Originally Posted by JCamper
Along those lines does anyone know how many volts I should see coming into my batts while plugged into shore power? My meter shows 13.37 but that seems low.
I can no longer run my Maxx Air fan, 4 lights and a 600 watt inverter at the same time. I have 2 12v #24 batts and last trip the gens had to run an inordinate amount of time to recharge them. I suspect dying batteries but these are only 2 years old. (But are the dealer batts) any suggestions??
JCamp... you are seeing 13.3 as a Float voltage which means the batts have received 90+ to 100% of their charge. If you had just used them for a night...you should see a recharge Bulk voltage in the neighborhood of 14.5Volts for a few hours before it ramps down to float voltage.
You have a fan that takes maybe 4 amps at medium speed...a few bulbs and an inverter on standby which only uses a few amps...if your batts are going flat with that in short order they are really in bad shape.
Suggest you have murdered them by abuse since you don't appear to know much about them or have any way to monitor them.
Group 24 batts have about 75 amp hours each when new...a pair will have 150 amp hours OF WHICH YOU CAN USE 75 before recharging. If you don't know what you are using... and how much is left in your batts ... you end up killing them prematurely even if you're good about watering them.
Step one is to fully charge the batteries then pull the plug. Get a cheap turkey baster hydrometer at AutoZone and take a reading of EACH cell in EACH battery. My guess is you'll fine dead ones or close to dead...but at least you'll have the turkey baster for the future.
Assuming dead batts...IF you have room...get a couple of golf cart batteries at Sams or Costco...that will take you up to 220 amp hours or so which will give you 110AH before you need to recharge.
If you can't fit the golf cart batts...then get TRUE deep cycle 12V batteries ..not dual use... and get them in the largest sizes you can squeeze in...group 27 or 31 will give you slightly more or less than 200 amp hours compared to the group 24's ... but there's nothing wrong with 24's except your need to recharge more often.
If you want to avoid this situation in another 2 years... get one of these...
BMV-600S series - Victron Energy
They will pay for themselves easily in battery life.