Upgrading and sussing out electrics.

[Phantom]

Since full-timing for over 2 months now I've been sussing out how best to improve my power generation and it's been a useful learning curve. We have a 120w solar panel and had a PWM regulator which wasn't very confidence inspiring and also found that the wire from the VSR was way undersize causing a fair voltage drop over the 7m length to the LB.
I toyed with the idea of increasing the solar panel size but as we are only light power users decided not to at the moment. But I did change the PWM regulator for a Victron Smart Solar 100/20 which can output up to 290w should I go for a larger solar panel sometime. I liked the idea of knowing how the system was performing via the Bluetooth app.

Also due to previously finding ourselves struggling to get any decent charge back into the leisure batteries I fitted a battery monitor to better know the SOC, but it's also handy to know how much power is going in or out. Whilst at it I also fitted the Inverter remote switch.

There's a three shelf cupboard in the moho garage and it had a battery on each of the two lower shelves until I moved them both onto the lower shelf, and made the shelf above removable for easy access.

Don't mention the mis-matched batteries, they'll match when next changed!

I was planning to upgrade the VSR cable size to 16mm2 to prevent the voltage drop then I thought of fitting a 30A B2B unit instead of using the VSR.
In anticipation and out of curiosity I've been sussing out what all the wires actually do that are connected to my leisure batteries. There's just one with a 2A fuse that I am unsure of, any ideas what might use such a low rating?
From the LB +ve there is a 6mm2 cable supplying the Electroblock via a 30A fuse. I decided to temporary remove the electroblock to see what connections were behind it.

I was quite surprised to find a 6mm2 cable from the starter battery and there is only a 0.01v voltage drop over the 7m length of it, there's also a 30A fuse at the starter battery end. I guess that the main purpose of this 6mm2 cable was for charging the starter battery via the original battery charger? But there is now a Zig X-70 connected directly to the LBs and a Battery Master that trickle charges the SB from them. So I guess I should be able to just connect the B2B between that and the LB, less than 1m away rather than adding a 7m run of 16mm2.

I removed a surplus cable from the far right two connectors (shown below), maybe it was for the original mains battery charger? Any ideas?

Unexpectedly I could not see how or where the solar regulator wires connect to the LB side, but will suss it out sometime.
It's good to have a better understanding of how it all works though.

 

[wildebus]

Looks nice and neat.

I have a suggestion for you which you might want to do now, but for sure at least when you update the batteries to be a matched pair...
You are not pulling the load equally from the batteries. It is hard to tell from the pictures but it looks like:
Inverter is connected to -ve on Right Battery (via Shunt) and +ve on Left Battery - that is fine
But seems all other loads are on the Shunt again on the Right and also the +ve on the Right - these really need to all be on the left +ve to balance across the pair of batteries.

Spare cable .... Blue/Brown on end - Black/Red the other? must be an AC/DC converter (seriously, looks like a cable that was knocked up quickly and definately (I hope!) not original, so who knows?!)

 

[Phantom]

Looks nice and neat.

I have a suggestion for you which you might want to do now, but for sure at least when you update the batteries to be a matched pair...
You are not pulling the load equally from the batteries. It is hard to tell from the pictures but it looks like:
Inverter is connected to -ve on Right Battery (via Shunt) and +ve on Left Battery - that is fine
But seems all other loads are on the Shunt again on the Right and also the +ve on the Right - these really need to all be on the left +ve to balance across the pair of batteries.

Spare cable .... Blue/Brown on end - Black/Red the other? must be an AC/DC converter (seriously, looks like a cable that was knocked up quickly and definately (I hope!) not original, so who knows?!)

Thanks, the inverter leads are as you said, all other loads are on right +ve and left -ve, so the opposite. The connecting battery -ve lead is 6" longer (with the extra 6" link) than the +ve so quite balanced I think. But guess I really ought to fit the shunt between the battery and ALL loads but just did it this way for convenience as was done on the roadside with no spare bits. I could probaly do with a terminal block of sorts for the small -ve wires but will see if I can do a workaround. I don't like those battery clamps at the back, they are awkward, I might change them.
The blue/brown wires are OE and larger than the rest. I've just remembered, I bet they once went to the top left connector on the Electroblock whatever that is for?

 

[wildebus]

Thanks, the inverter leads are as you said, all other loads are on right +ve and left -ve, so the opposite. The connecting battery -ve lead is 6" longer (with the extra 6" link) than the +ve so quite balanced I think. But guess I really ought to fit the shunt between the battery and ALL loads but just did it this way for convenience as was done on the roadside with no spare bits. I could probaly do with a terminal block of sorts for the small -ve wires but will see if I can do a workaround. I don't like those battery clamps at the back, they are awkward, I might change them.
The blue/brown wires are OE and larger than the rest. I've just remembered, I bet they once went to the top left connector on the Electroblock whatever that is for?

