Author Topic: Current Clamp  (Read 416 times)

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Offline monikaTopic starter

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Current Clamp
« on: July 18, 2024, 07:53:27 pm »
Hi,

I have a RS PRO RS CP-09 Current Clamp which is supposed to measure 0-200A with an Output signal of 1mV/A.

I have it connected to the voltage pins of a Fluke 115 multimeter and when clamped around a mains cable carrying around 10A, I don't get any any reading on the multimeter.  I have it set to the mV range.

Does anyone have any ideas why?  Could this be a faulty unit?

Thanks
 

Online Martin72

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Re: Current Clamp
« Reply #1 on: July 18, 2024, 08:08:28 pm »
Hi,

What did you set on the Fluke115, ac or dc mV?
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Online Gyro

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Re: Current Clamp
« Reply #2 on: July 18, 2024, 08:09:23 pm »
You need to be able to split out the individual cores of the mains cable, otherwise the current flowing through the Live wire and back through the Neutral wire cancel each other out, resulting in a zero reading.
Best Regards, Chris
 

Online TomKatt

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Re: Current Clamp
« Reply #3 on: July 18, 2024, 08:11:25 pm »
You need to be able to split out the individual cores of the mains cable, otherwise the current flowing through the Live wire and back through the Neutral wire cancel each other out, resulting in a zero reading.
This is probably the issue - are you clamping around a power cord that has multiple conductors inside?  You need to clamp around a single conductor.

Or use an AC adapter to split them out:
https://www.amazon.com/Line-Splitter-Klein-Tools-69409/dp/B01B7RTNSO
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Online Phil1977

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Re: Current Clamp
« Reply #4 on: July 18, 2024, 08:13:32 pm »
I assume you have set your multimeter to mV AC and that you are probing a single mains wire, not a mains cable with L and N.

Then I would check the banana plugs. Set the Fluke to resistance measurement, if you see nothing attached then probably the safety plugs are so safe that they don't make any contact at all. This is not so rare that safety plugs and safety jacks of different suppliers have problems.

 

Offline monikaTopic starter

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Re: Current Clamp
« Reply #5 on: July 19, 2024, 08:24:18 pm »
Hi,

Sorry should have said in my original post that these are individual cores and not a multicore cable ::)

I did find the solution in that it appears it was the multimeter sockets after all.  Despite trying another multimeter, I still had the same problem which led me to believe that it was a problem with the clamp alas it looks like an issue with the design of the sockets both were Fluke!!

Thanks all for your replies  ;D
 


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