kimenker Report post Posted March 18, 2019 When I've got my 2008 Journey plugged into my 50 amp service the batteries don't seem to charge any higher than 12.8 when I check the reader on the wall of the coach. When the engine or generator is running (as it is running) it reads 14.1, what can I do to increase the charge other than connect a charger/maintainer? Share this post Link to post Share on other sites
wolfe10 Report post Posted March 18, 2019 kimenker, Welcome to the FMCA Forum. Which battery bank (chassis or house) reads 12.8 VDC when on shore power? What does the other battery bank read? Some coaches only charge the house bank from shore power, others charger both banks. Also, what converter, charger or inverter charger do you have. The "smart" ones need to be properly programmed for : battery technology (wet cell, AGM or Gel), battery bank size (amp hrs @ 12 VDC) and also ambient temperature unless you have the optional temperature probe on the battery. Share this post Link to post Share on other sites
richard5933 Report post Posted March 18, 2019 Do I understand that the same charger is showing different outputs depending on whether you're plugged into shore power or on generator? Share this post Link to post Share on other sites
kimenker Report post Posted March 18, 2019 Thank you! Both the chassis and house read the same. The type of inverter/charger is Airpax Dimensions 2000 watt inverter and 100 amps, transfer rating 30 amps. There is a Electrical Management System w/smart surge protection above the inverter. I also have a Automatic Line/Generator Switch Model ATS 501 (Not sure what this does either). Share this post Link to post Share on other sites
wolfe10 Report post Posted March 18, 2019 As Richard suggested, voltage and inverter/charger output should be EXACTLY the same on generator or shore power. The inverter/charger has no way of knowing what the source of external 120 VAC is (nor world it care)-- 120 VAC=120VAC. I have no first hand experience with an Airpax inverter/charger. Have you properly programmed it? Per this manual float voltage for wet cell batteries is 13.2 VDC. Higher for sealed batteries: https://www.rvtechlibrary.com/electrical/dimensions_owners.pdf If it is properly programmed, next thing I would do is have the batteries fully charged and then load tested. Share this post Link to post Share on other sites
kimenker Report post Posted March 18, 2019 wolfe10 thanks for your help. Share this post Link to post Share on other sites
