DIY Lithium

xsilvergs

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I would say the relays will stay latched to whatever their state was when signal goes (they would not be checking for signal status).

I can't see that much value in having a remote system that would only work when you are there though?
It would be a bit like a gadget I tried that allowed me to turn the awning lights on and off with an Alexa command - kind of fun in a "look what I can do" way but it was a bit of a faff to setup each time when a simplier system would do the job better as there was no need for unattended turning on of the lights :)

How about a Cerbo or late Venus GX running Node-Red? That would give control from any device, it could also check for internet connectivity and if none carry out certain rules.
 

wildebus

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How about a Cerbo or late Venus GX running Node-Red? That would give control from any device, it could also check for internet connectivity and if none carry out certain rules.
That would be a better out-the-box option but I was thinking a lower-cost solution was wanted? :)
 

Derekoak

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Ok so you were suggesting a remote system ONLY really that is why you were suggesting another sim always in the car. So yes not a lot of use, unless I did find a need to find the status and make changes while we are away tent camping say? Then I would need the more expensive victron bmv solution to give remote Soc status too? My bluetooth Bms us no use at any distance.
My first need however is automation of control while I am there. I suspect the ring b2b will do the job badly and might need amending preferably not manually.
 

xsilvergs

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That would be a better out-the-box option but I was thinking a lower-cost solution was wanted? :)

You can't get much cheaper than a Raspberry Pi in place of a GX. If you have a GX device Node-Red can run on a standalone RPi and send/receive commands to/from the GX, it can also drive relays off GPIO pins.

Best plan is to live in the van.
 

wildebus

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You can't get much cheaper than a Raspberry Pi in place of a GX. If you have a GX device Node-Red can run on a standalone RPi and send/receive commands to/from the GX, it can also drive relays off GPIO pins.

Best plan is to live in the van.
I thought you were suggesting getting a physical Cerbo GX or Venus GX rather than a Venus OS compatible device.
An RPi running Venus OS (#295) would work well.
 

Petes

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This is day two of LiFePO4's and the first day the sun has really shone. Looking at this I would think the BMS has shut down at 100% SoC at around 10:00, the MPPT went into Absorption with zero current flow showing, then at around 12:00 it went into float. At the point the current went to zero the battery voltage was about 14.3V. Or is that the 14.4V the MPPT is set at?

Am I correct?

So little point in having an Absorption over 14.3V?

View attachment 96201
I think your abolutley right which is why I have my Absorption level at 14.2 and float at 13.5, recommended to me by the battery supplier. I am considering turning off the solar controller when its in storage for 6 days at a time just to make sure I do take current from the battery, I seem to be taking around 5Ah a day at the moment with my monitoring but this will go up shortly when I visit the van and turn on the starter battery maintenance.
 

Derekoak

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You can't get much cheaper than a Raspberry Pi in place of a GX. If you have a GX device Node-Red can run on a standalone RPi and send/receive commands to/from the GX, it can also drive relays off GPIO pins.

Best plan is to live in the van.
Most of the time we would live in the camper whilst we were away. Mostly out during the day. I imagine 3 modes really needing different rules.
I) is living in the camper, out or in during the day
2) would be away for an overnight or longer with the fridge on everthing else off , during being away
3 is what is happening now , camper nearly all electrics off, car still driven.
What I want is a way for the SOC to control charging, at different levels with those 3 modes.
If I have relays worked by wired switches one the solar and alternator feeds to the b2b and look up SOC on the BMS and work the switches accordingly that is cheap but takes brainspace. It might be fine for mode 3. Anything you can suggest to automate this system more than that cheaply would be great!
 

Derekoak

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I have avoided Radpberry Pi as my son told me that you needed programming to do anything with them. I expect I could learn but last time was 50 years ago at Uni with fortran and punched cards. Except tiny bits in microsoft C:
 

SquirrellCook

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One thing I have learnt over the years, is that if you don't have it, it can't go wrong. This is reading like a post to promote tears, at worst divorce. Imagine what would happen if your gadgets ruin your beloved holiday?
 

wildebus

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I have avoided Radpberry Pi as my son told me that you needed programming to do anything with them. I expect I could learn but last time was 50 years ago at Uni with fortran and punched cards. Except tiny bits in microsoft C:
What I can tell you is that some South African dude did all the "heavy lifting" when it comes to programming a Raspberry Pi with the Victron Operating System. This means that now you can follow some very clear instruction and you will have the Pi working within a couple of hours without the need to touch any code.

