hermanmullins Report post Posted December 28, 2017 Lots of items in the coach think it is funny and giggle going down the highways and they sometime jiggle loose to. I had a loose ground in my Inverter and it was so bad that I took it out and had it bench tested and it was fine. I thought my ground felt a bit loose when i took it out. Made sure all was very tight when I reinstalled it no problems since. Herman Share this post Link to post Share on other sites
bburns8 Report post Posted December 30, 2017 On 12/28/2017 at 5:09 PM, DickandLois said: Would the sound still be coming from the transformer even when I turned off the inverter and charger? YES, The reason is AC power is going into the unit from either the line directly or through the 30 amp breaker in the power panel. There should be no buzz when not connected to shore power or when the circuit breaker feeding the unit is off. Do check the ground copper wire to the unit is tight as well as the ground points / connections at the breaker box and the chassis frame. That should not change things, but it is always good the check them - things just giggle loose driving down the road. Rich. Thank you Rich. Share this post Link to post Share on other sites
bburns8 Report post Posted December 30, 2017 Any ideas what might cause the 12.25v reading I'm getting on my house batteries (new batteries, new battery cables, voltage tested in series) when unplugged from shore power, Inverter ON, Charger ON and no load? Share this post Link to post Share on other sites
manholt Report post Posted December 30, 2017 It's almost at rest, there are gremlins still drawing some wattage, including inverter. A fully charged battery is about 12.6 when just sitting there supplying the little computers and micro chips that you can't shut off. Share this post Link to post Share on other sites
hermanmullins Report post Posted December 30, 2017 One thing people forget is the radio. Even when the radio is off the memory card is still drawing so as to not loose the clock and presets. Herman Share this post Link to post Share on other sites
richard5933 Report post Posted December 30, 2017 Check the manual for your inverter. If it's turned on, even with no load, odds are it's still drawing power from the batteries. The manual should show what the at-rest current draw is. Share this post Link to post Share on other sites
five Report post Posted December 31, 2017 16 hours ago, richard5933 said: Check the manual for your inverter. If it's turned on, even with no load, odds are it's still drawing power from the batteries. The manual should show what the at-rest current draw is. If it's a Magnum, it is drawing a little power. That's why I keep mine off unless using it. Share this post Link to post Share on other sites
dickandlois Report post Posted December 31, 2017 Five, I installed a new sine wave inverter and the only way to stop all the power draw is to install a disconnect switch at the battery, but that resets the unit to factory defaults. The other issue is the initial high current surge when the power is reapplied. So I just let it draw a few mil. amps. A small solar panel or trickle charger covers that and One needs to remember that the chassis, ECM, TCM and other modules are also drawing a small current. Disconnecting the Chassis battery places the ECM into a relearning mode and the system will fail an emission test until driven around 100 miles. Doing that legally could be a challenge or a paper chase in many states. Rich. Share this post Link to post Share on other sites
dickandlois Report post Posted December 31, 2017 How long does the voltage stay at 12.02 volts? Does it continue to drop? I have run into a case where 1 of the cells of a relatively new battery had just water in it. No lie. And if memory is correct, that battery would read real close to the readings you are getting. A battery hydrometer is the only way to test the cells for this type of problem. One bad cell on a 6 volt battery would drop the voltage by about 2.08 volts. A 12 volt battery with one cell with a water reading would drop by 2.08 Volts. You have a o.72 voltage drop. That kind of reading would indicate to me that the water to acid mix in one of the cells could be off by around 50 %. I do not know the acid to water mix percentage, but I will see what I can find regarding that number ! Rich. Back to the chemistry book(s) Battery acid is sulfuric acid that has been diluted with water to attain a 37% concentration level. Share this post Link to post Share on other sites
manholt Report post Posted January 1, 2018 FIVE. I never turn either one of my 2 magnums off ! Share this post Link to post Share on other sites
five Report post Posted January 1, 2018 During my inverter issue about 18 months ago, I had several discussions with the techs at Magnum. Bottom line, it makes no difference whether on or off, other than it draws some power when on, even if not actually inverting. Share this post Link to post Share on other sites
manholt Report post Posted January 1, 2018 FIVE. Welcome to 2018. I remember your problems, thankfully I have not had any gremlins in my Magnums, just bad batteries problems and now have AGM's again! Just does not draw enough to concern me and now I have 50A. at all of Linda and my sticks and brick's! Share this post Link to post Share on other sites