size of the current clamp

I have just had a look at our electricity feed, and it is very cramped, I wonder if I can get the current clamp around one of the incoming cables. So could someone please tell me how big the current clamp is so I can try to figure out if it will fit.

Thanks a lot.

termeerh's picture

It fits easely around a 2,5 sq milimeter cable and a lot bigger. My clamp is build in but I think 8 mm diameter wil fit also.

egraaf's picture

well, I would like to know the exact outside size since there is very little room to work with, not so much the cable diameter. It looks like this:

The red and black cables are the incoming feed, and this is the only place it is exposed.

icarus75's picture

Hi egraaf,

A picture speaks a thousand words:
clamp dimensions

Bart.'s picture


i see on the picture a 50 Amps so its 5a max? Can i plug any other model?

Im in canada and we use 2 phases 120V.

my circuit box is 240V 200A (2 x 120V/100A) so i will need 2 sensors with 100A load each

icarus75's picture

We now have a batch of 100A, 250A and 500A clamps in stock. If you'd like a quote for your particular configuration, pleas contact us via the contact form.


WCG_SYD_GHD's picture

Hi Bart

Can you please confirm the max cable diameter for each of the current clamps?

From the image above, the 50A is obviously 10mm ... what is it for the others?

Thanks, Carl

icarus75's picture

Hi Carl,

Here's the max cable diameter for the different clamp types:
50A: 10mm
100A: 16mm
250A: 24mm
500A: 36mm


sebastien.otten's picture

What is the minimum resolution that it can mesure of each clamps?


gebhardm's picture

The Analog-to-Digital-Converter utilized (an ATmega168) has 10 bit resolution on which the 0 to xA are mapped; thus the theoretical maximum resolution is Line-voltage * maxAmpereOfClamp / 1024...

Box18's picture

This means 230V * 50A (clamp 50A-10mm) / 1024 = 11,23 VA Right?
So now the resolution minime of 11,23 VA what will means? Is it capable of mesure 0.1W stand-by or vampire energy consomption ?


Box18's picture

11.23 kVA

Fluc's picture

11,23 VA (VoltAmpére) is somehow equivalent to 11,23 W (Watt) if the load is pure resistive (example: incandescence light-bulbs and electrical heating). Otherwise it is dependent of the Cos phi (Power factor) of the installation.

PeteByr's picture

Sorry to hijack - may I ask 2 dumb questions about connecting the FLS01-50 CT to the FLM02A, please?
1. Is there a recommended maximum length of cable between the CT to the Flukso module? I want to run about four metres from the sensor to the unit.
2: can I monitor a DC power feed from a battery using the FLS01-50 CT?
Best regards

gebhardm's picture

...and no, you can't directly use another type of current clamp, for example one with hall sensor, to attach it to the FLM; the internal circuit is balanced to the specific impedance and voltage output of the offered clamps - you may alter this, of course, but...

PeteByr's picture

Thanks GebhardM,
I don't think I'm up to speed on trying to change the board configurations...Think I'll follow your first advice and try to find a shunt - maybe can get some sort of Arduino feed..
Did I see somewhere on the blog about a way to record DC using a pulse on inputs 3 - 5?