EHU charger/inverter

frizzuti

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I’ve got a Victron multiplus 12/1200/50 and struggling with where to install it. I’ve got very limited choice due to my set-up. I read that it’s best to posn the inverter as close as possible to the leisure battery - is this simply to reduce the power cable lengths and therefore reduce the thickness as voltage drop is less the shorter the cable?

The Victron tech manual suggests a distance of 1.5 - 5m needing a 35mm2 cable. Am I right in saying that the +ve cable obviously connects between the battery and Victron but the -ve can go to chassis ground closer to the Victron?

As you can see from the photo this dead space at the D Pillar is the only place really workable as I have to accommodate the height of the sliding seat. My plan is to build a metal plate or wooden box enclosure with a openable lid so I can get to the switch and terminals. The manual also says the unit needs 10cm free air gap to aid cooling. I won’t really have that but is that going to be an issue?

Finally, I think I may have to go to the next size unit down, as it’s small dims and would fit easier in the same space. That would be the 12/800/35. This needs a 25mm2 cable.

For context I have a twin slider LWB with a full-width 150cm seat/bed that slides on full-length rails, so no side cabinets at all. The main components of my set-up are as follows:

- 230Ah leisure battery- seat base (dvr)
- Victron Orion XS 12/12 50A DC to DC charger
- no solar as I just want DC to DC and Mains EHU

The other problem is where to fit the mains consumer units x 2 - they’re pretty big too! I was thinking of making a hatch in the van side ply panel then secure them to a piece of wood. But again not sure they will fit?

The reason for two consumer units is because I want a set of 240v sockets (double mains + 12v DC) in the rear quarter panel and same again mounted to the back of the dvr seat base.

It’s also going to be tight fitting all the components in the seat base - similar to @Dellmassive - how I done it post.

Any help with above much appreciated!

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Yes the negative cable can go direct to the chassis a short as possible.

If you are looking to mount the unit that far back in the van I'd say you might need to step up on the positive feed cable size.

Iron managed to squeeze in the viktron 3 kVA inverter in the side cabinets under the sink. 75mm2 cable.

Are you planning to have any cabinetry or a bed or seats or anything in the van?

Why do you want to put the multiplus by the deep healer question mark is there a particular reason for that?.

Can you not find a space at the front of the van near the seat basis so it's close to the 12 volt DC battery?
 
Surely you can run all the mains sockets from one consumer unit as a radial circuit. Remember when you’re on hook up at a campsite if you run too many things at once you’ll trip the campsite anyway
 
Yes the negative cable can go direct to the chassis a short as possible.

If you are looking to mount the unit that far back in the van I'd say you might need to step up on the positive feed cable size.

Iron managed to squeeze in the viktron 3 kVA inverter in the side cabinets under the sink. 75mm2 cable.

Are you planning to have any cabinetry or a bed or seats or anything in the van?

Why do you want to put the multiplus by the deep healer question mark is there a particular reason for that?.

Can you not find a space at the front of the van near the seat basis so it's close to the 12 volt DC battery?
The reason I went for the multiplus 1200VA was it’ll only take just over 4hrs to charge my 230Ah battery, vs about 6hrs with the 800VA - I suppose any stop at a campsite would be over 6hrs so probably ok to go for the 800VA.

I don’t want any cabinets, whilst I want to hookup at a campsite I only really want to sleep in the van, no cooking. I’m only really wanting to power off mains things like, compressor fridge unit (portable), laptop, fans, maybe hair dryer.

Because the seat/bed if full-width and slides front to back there is nowhere to fit cabinets anyway. My use cases are mainly day-van for going to cycling events and wk ends away with the family plus longer trips to Europe.

There’s no space at the front of the van. I have a double passenger seat base that slides and swivels so it can’t accommodate anything electrical due to cabling becoming snagged. That’s why the only place it’ll fit and is out of the way is the rear D Pillar corner.
 
For the loads you have described, 50A charging capacity from the multiplus seems massive overkill.

What's going to discharge your leisure battery completely so that you need to fully charge it overnight?

For similar sorts of loads, I have the following
Consumer unit under the bonnet.
Victron. IP65 15A charger when on EHU. (Could also be under the bonnet)
Orion xs dc-dc
Fogstar 230Ah seatbase battery
Renogy 1kW inverter mounted on back of drivers seat.

Something like this would meet the needs you describe ( both solutions require a low power/travel hairdryer to be 1kW or under)

I also have 150W solar panel, but then I don't use EHU that much

Simon
 
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I know you haven't got cupboards but that's a Renogy 2kw inverter and by the side of it there's a Victron 30A charger, both of these could go horizontally on that board at low level on the back of the seatbase in yours?
Yes the Webasto heater outlet is in the way.
 
For the loads you have described, 50A charging capacity from the multiplus seems massive overkill.

What's going to discharge your leisure battery completely so that you need to fully charge it overnight?

For similar sorts of loads, I have the following
Consumer unit under the bonnet.
Victron. IP65 15A charger when on EHU. (Could also be under the bonnet)
Orion xs dc-dc
Fogstar 230Ah seatbase battery
Renogy 1kW inverter mounted on back of drivers seat.

Something like this would meet the needs you describe ( both solutions require a low power/travel hairdryer to be 1kW or under)

I also have 150W solar panel, but then I don't use EHU that much

Simon
Simon huge thanks for this, it’s adding real value to my design. So with your IP65 have you wired that directly into the EHU connection, as they come with a mains plug attachment?

And then you use your Renogy as the inverter attached to seat base. Do all renogys have a mains plug socket on the side of the unit? As this could negate me needing a separate mains socket which was going on the seat base board (but now could be the inverter).

Did you choose a separate charger and inverter purely to avoid a singular large box needing a place to fit?

Also, do you have a pic of the consumer unit and IP65 in situ under bonnet pls?
 
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I know you haven't got cupboards but that's a Renogy 2kw inverter and by the side of it there's a Victron 30A charger, both of these could go horizontally on that board at low level on the back of the seatbase in yours?
Yes the Webasto heater outlet is in the way.
Thanks for this. What’s your Victron 30A charger, IP22? Not sure both that and the renogy would fit side by side on the back base board?

Also, with your charger, how have you wired this into your EHU point? They come with mains plugs - did you cut this off and wire into the consumer unit?
 
The 2kw Renogy inverter is physically quite a lot bigger than the previous 1kw version we had but with a 230Ah battery it seemed a shame to not cater for the occasional extra 230Vac capacity ie kettle and toaster
The Victron is the IP22 12/30 unit and plugs into an adjacent conventional domestic 13A single skt wired, as you guessed, to the EHU fuse board.:thumbsup:
 
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