I don't tend to do any coding either - the last time would have been mid-90's editing Windows source files to add extra hardware support.
 

Derekoak

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What I can tell you is that some South African dude did all the "heavy lifting" when it comes to programming a Raspberry Pi with the Victron Operating System. This means that now you can follow some very clear instruction and you will have the Pi working within a couple of hours without the need to touch any code.

I don't tend to do any coding either - the last time would have been mid-90's editing Windows source files to add extra hardware support.
That is good news, so having gone back and googled all the intials you and xsilvergs used and realised that RPi was an obvious shortening I can see that I could do that. (Probably).
Some RPi have blue tooth and wifi, does that mean I could pick up data from my bms, like SOC , and activate a 12 volt power relay based on that info? I assume a 12 volt relay will switch with a 3.3v or 5 v signal current?
 

wildebus

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That is good news, so having gone back and googled all the intials you and xsilvergs used and realised that RPi was an obvious shortening I can see that I could do that. (Probably).
Some RPi have blue tooth and wifi, does that mean I could pick up data from my bms, like SOC , and activate a 12 volt power relay based on that info? I assume a 12 volt relay will switch with a 3.3v or 5 v signal current?
xsilvergs has done a lot of coding to his setup, 'cos he has the know-how to do so and had got some great extra things available.

However, that is not needed if you can't or don't want to.
I took the Raspberry Pi and just loaded the Victron image on it and left it at that. What I like about being able to do that is that even though it is not a Victron product, the Victron image and updates work on it without any faffing.
I updated the Venus OS on it just this weekend and all I did was click the option to do an on-line update. So now running v 2.65, previously was 2.57, and can switch between them without having to mod anything.
1618214077441.png

considering the Venus OS is provided FOC and the VRM is FOC, I think personally that is outstanding!

right now all I have on the RPi is a SmartShunt SOC Monitor (I am using this to regenerate a Battery so all I need).
1618214350138.png

In a similar setup I did have a BMV-712 SOC and I used the integrated relay on the 712 to switch an SSR (240V Solid State Relay) on. So using the 12V enabling line to turn on/off the SSR. and a Mains Charger was plugged into the SSR.
I had the 712's Relay configured in the settings so it would turn on if the Batteries SOC dropped below a certain SOC, and also if the Auxiliary Voltage (usually the starter, but I had it on a different battery) dropped below a certain voltage.
So we had the automated/unattended aspect of remote-controlling a charger - but via VRM I could monitor the info and also override the 712 relay if I wanted to force the charger on (or off). Flexibility :)
You still need an SOC monitor - the RPi is not a monitor (nor are the Victron Venus, CCGX or Cerbo units) which is why there is a Victron SmartShunt connected in the above screengrab to provide that info.

If you were looking at a Victron type control/monitoring solution, when looking at the Raspberry Pi's I would stick to what has been used for this by others already rather then going 'latest and greatest' if the idea is to just have it work without too much messing. I've used the Pi 3 Model B+ (https://amzn.to/3t5R0f7), added in the heatsink kits and a casing plus a USB supply delivering 3A (here is an example - https://amzn.to/3a3VQC7 ). Then add in a Victron BMV-712 (that is the only battery monitor model that includes a programmable relay and a Victron VE.Direct to USB cable. That lot above would cost around £250.

You could subsitute the BMV-712 for a SmartShunt (save £80 or so) and replace the RPi with a Venus GX (which has other features including its own programmable relay plus a remote-controlled but unprogrammable 2nd relay) - that would be more money overall but would give you more flexibility.
I changed from an RPi to a Venus GX for the van and didn't regret doing so, but I still find the RPi great for smaller testing projects.
 
