Any electronics engineers here?

Dan!

Member
Messages
3,029
Can anyone help me in coming up with a solution for amplifying a signal from a CT clamp mounted on a domestic power supply in the meter cupboard that needs to send a signal along 40m of 56amp triple core armoured cable?
https://savememoney.ie/shop/product/solar-edge-100a-ct-clamp/

We have a solar system installed where there are 18 panels on a shed 40 meters from the main house.
The invertor and 2x 2.4kw batteries are all located in the shed and the installer has connected the CT clamp to the fuse board in the shed… obviously this doesn’t give a true reading and also means that it can never tell when the house is calling for energy as it’s only measuring the current flowing to and from the shed!! The CT clamp obviously needs to go between the electricity meter and the main distribution board for it to work properly.

So here’s the challenge… as luck would have it there is a spare triple core armoured cable running from the meter cupboard, 40m underground to the very corner of the shed where the inverter is mounted.
So we could mount the CT clamp in the meter cupboard and use the armoured cable as an extension lead between the meter cupboard and the invertor, problem solved!
However, my concern is that the signal from the CT clamp will not be strong enough to travel 40m through 56amp armoured cable, given that it would normally travel through CAT 5 cable.. Would you agree, or do you think it would be fine?

If you agree that it won’t be strong enough, how would you suggest we amplify the signal?
 

allandwf

Member
Messages
10,995
What is the resistance of 56amp triple over 40m? I would have thought only a couple of ohms if that.
 

Dan!

Member
Messages
3,029
Thanks Martin, but that looks to be essentially the same as the one in my post. I agree with voltage drop etc.
I've reached out to some industry contacts as well, so fingers crossed someone will come up with a cunning plan.
 

Dan!

Member
Messages
3,029
What is the resistance of 56amp triple over 40m? I would have thought only a couple of ohms if that.
After messing about with an online calculator for these things, it looks like possibly only a 1% voltage drop.
So it might be worth trying it as is and see what happens... who knows, it may even work :)
 

Ebenezer

Member
Messages
4,521
I too have an electronics engineering degree, but have no clue about how electronics works. Reference the dads net thread, I had an education but it's questionable as to whether I'm educated!

What is a CT Clamp and why do you need one? Hoping to be educated.
Eb
 

Wanderer

Member
Messages
5,791
I am happy to use electronics - but I've not idea how it works, like Blackadder with cotton....
 

Zep

Moderator
Messages
9,302
What is the resistance of 56amp triple over 40m? I would have thought only a couple of ohms if that.

This - it depends on the CT signal and the cable size. You could use a signal conditioner to allow longer cable length / resistance.