Victron Multi and 600ah battery bank

[Carpe Diem]

Good evening all, I'd like to say hello and pick your collective brains please!

I've got a 2007 LWB Sprinter that I'm trying to tweak into a mobile man cave. (Armchair, simple cooking stuff, and massive TV)

I am more mechanically minded than electrically, but I've managed to cobble together a system in my van.

I've got a few things, but can't work out my charging of batteries 90% of the kit was installed in the van when I bought it, and I've just moved some of it and added a bigger bank of batteries, and purchased a solar controller

The equipment I have:-

Victron Multiplus 12/3000/120
Victron Smart solar MPPT 100/20 (wrong I think)
CTEK C250SA
4x Haze HZB12-150FA batteries in parallel.

Why can't I charge them properly? (I'm sort of thinking I need a smartpass or something else) I've read a lot of @wildebus things, but I'm seemingly not bright enough to get my head round it.

Is anyone good with simple crayon drawing suggestions that I can follow?

Thanks in advance all, and keep up the cool builds

 

[Nabsim]

Wait for someone else but what source are you using to try and charge your battery bank? Engine via the CTek, solar via the MPPT, mains via the MultiPlus? Again wait for someone else but I don’t think you need the MPPT with having the Multiplus but I can frequently be wrong
How many watts of solar do you have fitted, that will also help others answer

 

[Carpe Diem]

Wait for someone else but what source are you using to try and charge your battery bank? Engine via the CTek, solar via the MPPT, mains via the MultiPlus? Again wait for someone else but I don’t think you need the MPPT with having the Multiplus but I can frequently be wrong
How many watts of solar do you have fitted, that will also help others answer

Hey Nabsim, thanks for the reply!
I'm currently using the engine and mains thru the Multiplus at home.
I'm not sure about how many watts of solar I'd need. My head tells me that I'll need 600w of solar to charge the 300ah (50%) of the battery bank I have.

I'm not sure if I need a cerbo with display, or a bmv712. I have so many questions haha. I've just downloaded the Multiplus manual, so I'm going to have a good read of it.

Again, thanks for the insight

 

[wildebus]

600Ah is a big battery bank of course and can take some recharging!

Your system with 600Ah of HZB12-150FA Batteries sounds very similar to my last van which also had a 12/3000/120 Multiplus and 645Ah of Northstar Blue+ Telecom batteries.

Let assume you take it down to half-way (300Ah used) and need to recharge ....

HOOKUP
Your Multiplus has a 120A (max) AC-DC Charger. By default, that will be set to 95A and you need to reprogramme to get the full 120A output. As they are Lead-Acid batteries, the charge rate slows down as the batteries fill up. If you are camped up somewhere where you have EHU overnight, you will have fully recharged batteries by the time you are ready to be on your way.

DRIVING
Your CTEK 250SA is a decent DC-DC Charger, but is only 20A. Flat out it will take a fair drive to make in-roads on a 50% discharged bank. For your sized battery bank, I think the Smartpass to take you up to a theoretical 120A charge rate could be worth doing. How close you get to the 120A will depend on the alternator and the level of battery discharge, but you will certainly improve significantly on the 20A I am sure.

OFF-GRID
You say Victon 100/20 but say you "wrong, I think". Wrong choice you are thinking? or it is a different size/model?
a 100/20 Controller will support upto 290W of PV Panels, which is not a great deal to match up to a 600Ah battery bank, especially in the UK and very especially in the UK outside of summer. Assuming you bought the controller to match the array size, if you can add more panels (a LWB Sprinter has room for over 600W of PV on the roof (dependant on roof vents, etc.) that would be a definate advantage.



I was off grid for around a week last month and my current 500Ah bank went down to around 100Ah remaining. I found my solar (270W into a Victron 100/20) was handy for providing a boost but did not give me a battery with more charge at the end of the day than I started with. My solar is not large enough either, but I don't have room for more and I don't ration my battery use, so what I saw is what I expected. My solution was to go to a campsite with EHU when I left the Off-grid site and let the Mains Charger fully replenish the battery ready for the next few days of off-grid camping
If I were doing a long day drive to the next site (like the 400 mile trip about a week later), then I would have relied on the 60A B2B to do the bulk of the recharging.

The best charging options really does depend on how you tend to use your campervan. Your Mains Charger is good enough for sure. Your Solar and B2B is certainly limited for your Battery Bank size.

