Trickle battery charge

I bought a computerised battery charger a long while ago and it has never worked. It has a mode switch on it and whenever I pressed it, the unit always remained on stand-by. Yesterday I was in my shed looking at it. It had been connected to the 12 volt battery for two weeks, and my voltmeter showed the battery was still only at about 4 volts. So I got out my old trusty analogue charger and connected it up and started charging the battery property. Then I started looking at the digital unit, and I was pretty frustrated. I think it cost me about $70, and it appeared to be money down the drain. I thought I'd give it a belt, so I connected it up to the terminals in parallel with the analogue unit and switched it on. The unit immediately sprang into life, went off standby started sensing and doing all the things it should do. So now it is charging the battery properly. When I was doing this I thought the smoke might escape and I'd be buggered - not so. This appeals to my sense of humour.

Some of those smart chargers won't start working unless the voltage is high enough. They're to smart for their own good.

DogT said:

Some of those smart chargers won't start working unless the voltage is high enough. They're to smart for their own good.

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Beat me to it. RTITFM :mrgreen:

Some are not ment to charge a flat or low voltage battery an can damage the battery by over charging it.
I found out the hard way when mine boiled a 2 week old battery completely turning it into a black mess.

I am going right now to check if the battery is hot - thanks for that. The charger is supposed to maintain a trickle charge after giving some strong bursts.

Have been very happy with my Optimate, A case of you get what you pay for here after buying a cheaper W-Mart item at first to be disappointed at performance. Saw that BMW shop had Opt. unit for winter storage bay so good enough by me.

Mine is an Optimate not some cheaper type it is one of the first type they sold and works fine but just don't use it on a flat battery. Having said that I only put battery on it for day or over night once in a while I don't believe you need to leave them on all the time. If you do it is time for new battery in my book.

True. BMW's have clocks that over a long time drain. So German to build in a clock.

We had a power outage here yesterday. When I checked the charger it had gone back to standby. The batter is still only showing about 7 volt (it was at 4 volt before I started charging). I think I will have to give it another belt with the analogue charger to get it going again. I like the thought of leaving the battery on trickle charge. I don't ride the bike often enough and sometime lose a battery through sulphate because it has stood there while it is flat.

acotrel said:

We had a power outage here yesterday. When I checked the charger it had gone back to standby. The batter is still only showing about 7 volt (it was at 4 volt before I started charging). I think I will have to give it another belt with the analogue charger to get it going again. I like the thought of leaving the battery on trickle charge. I don't ride the bike often enough and sometime lose a battery through sulphate because it has stood there while it is flat.

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AGM...

I have a bunch of Yuasa smart chargers. If you look around you can find them for about $20. They're only .75A but they do the trick, sock it with 15V to start then charge and go to trickle. You can leave it hooked up as long or little as you like. My Yuasa AGM is 3 years now and still holds 12.8V after a week sitting.

+1 on the AGM. Once tried, loyal forever. Motobatt also make chargers

http://www.probatteries.com.au/motobatt ... rgers.html