My full electrics upgrade project with a long inverter cable run

[8balladdict]

Posting this thread to document my upgrade from AGM to Lithium, which includes the install of a whole lot of extras and a long cable run to a 2Kw inverter.

It's been an equally frustrating and enjoyable process to get to where I am, I've learnt a lot and have a much better understanding of electrics . However, the frustrating part has been the amount of conflicting information I keep coming across. The amount of posts, websites and videos I've read and watched, which all say different things has been painful. While I appreciate peoples opinions and individual views, which can be extremely helpful sometimes, certain aspects of projects like this needs facts rather than opinions.

I've even recently been told, by an actual auto electrician, that it will be fine to use 35mm2 cable with a 100A fuse for my 2000w inverter that will be connected with a ±5 meter cable and that voltage drop doesn't really occur over a 5m DC run! I'm taking that as complete garbage and ignoring all his advice.

I've ended up putting my plan together as best I can with a mixture of what I've learnt, valuable advice from members on this forum and in conjunction with doing the maths on the cables sizing and power ratings.

As I go through the installation, I will update this thread so it's accurate with exactly what I end up doing. I've ordered 95% of the kit already and started some of the install so will post that and more progress updates as I get in to it.

A full wiring diagram posted down below.

 

[8balladdict]

Current setup:​

• 110Ah Xtreme AGM battery (deceased)
• 15A Victron MPPT - No isolator
• CTEK D250SA B2B charger
• Victron BMV-712 Smart Shunt
• No emergency cutoff/isolator switch
• 3 random unlabelled fuse boxes
• Rainbow Dream 1 Amp

New setup: (Updated)​

• 230Ah Fogstar Drift seatbase lithium battery
• Emergency isolator switch
• 15A Victron MPPT - with isolator switch
• Victron XS 50A B2B charger
• Ablemail AMT12-2 trickle charger
• 12 blade fuse holder
• Victron Smart Shunt
• 300A negative busbar
• Maga/Midi fused positive distribution box
• 300A MRBF terminal fuse
• TransportHQ tailgate hidden rear panel hinge kit
• DEFA MiniPlug mains hookup connection point
• Twin double pole MCB/RCB
• Victron MultiPlus 12/1600/70 inverter/charger
• Victron VE.Bus Smart Dongle

 

[8balladdict]

Plan for installation and hardware location: (Updated)​

Most of this is going to be installed under the drivers seat where the existing kit is currently. I'll need to relocate the Dream 1 amp to the passenger seat which is currently filled with an JL Audio Subwoofer. It looks like this will fit in the gap at the front of the seat base though so I will just need to re-route the cables.

The DEFA MiniPlug hook-up connection point has been installed behind the hidden panel under the rear drivers side taillight, after the installation of the TransporterHQ hinge kit. I wanted the hookup point at the rear of the van for a couple of specific reasons so I went with this option.

The consumer units and the Victron inverter/charger are going to be installed in the garage at the rear of the van. The existing van furniture layout and configuration is dictating that this is the only viable location that I can install the inverter, and this has been a contentious subject in some of my other posts where I have been trying to plan this install but this is the only location it can realistically go.

Electrics Upgrade - Am I nearly there?​

I've messed up - Inverter Install​

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The single dual pole consumer unit will be used for the incoming AC supply from the DEFA MiniPlug. That will be hardwired to the MultiPlus. Then the outgoing AC supply from the MultiPlus will hardwired to a twin Dual pole RCD/MCB consumer unit before going to the 230v sockets. Only the MultiPlus will be grounded to the D pillar ground point.

For the MultiPlus install, I'm going to be following the principles in this YouTube video:

MultiPlus Install | Plans and Prep​

 

[8balladdict]

Cable Length, Sizing and Fuses: (Updated)​

This has been the most taxing part but I've done the maths and I think I'm pretty much there with most of it. I have made a couple of assumptions, which I'm not happy with doing, but I will document them later in this thread and hopefully get some clarification on them specifically.

