1400w solar, Mpp Solar 24v 3kw, 150ah DIY Lipofe4 RV set up

Hi guys,
I'm building a campervan here in UK which is rather different the the most RV over here and that is why I'm having problems finding information regarding set up.
In UK most set ups is LPG feed with no or small PV installations probably because of the weather here is not great?
I'd like to go with you through this system I'm planning to build and I'd let you know what I've already bought for it. If you'd see any issues with it I'll be very grateful for any advice as I'm fairly new to this topic.
I want my van to be fuelled only be diesel and solar, no LPG.
I've already bought 4x350w LG NeOn2 which I want to connect in series with 24v3kw mpp solar (max vdc 500v). I've bouth 6mm SOLAR XLS cable to connect those panels with mpp solar.
I've bought on aliexpress set of 8 150ah 3.2v lifepo4 cells and Smart Bluetooth 7S-20S CELL Lifepo4 li-ion 320a bms which now waiting for. The battery will be 1m away from Inverter/Charger so I'm not sure about the wire gauge, 1awg?
I also want to use smart DCtoDC 12/24v 15a charger by Victron which I've been told to connect this straight from battery to the battery!?
I know that I'll need some fused circuit breakers for this set up. Which ones would you recommend?
I was thinking about 30a on the positive PV array, 200a on positive battery to inverter/charger and 20a for dc to dc charger when installed.
If I've missed something else please let me know. I'd appreciate any advice even the most critical ?
Thank you

Hi,

You're not the only one, I'm looking into a quite similar build here in Ireland.
I've been looking into the same MPP solar inverter and similar sized solar setup on a low loader / low profile luton van.
If you say max vdc 500v i suppose you mean the PIP3024GK one (http://www.mppsolar.com/v3/catalogs/PIP-GK.pdf).
The problem I was facing (especially with this kind of solar setup is the MPPT range of 120 - 450VDC.
Take the Vmpp of your panels at 35.30V in series you'll get 141.2V.

My understanding here (please anyone correct me). That's at max power which won't be the case for most of the time in the UK. Looking at the voltage chart of any panel the voltage drops significantly at lower production rates. Once you drop below 120V your MPPT controller stops charging. That's why I was considering a 3S configuration with panels that just about maxing out the 145VDC of the "normal" MPP Solar controllers to have enough room down. Or, get higher voltage panels such as the Panasonic HIT N 335W with about twice the Voltage but half the amps to use on the 500V controller.

I'm still in the middle of my research but that's where I am so far and I wanted to share it since it's a similar setup in a similar climate.

the_tux said:

Hi,

You're not the only one, I'm looking into a quite similar build here in Ireland.
I've been looking into the same MPP solar inverter and similar sized solar setup on a low loader / low profile luton van.
If you say max vdc 500v i suppose you mean the PIP3024GK one (http://www.mppsolar.com/v3/catalogs/PIP-GK.pdf).
The problem I was facing (especially with this kind of solar setup is the MPPT range of 120 - 450VDC.
Take the Vmpp of your panels at 35.30V in series you'll get 141.2V.

My understanding here (please anyone correct me). That's at max power which won't be the case for most of the time in the UK. Looking at the voltage chart of any panel the voltage drops significantly at lower production rates. Once you drop below 120V your MPPT controller stops charging. That's why I was considering a 3S configuration with panels that just about maxing out the 145VDC of the "normal" MPP Solar controllers to have enough room down. Or, get higher voltage panels such as the Panasonic HIT N 335W with about twice the Voltage but half the amps to use on the 500V controller.

I'm still in the middle of my research but that's where I am so far and I wanted to share it since it's a similar setup in a similar climate.

Click to expand...

Thank you so much for pointing this out to me.
I have already started the return procedure for my PIP3024GK to swap it for the PIP3024 MSXE with the voltage range 30-115v.
I must admit that this is the one I was referred to by the manufacturer for my set up but somehow overlooked it and I've ended up with similar but different model?‍
I'm very grateful that you have spotted this.
So with this new voltage range I'd just set my panels in two strings of two panels so I'd end up with max 68v which is well within the charge controller range (please someone correct me if I'm wrong).

Ps
I've always liked the idea of a low loader luton for conversion. Great living space and straight walls everywhere...ideal scenario. The only issue for me with their layout was back entry door (shutter). I needed garage space for my ebikes that's why I've bought Citroën Relay L4H2 so I can build it under the bed. Also the price and mileages for lowloader luton was both extremely high.
I hope that everything will go smooth with your project?