My bus has been off the road for a while, so I checked the batteries for charge. My leisure battery was dead flat, only reading 0.7v. As my shiny modern electronic battery charger won't charge a battery on less than 7.7v, I hooked it up to my very analog 35 year old charger overnight, with the intention of hooking up the modern charger/conditioner once it got the voltage up. Clearly having a senior moment, I connected the old charger the wrong way round, and have now managed to reverse the polarity of the battery. Doh! It's now showing a healthy 12.7v the wrong way round. I've googled it, and apparently it's only possible to reverse the polarity under very specific conditions, which were exactly as described above. Question is, what do I do now? I only run a small inverter off it for charging phones, so it's no great loss. Can I just switch the wires round on my split charge and inverter and roll with it? Or should I run it dead flat again and hook up my old charger the right way round this time. It would be a shame to bin it. Sent from my ONEPLUS A6013 using Tapatalk
Its probably sulphated up as you let it get that flat. Only a small part of it is likely to be working. See what happens when you connect a brake light bulb to it, a drain of about 2 amps. It will probably fade out in an hour or two. You should also not see the battery voltage jump significantly between light connected and disconnected. A healthy battery might drop 0.02 volts with that tail light bulb. Much more than that and its a Norwegian Blue. As you use an inverter rather than 12 volt to 5 volt switchmode converters, your charging setup is fairly heavy on battery because it is less efficient, the loss in the inverter is added to the mains chargers losses, so that brake light bulb is representative. If you have a proper battery tester, use that.. But really .. bew battery time..
As Mikesjames says it’s not great running inverters for small loads such as phones You are changing 12 volts dc to 230 volt ac with the inverter efficiency and then dropping down from 230vac to to 5 volts again with the phone charger efficiency. best to go dc to dc Good luck with the battery
Nice faux pas but the battery is goosed , not by your tomfoolery but it won't hold charge - trust me , been there , done that . Once it's reached a certain low point voltage wise that's it , it'll show 12 volts but won't hold it for more than a few hours . Sent from my SM-G960F using Tapatalk
Yes, the leisure battery in Lizzie Lu was like that when I bought her and I swapped it for a new one. Like you, I charged it with an old school battery charger and it just about managed to blow up the grandkids' paddling pool. No need for it now as the George the dog bit the side out of the pool...
Cheers guys. The inverter was originally to power a small fridge, that's gone and I've ended up using it just for plug in chargers. Not very efficient I agree. Sent from my ONEPLUS A6013 using Tapatalk
Good move ditching the inverter , do you really need a leisure battery ?? If it's only used for charging phones etc the main battery will be more than adequate through a fag lighter and usb adapter... Sent from my SM-G960F using Tapatalk
I`d be as bold as to say if you`re just powering lights , music (no amp!) and charging the odd ipad or phone you don`t need a leisure battery - i had 20 years without one and only fitted one to power the Propex from then on it was a slippery slope - compressor fridge etc etc ...
I have a leisure battery, a massive, heavy lead-acid thing shoehorned into the left rear quarter, and the wiring to the split relay is bit suspicious (if you can't tell, I'm suspicious of all wiring, even the stuff coming from the factory ). I thought it was powering LED lights (the original interior lights are nowhere to be found), a car stereo in the side cabinet, and some USB sockets in the glovebox. Yesterday I found out the USB sockets are wired to the car battery - I had the glovebox out, so I disconnected the leisure battery, only to find the terminals were still live I don't think I'll bother keeping it installed just to run some LED lights, it's not worth the potential issues.
Previous Owner had one installed, but no idea what it powered, it had crocodile clips at the battery, so ripped the wiring out and didn't waste any time in fault finding, and started again, just to ensure that the starting battery doesn't get drained unnecessarily, was doing wiring anyway so no hassle. Everyone's different that's the good thing about owners!
My split charge prevents the starting battery from discharging while using the leisure battery. However, it doesn't work the other way, as I discovered when my son left the stereo on, with the volume down, while parked on the drive, and it flattened both batteries. (The stereo is connected to the starting battery). Oh how I laughed! Sent from my ONEPLUS A6013 using Tapatalk
