Your suggested/best method for connecting a battery tender?
12-17-2014, 11:06 AM
#32
Burning Brakes
Thread Starter
Thoughts--
You really need a fuse in the charging cord positive conductor, near the jump post if you connect there, near the battery if you connect in the rear.
I've installed a pigtail in the front, connected to the jump post and adjacent ground point. The cable hides under the fender lip, and the connector sits under the front edge of the fender lip near the fan controller. It's out of the waay unless needed.
In the rear, there's a connection directly to battery positive and negative. Cord comes out of the battery well with the ground strap. and stores in the left side of the rear bumper until needed. To use it, the tool panel is moved forward a little, and the cable pulled out. Connected directly to the battery means it can charge while the ground strap is lifted. Static drain in my car is less than 20 milliamps, but still enough to cause the maintainer to cycle more than it should. The constant cycling is tough on the battery, so the ground strap gets lifted whenever the car will sit unused for more than a week or two. More than a month of sitting, and the maintainer is attached. The battery is vented outside the battery box using some plastic tubing through the positive cable grommet and down.
I have a couple versions of the Schumacher maintainer, including the flat one that Alan uses and the mini-brick that MartinSS displays on his windshield picture above. I added a CTEK 7002US to the collection this year, more in search of a 'smart' charger than a maintainer, and will use that during hibernation season. The connections for the CTEK include the cigarette-lighter adapter that 77Tony shows above, but that does no good for all but a few 928's; the lighter socket isn't powered unless the key is on. Instead, I adapted their direct-to-battery connection part by replacing the eyelet terminals with a specific Molex terminal I've standardized on for all the chargers/maintainers. So it plugs into any of the vehicles easily, no polarity concerns if I wire the connectors right the first time. Plus I made a set of various jumpers and extension cables using the same Molex style connector for maximum versatility.
You really need a fuse in the charging cord positive conductor, near the jump post if you connect there, near the battery if you connect in the rear.
I've installed a pigtail in the front, connected to the jump post and adjacent ground point. The cable hides under the fender lip, and the connector sits under the front edge of the fender lip near the fan controller. It's out of the waay unless needed.
In the rear, there's a connection directly to battery positive and negative. Cord comes out of the battery well with the ground strap. and stores in the left side of the rear bumper until needed. To use it, the tool panel is moved forward a little, and the cable pulled out. Connected directly to the battery means it can charge while the ground strap is lifted. Static drain in my car is less than 20 milliamps, but still enough to cause the maintainer to cycle more than it should. The constant cycling is tough on the battery, so the ground strap gets lifted whenever the car will sit unused for more than a week or two. More than a month of sitting, and the maintainer is attached. The battery is vented outside the battery box using some plastic tubing through the positive cable grommet and down.
I have a couple versions of the Schumacher maintainer, including the flat one that Alan uses and the mini-brick that MartinSS displays on his windshield picture above. I added a CTEK 7002US to the collection this year, more in search of a 'smart' charger than a maintainer, and will use that during hibernation season. The connections for the CTEK include the cigarette-lighter adapter that 77Tony shows above, but that does no good for all but a few 928's; the lighter socket isn't powered unless the key is on. Instead, I adapted their direct-to-battery connection part by replacing the eyelet terminals with a specific Molex terminal I've standardized on for all the chargers/maintainers. So it plugs into any of the vehicles easily, no polarity concerns if I wire the connectors right the first time. Plus I made a set of various jumpers and extension cables using the same Molex style connector for maximum versatility.
By the looks of this pic, you have your leads connected under hood at the positive terminal, but where do you connect the negative? Do you have addl. pics, please - thank you.
12-17-2014, 03:53 PM
#33
Chronic Tool Dropper
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There's a ground point immediately below and forward of the jump post there. Look through the plumbing for a small bolt that has a few brown wires connecting to the body there. 10mm head on a 6mm bolt, use a magntid nutdriver to remove. Clean all the surfaces with a small brass brush, and add the new connection to the stack under the bolt. Reassemble.
There's a small (10A) inline fuse in the positive lead from the jump post, tucked up out of site under the fender lip. Small (1/4") accordian tubing hides and protects the wiring, and there's a little bit of heatshrink where the wires go into the connector.
Sorry I don't have more pictures of the install details. I took that one to illustrate how stealthy the installation was done.
-----
Fast-forward to today. I have a couple of those Molex connectors on my craft table to fit up with the CTEK pigtails so they can plug into the various cars and toys. I generally don't use that front connector anymore, since I made the rear harness that connects 'around' the ground strap at the rear bulkhead at the tool panel. By the time I need to use the maintainer, I also want to disconnect the battery ground strap so it doesn't cycle the charging so much. The Schumacher maintainer wants the battery to stay between 13 and 14 volts, while the static voltage on the battery tends to bearound 12.5. Even my small 15-20mA parasitic draw pulls the voltage down pretty quickly from 14 to 13, cycling the maintainer (and the battery) again. I'm changing to a 'smarter' CTEK maintainer, and will watch the charging profil to see what it actually does in my car.
