Battery Maintenance Charger
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- PaulPSB
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Battery Maintenance Charger
Finally got around to buying one of these to prevent the battery on the 928 running down.
The instructions are fairly minimal but it says positive connection to positive terminal on battery and negative connection to car body.
Apologies for being ignorant but why doesn't the negative go to the negative terminal on the battery?
The instructions are fairly minimal but it says positive connection to positive terminal on battery and negative connection to car body.
Apologies for being ignorant but why doesn't the negative go to the negative terminal on the battery?
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- Brett928S2
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Re: Battery Maintenance Charger
Hi PAULPaulPSB wrote:Finally got around to buying one of these to prevent the battery on the 928 running down.
The instructions are fairly minimal but it says positive connection to positive terminal on battery and negative connection to car body.
Apologies for being ignorant but why doesn't the negative go to the negative terminal on the battery?
Yes you are correct. it makes no matter whether you connect it to the negative terminal OR a good earth on the body as both are the same circuit...personally i would connect to negative on the battery as you are assured of a good earth there...
OR....connect it to the jump start terminal under the bonnet and any engine earth...if its easier...
All the best Brett
928S2 AUTO V8 4.7 1986-XPIPES ANDERSON RACE EXHAUST,K&N, WIZARDS OF NOS MAXX RACE CONTROLLER & WON RACE REVO NITROUS KIT 2000 HP CAPABLE.
-UK 928 1/4 Mile and Top Speed Record Holder-208.10 mph- Email managingdirector@pchealthcare.co.uk
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- PaulPSB
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Re: Battery Maintenance Charger
Thanks Brett - I couldn't see any difference either.
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lindsayhbrown
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Re: Battery Maintenance Charger
i cut the croc clips off mine and hard-wired it to the battery using a tamiya remote control battery charger type two pin connector, no issues over the past 4 years or so
1986 911 Supersport in Silver (the new red).
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- tr7v8
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Re: Battery Maintenance Charger
Please make sure you have a fuse locally to the battery. Having told people time after time to do it & not doing it myself
Went to to the SELNK meet the other week. Paul & I smelt burning electrics & after squealing to a halt in the pub car park, found the lead to the solar panel smouldering & melting 
Jim
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lindsayhbrown
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Re: Battery Maintenance Charger
mine has inline fuse between charger and two pin connectortr7v8 wrote:Please make sure you have a fuse locally to the battery. Having told people time after time to do it & not doing it myselfWent to to the SELNK meet the other week. Paul & I smelt burning electrics & after squealing to a halt in the pub car park, found the lead to the solar panel smouldering & melting
1986 911 Supersport in Silver (the new red).
2023 Hyundai Tucson in dark grey.
2014 Mazda 2, ZOOM ZOOM, its the wifeys, honest !
2023 Hyundai Tucson in dark grey.
2014 Mazda 2, ZOOM ZOOM, its the wifeys, honest !
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stratfordshark
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Re: Battery Maintenance Charger
It's a safety thing Paul. When you complete the connection (if charger already plugged in) then there can be a spark.PaulPSB wrote:Finally got around to buying one of these to prevent the battery on the 928 running down.
The instructions are fairly minimal but it says positive connection to positive terminal on battery and negative connection to car body.
Apologies for being ignorant but why doesn't the negative go to the negative terminal on the battery?
The battery can vent hydrogen, so sparks in vicinity are not healthy!
928 S4 Amazon Green 91MY
- PaulPSB
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Re: Battery Maintenance Charger
Thanks folks 
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928GTSM
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Re: Battery Maintenance Charger
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- tr7v8
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Re: Battery Maintenance Charger
It will be fine on a car. If you have a Lidl supermarket locally their version is actually a C Tek copy but much cheaper.928GTSM wrote:Can anyone recommend a good battery charger for keeping the battery good when the car is not being used, on motorcycles I use an Optimate but I haven't checked if it's suitable for larger battery's that you have on a car.
Jim
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David924S
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Re: Battery Maintenance Charger
I have an Optimate I use for my motorbike and I have used it to recover the battery on my cars plenty of time with no problems but it does take time, however it will keep the battery charged over time.
David
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1991 Titan Grey 944S2 (sold)
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