Diamond Dog

Just watched this video
It says to always jumpstart and to never hook up battery chargers to the negative battery terminal and instead use the negative grounding post by the driver's side of the car.

I have a Ctek trickle charger. Do you think this applies to it? I use the quick connect adapter and the positive terminal and the grounding post are too far apart to reach. I have been using the charger for about a year and nothing seems to be wrong with hooking it to the negative bettery post but who knows?

Are trickle chargers exempt from the process as outlined in the video?

Rich_Jenkins

For jump starting, the goal is to avoid a spark above batteries which emit combustible gas (oxygen, hydrogen).

While a concern, I would not worry too much myself about a properly attached trickle charger. However ymmv. If your personal safety evaluation leaves you uncomfortable with that, you could easily construct a pigtail to reach the negative post on the other side of the frunk bay.

Diamond Dog

Thanks. The video seemed to communicate concerns with damaging the battery or electronics and not so much a spark and fire concern. I was more looking to address that concern (damaging battery and or electronics)

Rich_Jenkins

For which? Charging a car via a trickle charger? Or jump starting?

Diamond Dog

trickle charging

Rich_Jenkins

Same answer, Electrically, there’s zero potential across the battery negative and the ground at the lug that Porsche provides for jump starting. You can prove this yourself by putting a meter across both to verify 0 impedance.

Connecting a trickle charger in the range of 1 to 4A is a purely mechanical thing, If you find it inconvenient or impossible to attach the lugs on the CTEK pigtail across the frunk, you’ll need to build a small black negative cable extension, or just use the 12V outlet. My CTEK, however, would not work anyway, since the M6 posts / threads on the Porsche battery terminals were smaller than the lugs CTEK supplied on their pigtail. (I’ve since bought a GOCO Genius 1A and have it directly connected to the battery. Mainly because my CTEK failed, and I could never get them to respond re warranty coverage.)

Hope that helps.

Bxstr

I always use the 12v plug inside the car to charge with the CTEK. That is easiest. I have seen both ways done with the battery terminals for direct connecting. I think most attach both to the battery, but as mentioned if you want to do it the safest way, I would put the ground on an actual grounding point on the car and not the battery.

Southbranch

To avoid any concerns about explosion and/or electronics damage, I connect my trickle charger to a wire that has its positive side on the battery cable and negative side on the strut tower, because the wire won't reach to the official grounding post. I use extra nuts of the correct thread for each connection.

Diamond Dog

Sorry I am so stupid. I know you told me how to do this and how to hook up the negative lead of the ctek trickl charger to the grounding post. So should I assume that you are staing i SHOULD do it this way? If it isn't a big deal I rather not, but the video got me concerned. I know not to.jump the car or to use a regular charger by connecting to battery post, but am wondering if a trickle charger is different?

I wasnt clear from your response

Rich_Jenkins

No worries. I'm just some random guy on the internet. You should do what you feel comfortable with. For folks who aren't sure, following the manufacturer's recommendations is never a bad idea.

FOR JUMP STARTING THE CAR

This procedure should be in your operating manual. I would follow the steps there that Porsche recommends whenever jump starting a car. It's always positive first, then negative. Reverse when disconnecting. In case of a jump start, I absolutely would ground the dead car jumper cable at the provided negative post right side of the frunk, as per the Porsche User Manual.





FOR CHARGING THE BATTERY

If you have a CTEK charger, I suggest you follow the instructions in the manual for using it to charge your car. I don't know which CTEK you have, but I had a CTEK 3300, so let's assume that one. Here is the page out of the manual:



Your options here are the Clamp, the Eyelet (says M6, but mine wasn't) or optional 12V accessory plug. I would use any of those that worked. No, I would not necessarily ground the charger at the frunk jump start ground point, because the device we are using employs low current (1A at the low end of typical chargers (e.g. NOCO Genius 1) and 4A at the higher end (e.g. CTEK), but that's just me. Because my battery is in decent shape, and is not in need of frequent deep charges requiring high current, I opted to use a 1A charger. This results in a smaller unit and less heat emission in my closed space (garage) over the larger 4A CTEK unit (and of course not to rag on the CTEK, but it failed and I wasn't going to buy another one.)

If the optional 12V socket works for you, that's probably easiest. My 991.2 seems to charge on either the under-glove box outlet, or the smoker's package 12V center console outlet. I've seen other folks indicate their outlet shuts off after a brief time. Mine never seems to do that. I'm not sure why.

But since I'm not driving my car a lot these days, I permanently affixed via the M6 studs the GOCO pigtail to my battery terminals, leading the cable up and out to near the passenger side windscreen wiper. It sits there. When I want to charge, I open the car, plug in the outlet, turn on the GOCO, close the car, lock it, and let it sit. I typically leave a 12V Voltmeter plugged into the smokers 12V outlet, so I can monitor the charging voltage. It ranges from a high of 12.9V (I think, don't quote me) when on charge down to sitting for days reading 12.3 or 12.4. Occasionally it turns on, again, reading 12.9V while charging. (below is a pic of my install, just prior to me putting in some zip ties to nail everything in place).




Bottom line, you have to do what you think it right and best for your car. I wouldn't suggest my way is the best, it just is the best for me.