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Fitting the CT Sensor for Solar PV kit

Hello All,

I have just received my Solar PV bundle. I was looking at my fuse board and trying to work out the best place to fit my Solar PV sensor. I have a type 2 kind of installation and I need some help in figuring out where to place the CT clamp monitoring the Solar PV.
I have read the guide and my feeling is that the wire that looks like the most logical place for me to attach the clamp is possibly a twin core wire. Please see the attached photo.

Is the cable going into the isolator switch and export meter a suitable cable for monitoring Solar PV


Welcome, Amol, to OEM

That is the one you have labelled “Solar PV Input”?

That is almost certainly a 3-core cable and NOT a suitable place for your CT2.
You will need to fit CT2 inside your consumer unit, on the brown single-core cable going into the No.11 (Sola) circuit breaker.

Thank you Robert. I was afraid of that. I will get an electrician in to fit the CT clamp now. I am not confident enough to open up the fuse box and fit the clamp.

Apologies something just struck me again, Is the meter tail with the current CT clamp (for the Solar PV) a good place to fit the other CT clamp for monitoring incoming supply.

That is your main meter that’s fed by the supply company fuse and was there before the PV existed? Yes, that’s the correct place.

Looking at the photo, it seems that cable may be flat rather than round, in which case it’s probably T+E? Amol, the CT needs to go around a single conductor (one length of copper in some insulation). It will not work if the CT encloses two or three lengths of copper.

Are you referring to the cable that I told Amol WAS NOT SUITABLE? If so, what’s the point of your comment?

If you’re referring to the “IMPORT METER TAIL” on the photo, then three points:

  1. How legal is T&E on a meter tail,
  2. what is the existing C.T. doing if it is T&E, and
  3. what is the grey cable next to the c.t.?

See Section 2 here: Home Energy - Guide | OpenEnergyMonitor or here Solar PV - Guide | OpenEnergyMonitor, or even Learn | OpenEnergyMonitor

I’m referring to the cable you mentioned in the post immediately above mine. Sorry, I thought I had replied to your message, but apparently not :frowning:

[ edit: I definitely did reply to your message this time. The ambiguity is not my fault; it’s down to lack of functionality in the forum software ]

And I’m simply making an observation and trying to double-check that Amol configures the system properly, since they don’t appear to know all that much about it. The photo doesn’t show the cable clearly and nor does it show exactly what the CT is clamped around.

Can you clarify? I’ve never noticed a post of mine not appear pretty much instantly, and you’re at Trust Level 2 so there shouldn’t be a reason for any post of yours to be held up. And if it had been, I’m fairly certain one of us would have released it. If you’re convinced there’s a problem, the Discourse forum is the place to raise it, maybe after consultation with G&T.

Nothing to do with any delays. I click on the reply button at the bottom of your post (not the reply button at the bottom of the thread). That should link my reply to your post - in fact I think it used to do so - but it’s not working at present. Saves quoting the whole of a post.

This is a reply to your 26 May 2021 20:49 (post no.10) and it says so for me while I’m typing it.

And this is a reply to your post no.8.

It looks the same to me typing it.

My theory is, if there are intervening posts, the “Reply to” relationship might be shown differently.
[Edit] And that indeed seems to be the case. Is that the answer to your impression that it’s “not working”?

It’s working for me too.

To the best of my recollection, simply clicking the reply in the post (the one djh referred to)
doesn’t automatically generate the quoted text. I’ve always had to highlight the text I want to
quote, then click the quote button that pops up.