How to position CT clamps correctly so solar does not interfere with EV charger.

[rwdl1984]

We recently had a solar panel system put it in. The solar batteries were delayed and put in after, at which point it became clear that the CT clamp for the solar system was positioned on the wrong cable. The inverter was reading the power generated by the solar system and including it in the house load, causing the batteries to discharge rapidly etc etc.

The solar company (finally) came back and moved the CT clamp to live 1 between the fuse and meter. This sorted out the issue with the inverter and batteries. Sadly, it has caused issues with our existing EV charger. The EV charger ramps up to around 5.5 kW then cuts out. The electrician from the solar company positioned the solar CT clamp right above the EV CT on live 1. He mentioned briefly at the time that they might interfere with one another.

I'm posting this now because the solar company has gone AWOL and are refusing to come back to fix things. Perhaps there is a simple fix here, without me having to convince a new company to and fix this? Does anyone know the correct position for the solar CT clamp that won't cause the EV charger to cut-out?

I have already tried moving the solar CT clamp further up the cable away from the EV clamp (as suggested in other posts), but this has not made a difference. Please see the attached image. The blue circle at top right shows where the solar CT clamp was positioned originally by the company, but this resulted in incorrect power readings on the inverter. The two CT clamps are together on live 1 now, the EV one is the one below.

Any suggestions would be much appreciated!

 

[davesparks]

Hang on a moment. My brain is starting to hurt. Would that work?
if the line is in reverse does that nessisarily mean the neutral would be going the other way.

need to think about this one.

Yes the current in the neutral will be flowing in the opposite direction to the live.

 

[Deleted account]

Yes the current in the neutral will be flowing in the opposite direction to the live.

Don’t know where my brain is today.
Every action has an equal and opposite reaction. Basic physics

Yes electrons going out via the line tail need replacing Via the neutral.

cheers

 

[rwdl1984]

Thanks everyone for your help so far. Here's what I tried tonight:

I moved the solar CT clamp up to the green circle as suggested. This resulted in a house load reading of 0 kW (even though several things were running in the house), presumably because in that position the clamp is reading the power generated by the solar (it was night time, so nothing). This was the original issue we had with the CT clamp, it was reading the solar generation as house load and causing issues with fast battery discharge.

I then moved the solar CT clamp to the neutral cable after turning it around. I also kept it as far away from the EV clamp as possible. This resulted in a correct house load reading (same as before). However, when I switched the EV charger on, it ramped up to 7 kW and then cut out. I noticed that it did charge for about 20 seconds longer than with the solar clamp next to the EV clamp on live, but eventually cut out.

Is there the option to move the EV clamp somewhere else instead, and if so, to which position? It seems to me that the EV clamp has a less crucial role to play in all this (the EV charger just needs to switch on and stay on), whereas the solar CT clamp is crucial for the functionality of the entire renewable system.

I really appreciate this help guys! If you have any other ideas, I'd love to hear them!

 

[timhoward]

It seems to me that the EV clamp has a less crucial role to play in all this (the EV charger just needs to switch on and stay on),

The role is to ensure your total demand from the grid doesn’t exceed your supply’s capacity. It can be very important.
Have you tried turning the solar off and removing the solar CT clamp and then using the EVCP to prove there isn’t a fault with the EVCP?
A lot of CPs are 7kw so is it now reaching maximum power and then cutting out?
As far as I can see the EV clamp has to be there to measure grid import.

 

[BenCos18]

The role is to ensure your total demand from the grid doesn’t exceed your supply’s capacity. It can be very important.
Have you tried turning the solar off and removing the solar CT clamp and then using the EVCP to prove there isn’t a fault with the EVCP?
A lot of CPs are 7kw so is it now reaching maximum power and then cutting out?
As far as I can see the EV clamp has to be there to measure grid import.

yep the ct clamp does have to be there for it
It has to be at the point after the meter so it can measure the grid import to limit the supply to the charger if needed