question

sieade245 avatar image
sieade245 asked

Victron AC Current Sensor alternative

Hi. I want to add solar PV inverter power monitoring to my CCGX display. I have a Multiplus 3000/24. I've checked the serial number and I should be able to use the Victron AC current sensor. I'm already using the temperature compensation inputs for temperature compensation so was going to plug into the aux in.

My question: Does anybody know what the current sensor outputs ? Is it a voltage (eg 0-5V) relative to measure current with limits set up by the dip switches, or a 4-20ma current similar to water sensors etc or something else.

The reason I ask is that my whole system has been built from recycled batteries, used inverters etc. The only thing I had to buy new was the CCGX because I'm short on home time at the moment, I work away a lot and didn't have time to learn raspberry pi (YET!) . There are several alternative current sensors available which are much cheaper than the Victron unit. I realise that Victron need to make a decent profit on the accessories and where I work we exclusively buy new Victron equipment to the sum of several tens of thousands of pounds worth which I install so I do feel I support them best I can....but I'm on a tight budget here. This is just my home project to try and save the planet! :-)

Any help or information would be handy. Thanks

MultiPlus Quattro Inverter ChargerESS
3 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Guy Stewart (Victron Community Manager) avatar image Guy Stewart (Victron Community Manager) ♦♦ commented ·

Hi Sieade,

I am moving this question to the modifications space. Please read this thread for recent experience of a similar attempt, and Victron's subsequent policy about using unsupported 3rd party accessories with Victron equipment.

https://community.victronenergy.com/questions/9795/bluesolar-terrible-voltage-accuracy.html

Sometimes it works great and no problems, sometimes it leads to big headaches when things start behaving strangely and people come back to Victron for an explanation, or blaming the equipment for strange readings.

So we need to make it very clear that while we do not block these things, please understand that using other accessories means Victron cannot help with system support.

0 Likes 0 ·
sieade245 avatar image sieade245 Guy Stewart (Victron Community Manager) ♦♦ commented ·

Thanks Guy. This is a home project using very old batteries and inverter units. I wouldn't expect a shoulder to cry on if I blow it all up! More of a hobby I wouldn't dream of doing any of this crazy stuff with our professional installations.

0 Likes 0 ·
Jean Jacques de Jong avatar image Jean Jacques de Jong Guy Stewart (Victron Community Manager) ♦♦ commented ·

It is understandable that Victron cannot encourage or support using "unqualified" sensors, but can they not at least provide the specs for the adventurous? This would make Victron products even more attractive for the tinkerers out there. I have a bunch of current transformers lying around, and I'd like to "recycle" one to serve as an AC current sensor. Victron's AC current sensor looks very similar to a CT. I believe it's simply a CT feeding a resistor to convert the current to a voltage that can be measured by the AUX or Temperature sensor inputs, the value of that resistor being selected by the DIP switches. So, if the assumption is correct, what is the resistor value and the CT ratio?

0 Likes 0 ·
1 Answer
Paul B avatar image
Paul B answered ·

Hi there, Best way is to buy the victron AC current sensor, or take your chances and take a guess, or test one at work on the next install

1 comment
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

sieade245 avatar image sieade245 commented ·

Hi Paul. I was thinking if it can connect to the temp sense inputs then it must provide a signal similar to what the temp sensor does? I'm not sure if the temp sensor is a thermistor type where the resistance changes with temperature and then the multiplus uses this in line with another resistor in a resistor divider network to calculate voltage across the sensor and then temp...or it could be the current through the sensor changes with resistance and the multiplus measures this... I was hoping it was a voltage so 0-5V or similar. Might not even be a thermistor temp sensor though. I'll need to get more info....in fact this is related to the other question I asked today about the fronius inverter because if I can just fit a data logger..I won't need the AC current sensor as its only going to be used for measuring solar yield.


0 Likes 0 ·