The first run I needed to work out was the existing B2B charger cables, I was hoping it would be sufficient and then I wouldn't need to run a new cable through the dash threshold but no, it was only 6mm2. So this will be replaced with 16mm2 with 60A Midi fuses.

I'm going to use 16mm2 for the run from a 60A Midi fuse in the positive distribution box to the blade fuse holder and for the 1 meter run from a 40A Midi fuse to the passenger seat base to power the amp. Then going to use 6mm2 cable from the MTTP to a 20A Midi fuse. 2mm2 for the AMT12-2 trickle charger with 5A inline glass fuses. The mains 230v stuff is all going to use the 2.5mm blue arctic cabling.

Now for the inverter cabling. I’m either going to use 50mm2 or 70mm2 cabling for the run to the inverter. Victron recommends using 50mm2 for a run from 1.5m up to 5m. This cable will connected to the 175A mega fuse on the positive distribution box so well under the rating of the cable and less than the 200A internal fuse of the MultiPlus.

 

[8balladdict]

Grounding and Earthing: (Updated)​

I've ground out the factory chassis ground lug thats under the drivers seat so I can get the battery to fit nice and flat so the 300A negative busbar will be connected to one of the seatbase securing bolts. I've seen a thread about making sure thats a sound ground point so I'll follow that as part of this process.

Seatbase GND Connection​

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So the negative terminal of the leisure battery will be connected to the Smart Shunt and then to the negative busbar. The rest of the equipment being installed under the seat will all be connected to the negative busbar.

The negative cable from the MultiPlus will run back to the negative busbar under the seat and I'm not going to earth either of the consumer units to the chassis, only the ground point of the MultiPlus will be connected to the D pillar ground point. This seems to be the recommended installation method by Victron and more information was detailed in the following YouTube video:

MultiPlus Install | Plan and Prep​

 

[TallPaul_S]

Have you already got the solar panel? If not, is there an option of going any bigger?

I ask, because induction cooking on the inverter absolutely rinses the battery! For example, on my 230Ah Fogstar battery, 20 minutes at full power on a single 800w induction hob, drains 10% of the battery - 23Ah. If you're off grid and relying on solar, you can very very quickly find yourself using far, far more than your solar is putting back in.

Cooking on an evening for 30 mins - 30-40Ah
Boiling the kettle in the morning - 10Ah

Then add on your fridge usage (25Ah per day), charging, lights etc. And all of a sudden you're at 80+Ah usage per day.

The most I've ever had from my 305w panel and 20a MPPT is 800Wh, or 66Ah. On a cloudy day, that's more like 400Wh, or 30-odd Ah.

A 130w solar panel is unlikely to keep up with any proper induction cooking if you're off grid with no hookup. If you're not going to be, then it's not really an issue!

 

[8balladdict]

Yeah, the panel is already installed. Will probably look to upgrade or add to it going forward as I know it's not going to up to the job. Will just need to be selective as to when I use the inverter until then I guess.

 

[TallPaul_S]

Yeah, the panel is already installed. Will probably look to upgrade or add to it going forward as I know it's not going to up to the job. Will just need to be selective as to when I use the inverter until then I guess.

I've got gas as a backup so worth thinking about this - induction is much much easier but if I parked up for a few days in a shady spot or with crap weather I can always resort to using gas. Just with fridge usage and no induction stuff my battery got down to 50% over a few days with very little solar.

 

[8balladdict]

I've got gas as a backup so worth thinking about this - induction is much much easier but if I parked up for a few days in a shady spot or with crap weather I can always resort to using gas. Just with fridge usage and no induction stuff my battery got down to 50% over a few days with very little solar.

I've got two different Cadac's and one of those stoves that takes the aerosol type gas canisters, which has been my mainly used one to date to be fair so yeah, I can still make use of them when required.

