Battery Charging - Main Battery Chassis Point -

Dellmassive

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Battery Charging - Main Battery Earth Point -

so weve all be told NOT to bridge out the battery monitor on the neg side of the battery when charging it.

This is so the ECM can correctly gauge the SOC (state of charge) of the starter battery by monitoring the current flow in and out of the battery . . . . even when the van is sleeping.

20181228_141417.jpg

OK fine, no problem there . . . . . so my question to all is where are you picking up your chassis ground point? . . . . and one thats good enough to allow the 15amps charge that my charger is putting out?

20181228_141429.jpg

currently all i found was this small stud under the valence . . . . . but it seems a bit iffy . . . .

20181228_141423.jpg



no i also this question as the manual clearly states that you must use a chassis or engine block ground . . . . . but where is one? nearly everything is plastic and my lead is to short to reach down to the block.


20181228_141444.jpg


now as a comparison, our old BMW has the battery in the boot, it has a nice long chunky cable that runs along the under-body and up into the engine bay, to a nice convenient jump-point under a nice red plastic cover under the bonnet by the suspension turret . . . . . now right next to this point is a large chunky BOLT type thing bolted to the chassis for the purpose of a ground jump cable connection.

so has VW just not done anything about the NEG connection point?. . . . . or am i missing something?

why do you guys do?

EDIT: additional info,

Capture.JPG

.
12 Earth point, on left in engine compartment
q Specified torque: 9 Nm
13 Earth point, on right in engine compartment
q Specified torque: 9 Nm
15 Earth point, on cylinder head
q Specified torque: 9 Nm
607 Earth point, on left in plenum chamber
q Specified torque: 9 Nm
614 Earth point 2, on right in engine compartment
q Specified torque: 20 Nm
624 Earth point, starter battery
q Specified torque: 20 Nm
640 Earth point 2, left in engine compartment
q Specified torque: 9 Nm
642 Earth point for electronically controlled fan
q Specified torque: 9 Nm
714 Earth point on right of engine
q Specified torque: 20 Nm

.



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With such short leads I have used a bolt by lower corner of battery negative. However first time the bolt needs some twiddling – a few rounds out and in to break the paint for good electrical connection.
 
That`s great guys . . . . . any chance of a few pics of your solutions?
 
I've got a small charger primarily to maintain my batteries. Vehicle and leisure. It has a cold weather setting that sets it's output voltage at 14.7v. Current output is listed as 3.8 amps.

As its always live, even with ignition off, anyone know if this would cause any issue plugging this into the cigarette lighter socket, to maintain the battery charge?
 
I've got a small charger primarily to maintain my batteries. Vehicle and leisure. It has a cold weather setting that sets it's output voltage at 14.7v. Current output is listed as 3.8 amps.

As its always live, even with ignition off, anyone know if this would cause any issue plugging this into the cigarette lighter socket, to maintain the battery charge?
I've seen this done before without issues.

Though note that 10amps would be the max via the 12v sockets.

So a 3.8amp smart charger should be fine.

The lower dash is connected to the starter battery.

And the upper dash socket is connected to the leisure battery (if you had one fitted)
 
If you are leaving the tails permanently connected there is an earth point just inside the scuttle, you can probably see it through the grills in the plastic panel. Not easy to get to but it makes a good permanent solution.
 
I've got a small charger primarily to maintain my batteries. Vehicle and leisure. It has a cold weather setting that sets it's output voltage at 14.7v. Current output is listed as 3.8 amps.

As its always live, even with ignition off, anyone know if this would cause any issue plugging this into the cigarette lighter socket, to maintain the battery charge?
Not expecting any problems by charging through the cigarette lighter socket. The battery management of the van keeps track of currents in/out of the battery.
I would just check that the charger eventually enters into so called "float charge mode" - floating at about 13.5 Volts (instead of pushing at 14.7V). Most modern chargers are advertized to do this: float charge, trickle charge, etc.. Any link to spec sheet?
More to read --> https://batteryuniversity.com/learn/article/charging_the_lead_acid_battery
 
I think I might wire up a permanent connection to the leisure and starter batteries..

In the T5.1 we used the CTEK range of kit.

So a hardwired quick disconnect like this..

.
XXX9046_3_1.jpg

I like these as they are small, simple, and have a basic traffic light battery status on them.

But the Ctek charger is only 5amp.

So if I use the Noco... then I might need the anderson connector like this . . . .

.

140099.jpeg

.

Or just make my own Anderson connection that can be used for tempory Direct Solar MPPT connections while mobile/camping with my Renogy suitcase solar kits.

Andrerson_SB50_120A_double_pole_power_connector_red_16mm2_cable_1[2].jpg
 
Have you looked onboard chargers, for example: ChargerKit 2x12A • DEFA

Actually the part that might be of interest is the small Defa MiniPlug connector which can be easily located for example in front grill or bumber. Specified and certified to 250V/16Amps and the cable itself for installation even in engine bay. But shouldn't be used for 12V circuits as it's widely used for 230V and certified as such.

Installation examples and a few pictures of the connector https://www.defa.com/content/upload...information/Electrical-preheating/1920254.pdf and MiniPlug inlet cable • DEFA

To get an idea about the size, the hole diameter for Miniplug inlet connector is 24mm.

