Returning to AC

[MickYork]

Yes you're right. I have a "modern" charger and if a battery is completely flat it won't charge. I also have a "traditional" charger that works fine on completely dead batteries.

[dickie]

My oxford optimate can recover from very low voltages but if the battery is completely wrecked, it can't fix that.

If it's gone flat due to leaving lights on for example, it will fix it. If on the other hand, it has been neglected for months, like my triumph has, it won't fix it.

To my embarrassment as an electrical engineer,I don't really understand battery technology, I just know that this is how they behave.

[Meds]

Finally got round to checking and it was a dodgy earth from the rectifier.?

Good news- try fitting the battery and running it to see if the battery will charge.
You loose nothing by giving it a go

[coaster]

Ive read somewhere that you can fool modern inteligent chargers by connecting in parallel with a good battery, not tried it myself yet but will give it go over the next few days

[Scooterlam]

Ive read somewhere that you can fool modern inteligent chargers by connecting in parallel with a good battery, not tried it myself yet but will give it go over the next few days

Spot on coaster.
Done it many a time.
Also if you have a clever one with repair feature
You can use the pulse feature to drag the battery back to a point when you can switch to the usual charge setting.

[coaster]

Ive read somewhere that you can fool modern inteligent chargers by connecting in parallel with a good battery, not tried it myself yet but will give it go over the next few days

Well, the battery on my Marcos was flat and wouldnt take a charge or respond to the 'reconditioning' setting on my charger. So thought I'd try connection the 5 Amph battery off my LiS. Unfortunately that wouldnt take a charge either but it did respond to the reconditioning process. After about 8 hours the scooter battery was showing 13.5 volts so I connected it in parallel with the car battery which dragged the voltage down BUT the reconditioning cycle was now able to work. Left that on for a few hours and disconnected the scooter battery and left the car battery to charge normally overnight and this morning it read 145.2 volts...result

[Warkton Tornado No.1]

this morning it read 145.2 volts...result

Does this mean our energy crisis is over?

[Fast n Furious]

At 145.2V it probably means it's a hybrid.

[coaster]

At 145.2V it probably means it's a hybrid.

That should be 14.2 volts, it needs the flux capacitor to be charged to get up to 142 volts

[Bilko]

this morning it read 145.2 volts...result

Does this mean our energy crisis is over?

Brilliant!