 

[EAN]

I wouldn’t use the Renogy Inverter for the type of installation you are planning.
It’s only designed to be used standalone as it has a floating earth.
I have a 1000W version and keep it seperate from the EHU sockets.
I also made a conscious decision not to connect the chassis earth of the Renogy to the van chassis as the van chassis isn’t connected to a proper earth unless on EHU, so in certain fault conditions it’s not good to do so.

Seriously consider switching to a Victron which is designed to handle the neutral/earth link correctly.
When on EHU the neutral/earth link comes from the EHU supply and it’s a NO NO to having a neutral/earth link elsewhere.
When not on EHU you want the inverter to give you a neutral/earth link.
But, the issue is where is the earth actually coming from as the van is isolated from earth unless you are adding a GND stake externally? Which you probably aren’t.

Have a read of this, if you haven’t already.

7. Ground, earth and electrical safety

www.victronenergy.com

 

[8balladdict]

I wouldn’t use the Renogy Inverter for the type of installation you are planning.
It’s only designed to be used standalone as it has a floating earth.
I have a 1000W version and keep it seperate from the EHU sockets.
I also made a conscious decision not to connect the chassis earth of the Renogy to the van chassis as the van chassis isn’t connected to a proper earth unless on EHU, so in certain fault conditions it’s not good to do so.

Seriously consider switching to a Victron which is designed to handle the neutral/earth link correctly.
When on EHU the neutral/earth link comes from the EHU supply and it’s a NO NO to having a neutral/earth link elsewhere.
When not on EHU you want the inverter to give you a neutral/earth link.
But, the issue is where is the earth actually coming from as the van is isolated from earth unless you are adding a GND stake externally? Which you probably aren’t.

Have a read of this, if you haven’t already.

7. Ground, earth and electrical safety

www.victronenergy.com

Thanks for the info @EAN. If I had the choice I’d definitely be going with the MultiPlus but unfortunately there definitely isn’t room to install one of them in this van. I will have another look at the Victron inverters though. Not completely happy with the lack of technical detail in the Renogy inverter manual.

 

[t0mb0]

Given 120mm2 cable is about 2cm in diameter, i.e. absolutely huge, have you thought about the physical aspects of routing and terminating it? The bend radius alone will make it extremely difficult to get around anything approaching a corner I would have thought?

 

[8balladdict]

Given 120mm2 cable is about 2cm in diameter, i.e. absolutely huge, have you thought about the physical aspects of routing and terminating it? The bend radius alone will make it extremely difficult to get around anything approaching a corner I would have thought?

Of course I have, yeah. Pretty much keeping it floor level, planning on drilling a hole in the bottom of the seatbase somewhere near the back and then with a gland and some conduit or a grommet, running it out and down in to the step void under the floor (I have a twin slider) and then back up into the rear cupboards. I think it’s still kind of flexible and I should be able to avoid any 90° bends or anything excessive. It’s also the reason why I’m planning on sticking with 50mm2 cabling for the main short battery connections under the seat as it’s going to be impossible to use the ‘absolutely huge’ cabling for those bits.

 

[TallPaul_S]

Of course I have, yeah. Pretty much keeping it floor level, planning on drilling a hole in the bottom of the seatbase somewhere near the back and then with a gland and some conduit or a grommet, running it out and down in to the step void under the floor (I have a twin slider) and then back up into the rear cupboards. I think it’s still kind of flexible and I should be able to avoid any 90° bends or anything excessive. It’s also the reason why I’m planning on sticking with 50mm2 cabling for the main short battery connections under the seat as it’s going to be impossible to use the ‘absolutely huge’ cabling for those bits.

50mm² is just about manageable within the seat base with a 230Ah battery in there. It's what I've used for all my main runs to the shunt, main distribution box, and the inverter wiring.

 

[8balladdict]

50mm² is just about manageable within the seat base with a 230Ah battery in there. It's what I've used for all my main runs to the shunt, main distribution box, and the inverter wiring.