Although it’s a proprietary one it is very popular up here as EHU connector – thanks to the size. The main use is for engine preheating and onboard battery chargers.

Another company offering similar solutions including the connector is Start - Calix I’m afraid the products of these two companies are not interchangeable.

EDIT: A picture about my old T5 with a Defa EHU socket.
T5_Defa.jpg
 
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Not expecting any problems by charging through the cigarette lighter socket. The battery management of the van keeps track of currents in/out of the battery.
I would just check that the charger eventually enters into so called "float charge mode" - floating at about 13.5 Volts (instead of pushing at 14.7V). Most modern chargers are advertized to do this: float charge, trickle charge, etc.. Any link to spec sheet?
More to read --> https://batteryuniversity.com/learn/article/charging_the_lead_acid_battery

Had a wee look through the manual @mmi States it drops to trickle charge once it detects the battery is fully charged. Doesn't state what voltage it drops to however. Just states low current. I'll keep an eye on it and see what the voltage reading is when it's in trickle mode.
 
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Battery Charging - Main Battery Earth Point -

so weve all be told NOT to bridge out the battery monitor on the neg side of the battery when charging it.

This is so the ECM can correctly gauge the SOC (state of charge) of the starter battery by monitoring the current flow in and out of the battery . . . . even when the van is sleeping.

View attachment 34123

OK fine, no problem there . . . . . so my question to all is where are you picking up your chassis ground point? . . . . and one thats good enough to allow the 15amps charge that my charger is putting out?

View attachment 34125

currently all i found was this small stud under the valence . . . . . but it seems a bit iffy . . . .

View attachment 34124



no i also this question as the manual clearly states that you must use a chassis or engine block ground . . . . . but where is one? nearly everything is plastic and my lead is to short to reach down to the block.


View attachment 34126


now as a comparison, our old BMW has the battery in the boot, it has a nice long chunky cable that runs along the under-body and up into the engine bay, to a nice convenient jump-point under a nice red plastic cover under the bonnet by the suspension turret . . . . . now right next to this point is a large chunky BOLT type thing bolted to the chassis for the purpose of a ground jump cable connection.

so has VW just not done anything about the NEG connection point?. . . . . or am i missing something?

why do you guys do?

EDIT: additional info,

View attachment 36699

.
12 Earth point, on left in engine compartment
q Specified torque: 9 Nm
13 Earth point, on right in engine compartment
q Specified torque: 9 Nm
15 Earth point, on cylinder head
q Specified torque: 9 Nm
607 Earth point, on left in plenum chamber
q Specified torque: 9 Nm
614 Earth point 2, on right in engine compartment
q Specified torque: 20 Nm
624 Earth point, starter battery
q Specified torque: 20 Nm
640 Earth point 2, left in engine compartment
q Specified torque: 9 Nm
642 Earth point for electronically controlled fan
q Specified torque: 9 Nm
714 Earth point on right of engine
q Specified torque: 20 Nm

.

@Dellmassive - I recently connected a CTEK battery sense to my main starter battery, and as per the instructions in the box, I connected this to both the positive and negative side of the battery (and it seems to be working fine!)...however - I’ve just come across this thread. Have I therefore done the wrong thing? Should the negative be connected elsewhere?
 
@Dellmassive - I recently connected a CTEK battery sense to my main starter battery, and as per the instructions in the box, I connected this to both the positive and negative side of the battery (and it seems to be working fine!)...however - I’ve just come across this thread. Have I therefore done the wrong thing? Should the negative be connected elsewhere?

No not really, the Ctek draws only a couple of mA which in the grand scheme of things is like an extremely low draw and should not end up giving you battery problems.

The idea of the shunt is to monitor ALL of the power coming from/ leaving the battery. wiring the CTEK across the battery posts means that the Van Power management is not accounting for the tiny draw of power from it.. . . . . but its so low you should be ok... (provided your van is a daily-driver and not left parked up for days or weeks)

But if it keeps you awake at night . . . . . there is a body ground point just to the RHS of the battery that you can use as a ground.

ill dig out a pic.

its a light bracket bolt . . . . . but will work fine for that application.. just scratch off some of the black paint so there is a good electrical connection under the bolt-to-bracket join.


pics . . .

20190727_110736.jpg 20190727_110757.jpg
 
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That's super helpful - thanks @Dellmassive and @Loz. Given that it doesn't sound like it's going to cause me any issues - I reckon I'll just leave it across the battery! :) Cheers guys!

Whilst I'm writing... My Leisure battery is almost always reading 100% on my battery sense (charged from the CTEK D250SA) but the Starter battery seems to sit between 55% and 80% on the battery sense... Does that sound right?
 
That's super helpful - thanks @Dellmassive and @Loz. Given that it doesn't sound like it's going to cause me any issues - I reckon I'll just leave it across the battery! :) Cheers guys!

Whilst I'm writing... My Leisure battery is almost always reading 100% on my battery sense (charged from the CTEK D250SA) but the Starter battery seems to sit between 55% and 80% on the battery sense... Does that sound right?
yes, it does. Unless you add a smartpass to charge the starter battery as aswell.
 
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