If you have the cables as described, then yes, batteries balanced but SOC meter will not be accurate and only give you inverter load data. Definitely worth changing at some time to get better info on battery bank.
I would be very surprised (and disappointed) if the black/red attached to the blue/brown was also original? Is that red bit at the end a connector? I wonder if not it if could be a temp sensor? (Ignore that. Just looked again and it is the red wire bent round and taped up)

 

[Nabsim]

Can’t believe how different yours is to mine, not even same model EBL. Your battery’s about 5 Mars further back than mine as well. You would think two same make vans would be similar huh lol

 

[Phantom]

I would be very surprised (and disappointed) if the black/red attached to the blue/brown was also original?

I'm now reasonably sure that the blue and brown wires would have originally connected the top left Electroblock plug to the far right two connectors on the block shown, and that someone has cut them at some time and attached the black/red for some purpose which has now become defunct.
I've just looked at the Electroblock wiring diagram and it seems that the wires were originally intended to feed a compressor fridge.

 

[Phantom]

Can’t believe how different yours is to mine, not even same model EBL. Your battery’s about 5 Mars further back than mine as well. You would think two same make vans would be similar huh, lol.

Mine is 2005 but think yours is a little later? I've noticed that there can be big revisions in just a year or two, like a taller fridge/freezer etc. I'm not keen on the Kenwood media centre, it's a PITA waiting for the screen to slide out and elevate, it still serves a purpose but much less than originally intended. I guess yours has a revised model?

 

[Millie Master]

@Phantom I might be wrong, but it doesn't look like your batteries have any kind of mechanically secure tie down to the van?

Phil

 

[Phantom]

@Phantom I might be wrong, but it doesn't look like your batteries have any kind of mechanically secure tie down to the van?

That's correct, they can only move if the moho was upside down, so would be the least of our worries.

 

[wildebus]

I'm now reasonably sure that the blue and brown wires would have originally connected the top left Electroblock plug to the far right two connectors on the block shown, and that someone has cut them at some time and attached the black/red for some purpose which has now become defunct.
I've just looked at the Electroblock wiring diagram and it seems that the wires were originally intended to feed a compressor fridge.

This is why (and I have made this comment before) it is not a very good idea to use flex for AC mains for DC circuits. Technically there is usually not a prroblem but oh, the confusion due to the colour coding when a new owner takes over the vehicle (or work is carries out and the original purpose of the cable is forgotten and assumptions made).

PS. If that cable was meant to feed a 12V Compressor fridge, it would be woefully undersized (so likely to have been used for that purpose by many 'professional' converters)

 

[SquirrellCook]

This is why (and I have made this comment before) it is not a very good idea to use flex for AC mains for DC circuits.

It's very common to find red and black sheathed electrical cable on commercial vehicles that have been repaired or altered.

 

[wildebus]

It's very common to find red and black sheathed electrical cable on commercial vehicles that have been repaired or altered.

For what purpose? DC Circuits? AC Circuits?

 

[SquirrellCook]

DC circuits, generally external where they want extra protection and tidier wiring.

 

[wildebus]

DC circuits, generally external where they want extra protection and tidier wiring.

well yes, Black and Red twin-core cable is pretty common for DC circuits and is 100% acceptable. No issues obviously.
You don't get people running Black & Red Twin cable for AC circuits though, do you? (bloody hope not!)

I am talking about buying and using reels of AC flex (i.e. Brown/Blue twin or Brown/Blue/Yel-Grn) for DC circuits. That is not a good idea as later on down the line, who knows when they look at it if its purpose is AC or DC?

 

[Phantom]

It doesn't help when people ignore the wire colours. Those wires that I removed - notice that the red is to blue, and black to brown. I also noticed that a blue was the positive and brown negative at my solar regulator to LB. Hmmn, there seems to be a theme here?

 

[Millie Master]

You shuld see the wiring in France, it's all arse about face!

 

[SquirrellCook]

It doesn't help when people ignore the wire colours. Those wires that I removed - notice that the red is to blue, and black to brown. I also noticed that a blue was the positive and brown negative at my solar regulator to LB. Hmmn, there seems to be a theme here?

Mercedes use brown as ground!

 

[Phantom]

Mercedes use brown as ground!

Well that may expIain the latter if the builders followed the same?

 

[wildebus]

Brown is standard vehicle ground throughout for both Mercedes and VW (don't recall about other makes).

I tend to use Brown and Black for ground lines, Yellow and Red for supply lines (use Yellow as it is used for radios as Perm +12V so logical to continue for extensions for radio power), and variety of colours for switched DC supplies,
Need to watch out for some US products though. The MaxxAir fan for example is pre-wired with a black and a white cable. White is for ground, which means ... yes.... Black is the +ve supply.

I HAVE used mains flex for a very specific DC purpose for a short time - 3 way lighting circuit wiring. But I did cover the Blue and Brown with coloured heatshrink to change the colours where it was outside the outer sheathing. But really not a great idea and not something I would recommend.

 

[wildebus]

Well that may expIain the latter if the builders followed the same?

I don't think you will find van builders commonly using twin core Blue/Brown for DC circuits. If they are they are idiots.