 

[wildebus]

Wait for someone else but what source are you using to try and charge your battery bank? Engine via the CTek, solar via the MPPT, mains via the MultiPlus? Again wait for someone else but I don’t think you need the MPPT with having the Multiplus but I can frequently be wrong
How many watts of solar do you have fitted, that will also help others answer

The Multiplus is a AC-DC Charger and DC-AC Inverter. No Solar Capability within it unless you get the "EasySolar" version - but that is quite literally a Multiplus in a bigger casing with a standard SmartSolar MPPT housed inside it and pre-cabled up.

 

[Carpe Diem]

600Ah is a big battery bank of course and can take some recharging!

Your system with 600Ah of HZB12-150FA Batteries sounds very similar to my last van which also had a 12/3000/120 Multiplus and 645Ah of Northstar Blue+ Telecom batteries.

Let assume you take it down to half-way (300Ah used) and need to recharge ....

HOOKUP
Your Multiplus has a 120A (max) AC-DC Charger. By default, that will be set to 95A and you need to reprogramme to get the full 120A output. As they are Lead-Acid batteries, the charge rate slows down as the batteries fill up. If you are camped up somewhere where you have EHU overnight, you will have fully recharged batteries by the time you are ready to be on your way.

DRIVING
Your CTEK 250SA is a decent DC-DC Charger, but is only 20A. Flat out it will take a fair drive to make in-roads on a 50% discharged bank. For your sized battery bank, I think the Smartpass to take you up to a theoretical 120A charge rate could be worth doing. How close you get to the 120A will depend on the alternator and the level of battery discharge, but you will certainly improve significantly on the 20A I am sure.

OFF-GRID
You say Victon 100/20 but say you "wrong, I think". Wrong choice you are thinking? or it is a different size/model?
a 100/20 Controller will support upto 290W of PV Panels, which is not a great deal to match up to a 600Ah battery bank, especially in the UK and very especially in the UK outside of summer. Assuming you bought the controller to match the array size, if you can add more panels (a LWB Sprinter has room for over 600W of PV on the roof (dependant on roof vents, etc.) that would be a definate advantage.



I was off grid for around a week last month and my current 500Ah bank went down to around 100Ah remaining. I found my solar (270W into a Victron 100/20) was handy for providing a boost but did not give me a battery with more charge at the end of the day than I started with. My solar is not large enough either, but I don't have room for more and I don't ration my battery use, so what I saw is what I expected. My solution was to go to a campsite with EHU when I left the Off-grid site and let the Mains Charger fully replenish the battery ready for the next few days of off-grid camping
If I were doing a long day drive to the next site (like the 400 mile trip about a week later), then I would have relied on the 60A B2B to do the bulk of the recharging.

The best charging options really does depend on how you tend to use your camper van. Your Mains Charger is good enough for sure. Your Solar and B2B is certainly limited for your Battery Bank size.

Wildebus, Thank you for the in depth there. Exactly the info I needed in simple terms for a simpleton like me. Appreciate it.

By wrong for the MPPT, I mean wrong as in I was told to buy the wrong one by a company, and the wrong amount of watts of solar. I've found a single 550w panel for sale, which is 2.1m x 1.4m. I was hoping this might be enough to cover my needs. I don't intend to be off grid too much. A couple of days or so here and there, both winter and summer, and I don't mind driving a couple of hundred miles at a time, so I'd agree with you about the Smartpass. I read your post about your version, and it made sense. I can use an S class Mercedes high output (200amp) alternator to boost the output to it.

I don't have any proper battery monitor stuff, so I'm thinking a Cerbo Gx with a screen would be awesome. or a Pi with Venus. I might be getting ahead of myself. I know this would be useful to program the multi at least.

from all that I've read and sort of understood, I think a 100/50 MPPT would be more like what I need if I'm running one single large panel?I don't really want to ration my battery use either, as the primary idea is to get away by myself, explore some scenery, come back and have a BBQ/sit by the fire and stargaze, perhaps watch a movie on the big screen in the middle of nowhere, so as not to disturb others.

I intend to buy one of those 93L fridges you tested, and they are back in stock at amazon. So I'm thinking I should buy another inverter also and set it up as you did in your blog post? Lots of other questions, so I'd like to know If I can book, and pay for a consultation from you thru your site. I did try and give you a call, (07*** **0004) but I don't want to pester, and I know your time is valuable. Much like your knowledge!