There's a small (10A) inline fuse in the positive lead from the jump post, tucked up out of site under the fender lip. Small (1/4") accordian tubing hides and protects the wiring, and there's a little bit of heatshrink where the wires go into the connector.
Sorry I don't have more pictures of the install details. I took that one to illustrate how stealthy the installation was done.
-----
Fast-forward to today. I have a couple of those Molex connectors on my craft table to fit up with the CTEK pigtails so they can plug into the various cars and toys. I generally don't use that front connector anymore, since I made the rear harness that connects 'around' the ground strap at the rear bulkhead at the tool panel. By the time I need to use the maintainer, I also want to disconnect the battery ground strap so it doesn't cycle the charging so much. The Schumacher maintainer wants the battery to stay between 13 and 14 volts, while the static voltage on the battery tends to bearound 12.5. Even my small 15-20mA parasitic draw pulls the voltage down pretty quickly from 14 to 13, cycling the maintainer (and the battery) again. I'm changing to a 'smarter' CTEK maintainer, and will watch the charging profil to see what it actually does in my car.
12-17-2014, 04:25 PM
#34
Burning Brakes
Thread Starter
Thank you - I'll take a look.
I am also interested in connecting in battery compartment, too, and running through the plugs in the recess. If anyone has pics of this, they'd be much appreciated, too. Thank you.
I am also interested in connecting in battery compartment, too, and running through the plugs in the recess. If anyone has pics of this, they'd be much appreciated, too. Thank you.
12-18-2014, 12:03 AM
#37
Mine is connected directly to the battery, with the end of the connector coming out of the hole at the bottom of the battery box , through a rubber grommet I picked up at lowes. The head of the connector just sticks out the hole.... very easy to connect / disconnect to the tender.
12-18-2014, 11:10 PM
#38
Chronic Tool Dropper
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There's not a lot to it really. I found a fused power leads setup at a flea market years ago, with 10ga wiring for something big. You can find similar pieces intended to supply aux audio amplifiers. Eye terminals on the battery end, fuse in the positive lead right by the battery positive post. At the other end, I placed one of my 'standard' 2-pin 0.093" Molex connectors (same type you see in the front apron picture), with enough length to run out of the battery box into the tool tray area parallel with the ground strap. I leave a foot of the wiring coiled up behind the tool tray. Unlatch the tools and slide forward far enough to snake the coiled end out. Connect charger. The cable runs out with the hatch propped on the latch a little. With the cover on the car, the charger can sit outside the cover on the rear wing, so I can see the diagnostic lights on the charger.
12-20-2014, 01:36 PM
#39
Chronic Tool Dropper
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Rear Charger Harness
Here's a couple shots of the rear harness plug by the tool tray. With the tool tray in place, no exposed connectors. As you can see, it comes up out of the battery well with the ground strap. I 'included' the wiring in a second shrink layer around the ground strap where it passes under the battery door lip and goes by the spare wheel.
12-20-2014, 01:43 PM
#40
Chronic Tool Dropper
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The CTEK ring-terminal adapter has a 2-pin Molex-type connector added here so it mates with the harness that lives in the car. The ring terminal adapter, with no modifications at all, is a perfect option for those who want to use the jump post in front. There are three flashing LED's on the adapter that show state-of-charge even when the charger/maintainer isn't connected.
I bought the larger CTEK US 7002 for its extra charging current when used as a standard charger. The smaller units are just as good in the maintainer mode, and plug in to the same CTEK adapter harness.
Hope this helps!
I bought the larger CTEK US 7002 for its extra charging current when used as a standard charger. The smaller units are just as good in the maintainer mode, and plug in to the same CTEK adapter harness.
Hope this helps!
12-20-2014, 01:49 PM
#41
Chronic Tool Dropper
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I should note that the CTEK US 7002 charger came with one eyelet-terminal adapter, and with standard charging clamp adapters in the package, so no need to buy extrat pieces if you are only permanently wiring one car. I didn't know that so I ended up with an extra adapter. They aren't expensive, and I'll find a use for it I'm sure.
12-23-2014, 07:48 PM
#42
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I'm looking to upgrade my charger and I'm thinking about getting a 'Noco Genius Wicked Smart' charger. Looking at either a model G1100 or G3500. It seems to be pretty trick. Anybody use one of those yet?
01-04-2015, 04:01 PM
#43
I got myself a BatteryMinder 1510 which comes with ring terminals. There's discussion in this thread about connecting to the jump post. Before I do something stupid I have to ask - is the jump post threaded such that it can be unscrewed?
Hugo
Hugo
01-04-2015, 06:42 PM
#44
Electron Wrangler
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Alan