jimdillard

Greetings to all! I'm a new member of this forum and I'm seeking some technical advice please.

I purchased a NOCO Genius 5 Smart Battery Charger for my 2019 911 Turbo S (991.2). I'd like to hardwire a quick disconnect battery charger cable to the installed AGM battery terminals. The Porsche Owners Manual recommends for charging, that the POSITIVE (+) lead of the battery charger be connected directly to the battery POSITVE (+) terminal, and the negative lead of the battery charger be connected to the NEGATIVE (-) CHASSIS POST located about 28" away from the battery.

If instead I connect the NEGATIVE (-) battery charger lead directly to the NEGATIVE (-) battery terminal will I cause damage to the vehicle's electrical system? Are there downfalls associated with doing this I'm not aware of? I've always done the "direct connect" method to both battery terminals with no issues for the many motorcycles I've owned. But this isn't a motorcycle we're talking and I have zero desire to re-live painful lessons others have already learned. I'm all ears accordingly.

Thank you very much for your assistance.

Jim

B Russ

My 17 991 is connected to the battery without issue. I believe a 5 amp or lower charger will not cause any problems.

Rich_Jenkins

I leave my NOCO 1 charger connected directly to the positive and negative battery terminals, no issues.



My belief is that historically the rational for a separate ‘negative’ ground/earth chassis is if, when connection takes place in a jump start scenario, any arcs that occur, don’t occur over the top of a lead acid battery potentially off-gassing oxygen and hydrogen. No bueno. Hence a physically separate ground.

jimdillard

Thank you. The NOCO Genius 5 is a 5-Amp unit.

jimdillard

Thanks Rich. I wondered if this might be Porsche's concern. The good news is that most of these "smart" units are now equipped with reverse polarity protection. No more dangerous arcing.