I’m looking at upgrading my small loadshedding setup to a Multiplus II 48/3000/35-32 with Blue Nova RacPower 52V. My reading indicates that I will require a Victron GX device for CAN comms with the battery. Is there a way of doing this with a Raspberry Pi or is it an absolute necessity for a GX device?
If you already own a rPi, then it is an option and can be a little cheaper.
If you still need to buy a rPi, then it is 1) not really cheaper and 2) you can’t get rPi to buy.
With the Pi you need to get a lot of extra stuff and wiring that is already included in the GX device.
With the GX device you can connect the Multi II to the GX with a RJ45 network cable where with the Pi you need to use the USB-MK3 device (R1500).
For the battery you need to connect it with a CANbus. With the GX it is again just a RJ45 cable where with the Pi you need a CAN hat (Perhaps the CAN hat could work for the Multiplus as well??)
If you have SmartMPPT these need to be connected as well. With the GX the Ve.Direct cable is about R100, but with the Pi you need a USB->Ve.Direct that is about R400.
Then if you need stable power from the battery you need a good regulator that can take the input from your battery low/high voltage range and supply V5 3A. The GX already has this built in. If you use an AC 5V psu the pi will be off when your inverter is off, and you can’t start it until utilities is back online.
So you can use a Pi and it could be cheaper. But normally it is not cheaper by much once you add everything you need.
Yup. Just a Pi and a nice case puts you halfway to 2k. Add the CAN hat and now you’re a little over 2k. Add a good DC PSU, plus any of the cabling you need (eg the MK3-USB is on the other side of 1k), and you’re within spitting distance of 3.5k.
And then you still have to deal with SD-cards going bad… or spend even more money to get a better boot solution, which puts you at Cerbo-money, that also comes with a 5-year warranty. Plus, you can actually get one.
That’s what swayed me. I have a Pi running Venus, but still went with a Cerbo just because I remembered how annoying failing SD cards were when I used a Pi as a media PC.
Since I banned Samsung SD cards from my home and started using Sandisk extreme, I have not had any issues, and I have machines doing logging to SD cards that have been running 7+ years without issues. I think its because Sandisk actually implements some form of wear levelling, whereas Samsung subscribes to the policy that a broken SD = a new sale.
Also had better luck with Sandisk, but I have yet to see a hard-working SD-card make it to two years. They don’t last that long. It isn’t just the time they last that is irritating, it’s that they tend to fail at inopportune times. So they become maintenance items you have to do BEFORE it fails. You know, like water pumps on BMWs
This, so much this…
Most people are using SSD Drives on the rpi4 now…Much more reliable.
This is what prompted the question. My current small loadshed system is a Multiplus 12/800 with BlueNova battery, I already use a previously unused rPi running Venus on a Sandisk Extreme with the USB-MK3 for comms but no solar so none of the other paraphernalia. If the CAN hat is as scarce as the Pi at the moment then it is probably a non starter even if it was slightly cheaper.
I know the Multiplus II GX model powers the GX directly from the battery, how is an external GX Cerbo or suchlike powered?
Maybe I should flog the rPi to partially finance a GX…
But then what am I going to use when I get my feet wet with Node-Red…
Venus Large OS … it includes NodeRED.
Can you load it onto a Cerbo or suchlike?
Aaah… too quick on the draw
I’d already loaded the Venus large on the rPi but didn’t realise it could be done on a GX
Same OS, bar a few technical OS tweaks in the core to work on a RPI.
I would really sell the RPI and upgrade to a Cerbo … with 5 years warranty if you ever need it.
Yup, I’m starting to think the same.
Moving on to the classifieds now…
You can also sell this, can do everything from the Cerbo (Venus) now, don’t need that MK3 anymore.
This CAN HAT works on the pi if you want to keep what you have:
I have three MPPT’s and a Multiplus II on my 3B pi and the CAN HAT connects to my PylonTech battery bank
But once the system gets larger, a Cerbo is the way to go.
That’s good to know! Few questions:
- How long you been running it like this?
- How do you power your Pi?
- Any SD failures, or you running off SSD?
- How many Pylons?
- And the most important… how tricky to setup and configure, I’m from an IT infrastructure background so fairly savvy but by no means an expert.
Mmm, just read the spec again… is it compatible with a rPi 4 do you think?