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drivebywire avatar image
drivebywire asked

VE-Bus BMS, CCGX, VE.Direct MPPT Charger - Battery Protection through VE.Direct Connection?

Hi all,

I´m currently planning on my system for the new RV coming in May.

I plan to use two 160AH Victron Lithium with the VE.Bus BMS and a CCGX connected to a 12/3000 Multi. So far everything clear.

But how does the MPPT 100/50 come into the equation? In the VE.Bus BMS manual there is a VE.Direct non inverting direct remote cable mentioned for connecting to the BMS. When I use that, of course I don't get readouts on solar in the CCGX and can't configure my device this way and with the Victron Portal.

If I connect the VE.Direct from the MPPT to the CCGX, is the "stop charge" or "reduce charge current" signal transmitted via VE.Direct to the MPPT? Like it is to the Multi through its VE.Bus? I´m unsure because there are system diagrams with the big MPPT 150-85 VE.Can solar chargers in my desired configuration, and even these have the yellow cable for "stop charging" or "shutoff" hard wired, despite being connected via VE.Can...

I don´t get secure documentation on this - perhaps you could enlighten me ;)

All the best, Martin.

MPPT ControllersLithium BatteryBMSCCGX Color ControlVE.Direct
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4 Answers
Paul B avatar image
Paul B answered ·

All I can sugest is give it a go and then let us all know the results. here on the forum,

someone has to do the testing and configuration, and we then pass that onto others when we can.

I suspect that it does all you are asking but I have not had a system that I have installed that has that requirement so I cant give you a cut and dried answer.

at the Moment as this has not been answered no one knows the full answer


Sorry

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boekel avatar image
boekel answered ·

When you connect a bms to the Venus GX / Color Control GX, set it to be the 'battery monitor' and any connected MPPT's will go into 'networked' mode and listen to the BMS.

You don't need other connections, things will probably even work without changing settings (but please check them)

The CANbus connected MPPT's can have some issues with CANbus connected batteries, in those cases they have to be wired differently,

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drivebywire avatar image
drivebywire answered ·

Thank you both (@Boekel, @Paul B) for your answers! I thought I wouldn´t get any answer at all ;-)

As it seems, all chargers except the Multis / Quadros have to be cut off using a Battery Protect; VE-direct does not the job. So, I ordered a BP220 for all 12V systems, and two BP65 for B2B-Charger and MPPT. These are switched off in case of over voltage through the BMS.

When it is installed and ready, I will post my results...


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boekel avatar image boekel ♦ commented ·

I think you're over complicating things.

Can you make a diagram how you intent to wire things?

the MPPT can be controlled by the Venus / CCGX, B2B charger likely has an 'enable' input you can control by the bms 'charge enable' output. And you might want to use the generator relay from the Color Control to switch this B2B charger on / off (linked through the charge enable line)

using a bp for 12V users is a good plan, but do you have such big users you need a 220A version?

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drivebywire avatar image drivebywire boekel ♦ commented ·

you write "the MPPT can be controlled by the Venus / CCGX" - as of everything I read on the net, that does not seem to be the case, at least not always...

My initial question sparked from this drawing here (copyright Victron):

Obviously, the VE.Direct port is blocked because of the connection to the CCGX.

"Some people have chosen to rely on the Victron MPPT solar controller being connected to the Color Control GX via a Victron control bus, but it was highly recommended to have this Battery Protect, as there are some situations where the CCGX will not command it off." (can be found here).

Similar suggestion from another user (who sells Victron Equipment and says "The Color Control cannot control the MPPT, I dont know why, it just can't." (can be found here). There is a schematic of this dealer (I post it here, copyright PKYS):

They are using BPs to cut off the MPPT as well... last Revision is December 2018, so I thought this is still not outdated?

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boekel avatar image boekel ♦ drivebywire commented ·

Well I'd like to know in what situations the Color Control cannot controll the MPPT.
What I don't like about the diagram by PKYS is the amount of stuff connected in front of the disconnect switch, you can empty the battery on the current draw of the BMS, multi controll and BMV.

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drivebywire avatar image drivebywire boekel ♦ commented ·

I´ve already asked him in his blog post ;-)

I agree with you with the permanent connections. The BMS and the BMV have minimal draw - the VE-Bus BMS has 2mA draw on cell low power disconnect, and the BMV draws <4mA. Means, that even a 320Ah Lithium would be completely dead and defect after 20 days when there is a low power disconnect and no one is there for charging... I prefer to disconnect the complete system when I´m not using it.

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big-ste avatar image big-ste drivebywire commented ·

what about using the BMV 712 with a relay to disconnect the battery?

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drivebywire avatar image drivebywire big-ste commented ·

What would the benefit be? In this case I would rather the BMS command the shut off on cell basis, not the BMV on overall SOC Basis... and I would need the BP anyway.

I would like to get rid of the BP and control the MPPT through VE.Direct Bus directly from the CCGX. That´s the question.

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drivebywire avatar image drivebywire boekel ♦ commented ·

BTW (second post, because of 1000 char limit):

I need the BP220 for cut-off of 12V because of the Caravan Mover System - four electric motors, drawing max. 150Amps if you have demanding situations.

If it would work without the BPs for charge cut-off, this would be even better and very straightforward. I would like that even more, but because of these two very detailed posts above I was unsure of how to wire my solution.

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big-ste avatar image
big-ste answered ·

Hi Martin,

Is your RV a caravan or motorhome? I have a swift caravan and have done something similar but without using CCGX screen, as I'm happy using the bluetooth App on my phone. There is a way to use the BMV 712 as a relay to switch on/off for voltage protection, just am not sure how it works.

I have attached my drawing for info

cheers

Stedoc00106820190312092715.pdf


doc00106820190312092715.pdf (145.7 KiB)
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drivebywire avatar image drivebywire commented ·

Hi Ste,

it will be a caravan. Thank you for your drawing! Mine will be similar to this, with two 160Ah Lithium and a 12/3000/120/16 Multiplus. Charging will be done with a 50A B2B Charger and 600wP of Solar, connected to a MPPT 100/50.

Since you are not using the CCGX, you can easily use the non-inverting VE-Direct cable. This port is used by the CCGX for me, so I cannot use that.

The most elegant way to control charge stop in case of cell over voltage would be to do it via VE.Direct from the CCGX; but sources in the internet indicate this does not work (see below). So, to be sure, I planned a Battery Protect to shut off the MPPT from the batteries...

All the best, Martin.

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drivebywire avatar image drivebywire commented ·

Ste,

you asked for a drawing.

Attached you can see my planned configuration. It is not complete yet - but I drawed it with real dimensions of the equipment, because I want to fit it in a certain space, and pre-mount the electrical components in the middle as one module, so I only have to connect input and output in the caravan.

You can see the basic components completely, but only 12V - without the B2B charger and the BMS / CCGX / VE.Direct connections.

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