[Austelcom]

Have just changed over our 7P Touareg for a 2020 Adventure and needing to set it up again for towing our off road hybrid van.
My question is; has anyone here actually installed the 50A Anderson on their CR Treg, themselves?
just wondering if it would make more sense to run the 4 B&S cable to the battery, under the seat, or continue the cabling all the way through under the bonnet. Whilst connecting the ignition triggered isolation relay to an ignition point, somewhere?
Cheers;

 

[Wolfy]

Have just changed over our 7P Touareg for a 2020 Adventure and needing to set it up again for towing our off road hybrid van.
My question is; has anyone here actually installed the 50A Anderson on their CR Treg, themselves?
just wondering if it would make more sense to run the 4 B&S cable to the battery, under the seat, or continue the cabling all the way through under the bonnet. Whilst connecting the ignition triggered isolation relay to an ignition point, somewhere?
Cheers;

I've gone with a temporary solution given we don't use the van that much. Inside the battery box was plenty of room to install a 50A fuse, voltage sensing relay and a 6 B&S cable terminated with an Anderson plug long enough to come out of the battery box at the right front corner of the driver's seat. The battery box cover still closes properly. When we use the van, I plug in a suitable length of 6mm twin sheath and run it out the tailgate. The VSR works perfectly - with the van fridge connected, it powers continuously and then disconnects when the engine is stopped. Under 15A load, monitoring with a wattmeter at both ends, there is only about 0.3V drop back to the Anderson plug at the rear.

 

[Austelcom]

I've gone with a temporary solution given we don't use the van that much. Inside the battery box was plenty of room to install a 50A fuse, voltage sensing relay and a 6 B&S cable terminated with an Anderson plug long enough to come out of the battery box at the right front corner of the driver's seat. The battery box cover still closes properly. When we use the van, I plug in a suitable length of 6mm twin sheath and run it out the tailgate. The VSR works perfectly - with the van fridge connected, it powers continuously and then disconnects when the engine is stopped. Under 15A load, monitoring with a wattmeter at both ends, there is only about 0.3V drop back to the Anderson plug at the rear.

Thanks for the quick response.
Ahh, the battery is actually under the driver’s seat in the CR? Was under the passenger seat in our 7P. Would have been wondering where it got to. 🤣
So I assume I’ll need to remove a bit of trim to run the cabling through, but good to know that it’s feasible to connect to the battery under the seat And room for the isolating relay. Is there an ignition activated source under the seat for the relay?
I’ll need to install the Anderson permanently, next to the 12pin plug, as we typically travel 6 plus months of the year. Will also need to run a 4 B&S cable as we have a Redarc Alpha Manager 75 in the van so typically draw up to 45A from the car.

 

[Wolfy]

Not sure if there is an ignition switched source in the battery box. For my needs the voltage sensitive relay is all I need. It doesn't need an ignition switched source - it only connects the load when the alternator output exceeds 13.2V and disconnects within about 10 seconds of the engine stopping as battery voltage drops through 12.8V. So no current drawn with ignition on but engine stopped.

 

[Austelcom]

Not sure if there is an ignition switched source in the battery box. For my needs the voltage sensitive relay is all I need. It doesn't need an ignition switched source - it only connects the load when the alternator output exceeds 13.2V and disconnects within about 10 seconds of the engine stopping as battery voltage drops through 12.8V. So no current drawn with ignition on but engine stopped.

Ok. Thanks for that. Guess I’ll just need to have a look and see what I can find. A VSR wouldn’t be workable as the voltage can actually drop to as low as 12.5V (or less) whilst driving, so the charge from the car would be switching in and out. VSR’s aren’t really recommended for use with cars equipped with smart alternators, such as the CR.
Cheers;

 

[Malaudi]

Ok. Thanks for that. Guess I’ll just need to have a look and see what I can find. A VSR wouldn’t be workable as the voltage can actually drop to as low as 12.5V (or less) whilst driving, so the charge from the car would be switching in and out. VSR’s aren’t really recommended for use with cars equipped with smart alternators, such as the CR.
Cheers;

You can disable the fairly wild voltage swings by the smart alternator using VCDS. I found the system voltage varied from 15.5 when coasting (foot off accelerator) to just battery volts (about 12.2) when the engine under load. A fuel saving feature controlled by the ECU. With that feature disabled, the system voltage stays at 14.2 (depending on battery temperature) and is stable.

There is no switched power (+15 supply) in the battery box, under the driver's (RHD) floor. Only other way would be to locate a source of switched power in the fuse panel in passenger's footwell, (plenty there) and run a wire to a relay or contactor in the battery box.

 

[Austelcom]

Thanks for that clarification. Actually, I was surprised to find the battery under the floor in front of the driver‘s seat. So much easier to get to than being under the seat.
I’ll do some further investigation, but I’m thinking I may be able to also find an ignition switched source in the fuse box in the rear left luggage compartment. If that’s the case, I’ll place a relay in the back and run the 4B&S cable from the battery, to the rear relay and then on to the Anderson plug, which may be easier (TBC).
Cheers;

 

[Austelcom]

Just finalizing how I’ll run and connect the dc cable for the Anderson plug and I was gong to connect 6AWG cable directly to the battery under the floor, but then thought that maybe one should not connect directly to the battery earth, as I suspect that is monitored by the vehicles ECU, possibly via a shunt. Would that be correct? If so, one should never connect directly to the battery earth.
Also, whilst inspecting the battery connection, I noticed a plastic plug, residing under a small hatch, next to the battery on the floor.
Anyone have an idea as to what that may be?

 

[Malaudi]

You're correct in not connecting directly to the earth terminal of the battery for the reason you mention. Why not just connect the earth side of the Anderson plug to a nearby ground at the rear of the car?

The "plug" under the hatch near the battery is for manual release of the transmission from Park to Neutral. The handbook refers.