8AMPS DC Current demand."
1. There is no such thing as "demand." There is "acceptance." In fact, 220 AH or so worth of battery bank will easily accept well over 70 amps of initial charging.
The 53 amps you see is just the "60 amp" PD converter being its usual lame self in not being able to do its rated amps, and in addition not being able to maintain them at a constant level for the entire bulk stage. Too bad , so sad, it is what it is. Think of it as a 55 amper, being optimistic.
2. 15 minutes before tapering is a sure sign you do need new batteries, which is happening , so that is the good part! (55 amper on a 255AH bank (3 x 85 )with a 55 amper would be at constant 55 for about an hour before batteries reached Vabs and started to taper the amps)
3. Your new bank of four 6s (440AH) will easily take 150 amps or so of initial charging, so there is no sweat about the 60 amper. With just the 2000w generator, which would struggle to run a 75 amper, you should keep the 60 amper. Only get more amps worth of charging for less gen time if you happen to get a bigger size of generator.
You are stuck with a longer gen running time with the 60 amper, but it could be more cost effective than buying a bigger gen and a bigger amp charger, as long as the campground will let you keep running the generator. ( ISTR that is an issue where Roy camps, same as it is here in the provincial parks)
BTW a 50-90 on 440AH will take about 4 hrs and 40 minutes with a 55 amper (Roy's 60 doing what it does)
"I have been using three each GP24 85AH batteries and I have found my total demand from the batteries when first starting my 14.4VDC Boost charge will demand right at 52-53AMPS DC when first hit with 14.4VDC when they are at the the appx 50% charge state....
I see this 53ADC Current for about 15 minutes and then it starts tapering back and in an hours time it will be down to around 8AMPS DC Current demand."
1. There is no such thing as "demand." There is "acceptance." In fact, 220 AH or so worth of battery bank will easily accept well over 70 amps of initial charging.
The 53 amps you see is just the "60 amp" PD converter being its usual lame self in not being able to do its rated amps, and in addition not being able to maintain them at a constant level for the entire bulk stage. Too bad , so sad, it is what it is. Think of it as a 55 amper, being optimistic.
2. 15 minutes before tapering is a sure sign you do need new batteries, which is happening , so that is the good part! (55 amper on a 255AH bank (3 x 85 )with a 55 amper would be at constant 55 for about an hour before batteries reached Vabs and started to taper the amps)
3. Your new bank of four 6s (440AH) will easily take 150 amps or so of initial charging, so there is no sweat about the 60 amper. With just the 2000w generator, which would struggle to run a 75 amper, you should keep the 60 amper. Only get more amps worth of charging for less gen time if you happen to get a bigger size of generator.
You are stuck with a longer gen running time with the 60 amper, but it could be more cost effective than buying a bigger gen and a bigger amp charger, as long as the campground will let you keep running the generator. ( ISTR that is an issue where Roy camps, same as it is here in the provincial parks)
BTW a 50-90 on 440AH will take about 4 hrs and 40 minutes with a 55 amper (Roy's 60 doing what it does)