View attachment 261940

Yeah, I’m going to try and be clever with where I put the components to make the cabling runs as easy as possible.

 

[8balladdict]

** UPDATE **

Thanks to @EAN for the advice on the Renogy. I was not convinced with it in all honesty so I've had another look at the options and I think I'm now going to go for a MultiPlus 12/1600/70. By doing this it means I can downsize the cabling to either 50mm2 or 70mm2, I don't need to install the IP22 which reduces more cabling running from the back of the van to the battery but also removes the need to ground to the D pillar.

It does mean I'm downsizing on the output of the inverter but I can deal with that. I'll also need to get another consumer unit but thats fine. I'm much more conformable with this install and at least I know the MultiPlus handles the neutral earth bonding stuff automatically. Plus it has a higher charge rate that the IP22 and by removing the IP22, I can now route my solar back through the mega/midi fused distribution box rather than the blade fuse holder. I'm not going to use the second battery charger function as I'm going to stay with the AMT12-2.

New diagram below:

 

[EAN]

@8balladdict glad my link helped: Your update looks much better.
On the solar isolator remember to use a DC double pole to disconnect both cables. I like the look of these and am going to use one on my solar install:

Cudis CPN GR232/DC 32A, 2 Pole IP66 Enclosed DC Rotary Isolator

In Stock for Fast FREE Delivery (£150+) - Buy the Cudis CPN GR232/DC for just £36.94 and view our range of 2 Pole Isolators online today!

www.electricalcounter.co.uk

 

[8balladdict]

@8balladdict glad my link helped: Your update looks much better.
On the solar isolator remember to use a DC double pole to disconnect both cables. I like the look of these and am going to use one on my solar install:

Cudis CPN GR232/DC 32A, 2 Pole IP66 Enclosed DC Rotary Isolator

In Stock for Fast FREE Delivery (£150+) - Buy the Cudis CPN GR232/DC for just £36.94 and view our range of 2 Pole Isolators online today!

www.electricalcounter.co.uk

Can I not just use the switch? I don't have room under the seat for double pole isolator so that's why I'm going for the switch. If I need to do work on the system, I'm happy to disconnect the incoming cables to the MPPT if needs be.

 

[EAN]

Can I not just use the switch? I don't have room under the seat for double pole isolator so that's why I'm going for the switch. If I need to do work on the system, I'm happy to disconnect the incoming cables to the MPPT if needs be.

If you are going to add an isolater to the solar panel then, yes, it's both cables: You can isolate where the solar enters rather than near the MPPT if that makes it easier.
I would definitely install one.

Edit: Been reading up on this a bit more. Apparently, on a Victron MPPT there is no isolation between the input and the output. That means that once wired in the negative of the solar array would be gnded through to the battery negative via the MPPT. If this is actually the case then I see no reason why you can't just isolate the positive of the PV array and use a single pole isolator, despite my previous statement to the contrary.
You might not be truly isolating the array in totality but it's as good as.
Need someone to confirm if there is a link between the solar PV negative and the battery negative terminals on a Victron MPPT.

 

[8balladdict]

If you are going to add an isolater to the solar panel then, yes, it's both cables: You can isolate where the solar enters rather than near the MPPT if that makes it easier.
I would definitely install one.

Edit: Been reading up on this a bit more. Apparently, on a Victron MPPT there is no isolation between the input and the output. That means that once wired in the negative of the solar array would be gnded through to the battery negative via the MPPT. If this is actually the case then I see no reason why you can't just isolate the positive of the PV array and use a single pole isolator, despite my previous statement to the contrary.
You might not be truly isolating the array in totality but it's as good as.
Need someone to confirm if there is a link between the solar PV negative and the battery negative terminals on a Victron MPPT.

I did try clarifying this with 12vPlanet and initially they said you do need a double pole but when I mentioned the the line in the Victron manual they seem to agree that a single pole switch will be fine