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Derekoak

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Did you get all those graphics you show from a smartshunt, or the RPi or something else?
Thanks I am preparing eventualities for when my kit arrives. So I am not buying anything yet or any time soon. The raspberry Pi looks very useful. The victron stuff is where the expense is. It is a shame. The Daly Bms has the SOC all worked out but not in a form that will work relays.
The Daly BMS comes with Uart which is a comms port. There are internet links about uart communication with Raspberry Pi. So very clever people ought to be able to get the SOC data to the RPi and activate relays. There is bits of info here https://diysolarforum.com/threads/new-daly-smart-bms-w-communication-80-250a.7002/page-17
 

wildebus

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They are from Victrons VRM service - Here is a link to a demo set of installations ... https://vrm.victronenergy.com/installation-overview

Depending on what you have setup, you can see different things. This is my overview screen in the Motorhome:
1618236626943.png

So I see the Battery SOC, the DC Load, the AC Load, what the Solar is doing, what the AC in current is in (my EHU is unplugged), what mode the Chargers are in, 4 different temperatures, weather and a map of where you are (you can setup a Geofence and get an alarm if the vehicle moves outside the fence - handy for off-site storage maybe?).
As I said, may not be for everyone, but I find it interesting for myself (I love analysing numbers!) and useful for testing/validating stuff (probably paid for itself in the extra info I have gleaned and fed back).
 

Derekoak

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So the graphics are from data picked up by the smartshunt and also picked up from the internet, organised by the VRM software loaded on the RPi and shown on a monitor you have connected to the RPi,?as the RPi has no keyboard, mouse or monitor itself. I apparently could link it to my android tablet via usb.
 

Nabsim

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So the graphics are from data picked up by the smartshunt and also picked up from the internet, organised by the VRM software loaded on the RPi and shown on a monitor you have connected to the RPi,?as the RPi has no keyboard, mouse or monitor itself. I apparently could link it to my android tablet via usb.
Dave has a lot of Victron Bluetooth kit so he has more data coming in than just the smart shunt. Let someone who knows this stuff more say for sure but I think what you have from the daly bms is the equivalent of the smart shunt. You would need to get that talking to something that can also talk to B2B, mains chargers, mppt etc if you wanted what Dave has
 

wildebus

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So the graphics are from data picked up by the smartshunt and also picked up from the internet, organised by the VRM software loaded on the RPi and shown on a monitor you have connected to the RPi,?as the RPi has no keyboard, mouse or monitor itself. I apparently could link it to my android tablet via usb.
nope, the VRM is a cloud service run/maintained by Victron and accessed via a browser - so you use any intenet connected device to view - PC, phone, tablet, whatever (except the Amazon Firestick - that DOESN'T work for some reason!).
If the RPi (or other Venus OS device) is not connected to the Interent, you can connect to it via the local intranet by putting in the IP address and accesing the Remote Console, which will give you "instant point-in-time" data (VRM is historical as well as instant)
1618239744921.png
 

wildebus

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Dave has a lot of Victron Bluetooth kit so he has more data coming in than just the smart shunt. Let someone who knows this stuff more say for sure but I think what you have from the daly bms is the equivalent of the smart shunt. You would need to get that talking to something that can also talk to B2B, mains chargers, mppt etc if you wanted what Dave has
yup. The Aardvark is just a Shunt connected. the Cheyene has a few more things in there.

I think the key is getting the BMS info out into the wider world. There has been talk for years of the IoT (Internet of Things) where everything is connected but right now they are all in their own private bubbles :(
I don't know (I suspect noT) if the Daly will do anything other than talk to its own app. Needs a clever programmer to break into it (and that isn't me, I know that :D )
 

xsilvergs

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That is good news, so having gone back and googled all the intials you and xsilvergs used and realised that RPi was an obvious shortening I can see that I could do that. (Probably).
Some RPi have blue tooth and wifi, does that mean I could pick up data from my bms, like SOC , and activate a 12 volt power relay based on that info? I assume a 12 volt relay will switch with a 3.3v or 5 v signal current?
@Derekoak and anyone else.

If you're interested in using RPi buy an RPi 4 model B. Download an image from here https://www.dropbox.com/sh/i8ru22o4ydws1rx/AADpa8lj5s2APZ2JS78OGPjKa?dl=0

You also need a VE.Direct to USB dongle (~£25 each) for each Victron device you have with VE.Direct.

For info ONLY look here https://flows.nodered.org/node/@victronenergy/node-red-contrib-victron to see the nodes available. The nodes allow easy reading of the VE.Direct data.

If you have further questions please ask.
 

Derekoak

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Looking more I will have monitoring with the daly app. what I am short of is as you say " getting the BMS info out into the wider world." Until someone hacks the Daly BMS!
Despite its cost the only way to get automatic action seems to be the victron bmv 712 with its programmable relay, with added Ve direct to usb. Is the RPi just for setup of the bmv and better monitoring than the little bmv screen
 
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