Electrical Gotta love Jayco's "wiring"

Macca_75

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Aug 3, 2016
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#1
Not sure what came out of the factory and what was done at the dealer pre-delivery (I could take a guess based on what is in a loom and what is not). Post picking the van up I have had 1 additional loom added (Gas heater).

The only reason I poked my head in there was I dropped a second battery in and need to connect it.

The van was order "pre-wired with provisions for 2 batteries, but only supply 1".

This is what it looks like at the moment.

1579749229622.png


I dropped it off at the Auto Elec's (same one that does my car). Not sure I had the time or inclination to try and sort this out. I guess I could have just connected the second battery, but by dropping it off I am hoping I have a much neater result.
 

Macca_75

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Aug 3, 2016
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#3
Here's what the finished product looks like. I also had a dual USB fitted near the front bed for charging phones.

20200123_171146.jpg


All fuses were put into a 8way fuse box and the shunt was also related and fixed to the wall. Much neater - I should of got this done when the van was new. There is always next time.
 

mikerezny

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Sep 11, 2016
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#4
Hi,
Nice neat job. There may be a future for you at Jayco!

If you want to ensure both batteries are charged and discharged evenly, it might be worth considering to wire the batteries so that all the +ve inputs and outputs are on one battery and all the -ve inputs and outputs are on the other battery.

cheers
Mike
 

mikerezny

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Sep 11, 2016
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#6
I didn't do it - the autoelec did

But yes the feeds are split across the batteries so +ve off one and -ve off the other.

At least now if something goes pop on the road I have a chance of fault finding.
Hi,
from what I can see, there are two wires on the bottom -ve terminal and at least three on the top -ve terminal.

I would have expected all wires to be on the bottom -ve terminal.
cheers
Mike
 
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Drover

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Nov 7, 2013
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#7
Thats a lot better and as you said you can find things now and also it will operate better...... While we can't see the cables fully it should be wired up like this pic otherwise when your charging one battery won't get to a full charge and one will do all the work....

..... All your +ve (POS as us plebs say) should be off the terminal with the red arrow and all your -ve (Neg) off the one showing the earth symbol any cables off the other battery terminals other than the connector will only confuse the system............. If its like the pic below then the one piggy backing won't be doing much.....

 

Macca_75

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Aug 3, 2016
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#8
This is what I asked for (and I am sure has been done). I'll check the actual routes tonight but I am confident it will be right - the guys know their stuff and do great work.

I know the negative has a shunt (for the Drifter panel) and there are also 3 things by-passing the shunt (I know the gas heater is one, I suspect the breakaway may be another). This will probably explains what @mikerezny 's keen eye saw in the pics. The by passed items could be on either item.

I'll be adding the Victron battery sense directly to one of the batteries as well in a few days (bypassing the shunt again).
 
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Drover

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#9
Was a bit hard to tell in the pic and like Mike I was wondering about the extra cable........Thing is extra connections should really run off a buss bar not off the batteries, battery cable runs to buss bar and everything else comes off the bar or HD fuse box, if for some reason something needs to connect direct to battery then it should draw from both of them, namely from the POS to van terminal and the NEG to body terminal, the terminals connecting the batteries should only have the jumper lead nothing else............ That is a hard and fast rule for optimum performance and long battery life.

Breakaway shouldn't be connected to the house battery..... The battery sense should be across both batteries........ Looking at nice tidy wiring is a bit like watching the chooks feed, a great pleasure to view........
 

Macca_75

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Aug 3, 2016
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#10
Was a bit hard to tell in the pic and like Mike I was wondering about the extra cable........Thing is extra connections should really run off a buss bar not off the batteries, battery cable runs to buss bar and everything else comes off the bar or HD fuse box, if for some reason something needs to connect direct to battery then it should draw from both of them, namely from the POS to van terminal and the NEG to body terminal, the terminals connecting the batteries should only have the jumper lead nothing else............ That is a hard and fast rule for optimum performance and long battery life.

Breakaway shouldn't be connected to the house battery..... The battery sense should be across both batteries........ Looking at nice tidy wiring is a bit like watching the chooks feed, a great pleasure to view........
**I have an admission to make - I love tech and toys**

The Battery sense *could* be across both batteries HOWEVER you physically mount the module on the (a) battery as it has an inbuilt temperature sensor that is uses in conjunction with the voltage to figure out the *ideal* voltage required. This is passed back to each MPPT controller that is part of the network, which in turn allows the MPPT controllers to calcualte the difference between their output (at the controller) and the input (at the battery). The controller can then boost the output to ensure the ideal input goes into the battery. Anyway - I waffle - here is something Victron created for your viewing pleasure


the point of my rant - I can only physically mount it one 1 battery so I may as well take the voltage of that battery as well

And this was one of the reasons I order another controller for the portable blanket - to make sure I am making the most of the sun :)

I agree about the bus bar - it would have been ideal however it's probably the last 1% and I can live with it. Maybe next time, maybe if I get bored one weekend. It would be easy to do anyway now it's so neat. I will confirm what the cables are (now you have my mind going) so at least i understand what is and what is not.
 