Thanks for all the info so far!

 

[MarkJ]

That is some TV....awesome....

 

[Carpe Diem]

That is some TV....awesome....

Thanks Mark, it all started from not being able to go to the cinema in Lockdown....

 

[SquirrellCook]

Unless the victron info is wrong, I think you need a windows PC to program the Multi's
With the Cerbo, David would have a very big grin viewing it on your tv.

 

[SquirrellCook]

wrong post

 

[wildebus]

Wildebus, Thank you for the in depth there. Exactly the info I needed in simple terms for a simpleton like me. Appreciate it.

By wrong for the MPPT, I mean wrong as in I was told to buy the wrong one by a company, and the wrong amount of watts of solar. I've found a single 550w panel for sale, which is 2.1m x 1.4m. I was hoping this might be enough to cover my needs. I don't intend to be off grid too much. A couple of days or so here and there, both winter and summer, and I don't mind driving a couple of hundred miles at a time, so I'd agree with you about the Smartpass. I read your post about your version, and it made sense. I can use an S class Mercedes high output (200amp) alternator to boost the output to it.

I don't have any proper battery monitor stuff, so I'm thinking a Cerbo Gx with a screen would be awesome. or a Pi with Venus. I might be getting ahead of myself. I know this would be useful to program the multi at least.

from all that I've read and sort of understood, I think a 100/50 MPPT would be more like what I need if I'm running one single large panel?I don't really want to ration my battery use either, as the primary idea is to get away by myself, explore some scenery, come back and have a BBQ/sit by the fire and stargaze, perhaps watch a movie on the big screen in the middle of nowhere, so as not to disturb others.

I intend to buy one of those 93L fridges you tested, and they are back in stock at amazon. So I'm thinking I should buy another inverter also and set it up as you did in your blog post? Lots of other questions, so I'd like to know If I can book, and pay for a consultation from you thru your site. I did try and give you a call, (07*** **0004) but I don't want to pester, and I know your time is valuable. Much like your knowledge!

Thanks for all the info so far!

Certainly drop me a note and we can talk I think some extra monitoring of the system is both useful and also fun

Ref the 93L Fridge ... I have one for sale if you are interested and in a location you can collect. Bought as a backup to the campervan one but never needed it as the original just kept working 24/7 without missing a beat. Was plugged into new van for around a week between taking out old 3-way and fitting big fridge-freezer so essentially still pretty well brand-new.

After I changed to the Multiplus 12/3000, I ran the Fridge off the same inverter as the rest of the AC devices - and after setting it up in the energy-saving mode so it is only on when needed I found that is a good way to go. A separate small inverter WILL be more power-efficient I would expect, but a good one you would be happy to leave unattended, and to be powered 24/7 and be silent would not be that cheap.

What you could do with the 100/20 controller is keep it and use it for a couple of external panels - so if you decide to got away for a few extra days into the wild, you could get some useful extra harvesting on top of what the big roof panel gives on via a 100/50? (I fitted a pair of 100/20s on the new motorhome - one for the 270W on the roof and the second for a portable kit to take me when appropriate).

 

[wildebus]

Unless the victron info is wrong, I think you need a windows PC to program the Multi's
With the Cerbo, David would have a very big grin viewing it on your tv.

It would be good
The Cerbo's HDMI output is designed to be used with a 5" or 7" screen, but when I connected a 32" screen to it, I was honestly amazed at how good the image was! Expected it to be blocky and a bit horrible blown up to that size but it was great

Ref Programming, you do need a Windows PC to program the Multiplus via VE..Config, you are correct.
What the Cerbo (and other Venus OS devices) gives you however is the ability to send saved config files to the Multiplus. Without a Venus OS device you need to connect the Windows PC up to the Multiplus via the Victron VE.Bus - Mk3 Dongle cable, so having the Cerbo or the like does make it much easier. And as you are just sending a file, that could maybe be a file saved on a tablet or phone even? (I have not tried that, but it should work?)
And if you get really funky, you could have a bank of Config Files programmed for different types of operation (maybe one for when in Storage, one for Camping and one for "Cinema Mode"? how they would vary I wouldn't know off the top of my head but the possibility is there )