Current Transformer for Multiplus II, what where how

[georgelza]

Hi guys

I happen to have a couple of these flying at home. how where would I connect them ? assuming they plug into the VenusGX.

G

[___]

30 minutes ago, georgelza said:

I happen to have a couple of these flying at home. how where would I connect them ? assuming they plug into the VenusGX.

Alrighty then, let me launch into some explanations of how the hardware works.

The Multi has a built-in current sensor on its AC input, and another one on its AC output, and from these two readings it can also estimate how much is going into or coming out of the batteries. Of course this sensor on the input of the Multi is rather inflexible, being built into the device and all, so what the designers did is make it possible to attach an external current sensor to the Mutltiplus-II that REPLACES the reading from the internal one.

Why is this important? When running ESS, the Multi tries to zero it's input (unless you use a modbus meter, but ignore that option for now). If you want it to also attempt zeroing out some grid-side loads (geyser, stove), or import the power made by a grid-tied inverter, you want to move this sensor to a point where it will see those loads/generators.

Now... ESS has always had the ability to compensate for such loads by using a modbus meter, but the optional external current sensor is a much cheaper option, and it gives you all the same features. The only downside is that it can't be installed very far from the inverter.

So you can't really use more than one in an installation (except if it is three phase), you can't use it to measure other loads, and you can't attach it to the Venus-GX. It is specifically made as an optional extra for the Multiplus-II.

Edited March 27, 2019 by plonkster

[georgelza]

Ok, got the clamp meter...

Can/will plug into Multiplus II (which will happen to be right next to my main DB)

... Around what lead do i clamp the SCT-013-0000 though, main Feed, after the CG. 

G

[___]

54 minutes ago, georgelza said:

... Around what lead do i clamp the SCT-013-0000 though, main Feed, after the CG. 

Wow, I just realised what you are saying. The current transformer for the MP-II is in fact a SCT-013-0000.

You don't need a Carlo Gavazzi meter if you use this. It has the same function.

You clamp this where you want the "Zero" point to be, generally right after your electricity meter, or for most people around the thick red cable that comes out of the main switch inside the main DB.

[VisN]

On 2019/03/27 at 10:28 AM, plonkster said:

Wow, I just realised what you are saying. The current transformer for the MP-II is in fact a SCT-013-0000.

You don't need a Carlo Gavazzi meter if you use this. It has the same function.

You clamp this where you want the "Zero" point to be, generally right after your electricity meter, or for most people around the thick red cable that comes out of the main switch inside the main DB.

Even cheaper here NON-INVASIVE AC CURRENT SENSOR (100A MAX). I just ordered one and seeing as I work within a few minutes of them, I can collect. 

[VisN]

Just collected mine. There seem to be 3 left on the site. Let me know if anyone would like me to collect and bring up to Johannesburg/Pretoria. I am in Midrand.

[VisN]

Has anyone successfully extended the lead on these SCT-013-0000s?