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mikerezny

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#11
Hi,
In some ways it matters not however you wire the inputs and outputs. If you wire it in the accepted way, the batteries will be charged and discharged evenly and that will result in better utilisation of the system and more even aging of both batteries. This should result in a longer life for the batteries.

The issue is that there is a small voltage drop across the connecting cables. Not much of an issue if they are wired with thick cables and the maximum current in and out is small. The voltage difference is more significant when the current flow is large and the connecting cables are small.

Put a 2000W inverter in the system drawing 200A from the batteries and, if wired incorrectly, one battery will carry most of the load, the second battery will be less loaded. Then when the inverter is switched off, the idling battery now will have to recharge the drained battery to restore equilibrium.
Similarly when large charge currents are put into the battery, one battery will reach full charge before the other has reached full charge. It will take some time before both batteries will be fully charged.

Quite often, people wire them incorrectly stating the input and output currents are so small and thus it doesn't matter. Then, much later, a large inverter is installed and the initial assumptions don't apply. One battery get a hiding, and if it fails, it is not really known how much the incorrect wiring had in the premature failure. Then, since one fails, they buy 2 new batteries.

If you wire the battery sensor and all other wiring as per the accepted way (+ve on one battery, -ve on the other), both batteries will be charged and discharged evenly, therefore they should both be at the same temperature so it won't really matter at all which battery the box is mounted on to sense the temperature.

cheers
Mike
 
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Boots in Action

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Mar 13, 2017
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#12
**I have an admission to make - I love tech and toys**

The Battery sense *could* be across both batteries HOWEVER you physically mount the module on the (a) battery as it has an inbuilt temperature sensor that is uses in conjunction with the voltage to figure out the *ideal* voltage required. This is passed back to each MPPT controller that is part of the network, which in turn allows the MPPT controllers to calcualte the difference between their output (at the controller) and the input (at the battery). The controller can then boost the output to ensure the ideal input goes into the battery. Anyway - I waffle - here is something Victron created for your viewing pleasure


the point of my rant - I can only physically mount it one 1 battery so I may as well take the voltage of that battery as well

And this was one of the reasons I order another controller for the portable blanket - to make sure I am making the most of the sun :)

I agree about the bus bar - it would have been ideal however it's probably the last 1% and I can live with it. Maybe next time, maybe if I get bored one weekend. It would be easy to do anyway now it's so neat. I will confirm what the cables are (now you have my mind going) so at least i understand what is and what is not.
Hi @Macca_75, A very high tech piece of electrical equipment "Battery sense". Although my MPPT charger is nowhere near as high tech or high cost, I do not have to do the fancy phone connection to an app. My MPPT charger has a line attached to a thermistor which I have taped to the top of my battery. This measures battery temp all the time and the controller adjusts the charging voltage accordingly automatically. Voltage and battery temperature are also displayed all the time too on my screen. Much simpler for a non tech guy like me! But good luck to you and your new technological toys.
 

Macca_75

Well-Known Member
Aug 3, 2016
571
478
63
44
SE Suburbs, Vic.
#13
Hi,
from what I can see, there are two wires on the bottom -ve terminal and at least three on the top -ve terminal.

I would have expected all wires to be on the bottom -ve terminal.
cheers
Mike
All good @mikerezny . I quickly followed it through today. The bottom battery -ve has 2 connections - 1 to connect the batteries and the other to the shunt (so nearly all negatives are coming off this terminal). The bottom +ve has 1 connection to the top battery.

The top battery +ve has 1 connection from the bottom battery, 1 to a fused box (for all workloads going through the shunt) and and 2 more connections that bypass the shunt (and line up with the -ve of that battery). The bypassed workloads are the fan for the gas heater and the breakaway unit. The battery override on the Drifter panel isolates all other workloads (and I don't want these 2 to be isolated for any reason). I guess they could have run the by passed workload negatives to the other battery, but it's pretty neat this way. I'm comfortable not monitoring the usage by these 2 workloads as a trade off of them never being disabled.

Any inverter (if I add one in the future) will go through the shunt and therefore both batteries anyway. The cable they used is a pretty decent thickness and not all insulation either. I have a 1000W in the back of the car so use that for now anyway.

Real test is when we get away next weekend - weather pending I'll drain the crap out of the batteries and top them back up.

@Drover - yeah I love gadgets even if I don't know how to drive them - gives me something to learn. The battery sense also measures the voltage at the battery and communicates back to all the MPPT controllers so they can calculate and losses and adjust accordingly. Probably only going to come into it's own when using the Kings cheap Anderson extension leads on the solar blanket :)
 
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