new UT202A+ clamp meter - incorrect readings ?!

[mike_mike]

Hello! I have a new Unit UT202A+ clampmeter. I tested it and I found that the clamp does not work OK, because when I placed the masured wire right in the center of the clamp, then it reads, for example, 6A ac. But when I move the wire to the one of the extremities of the clamp then it shows me a difference of about 0.5-0.6A ac.
I found on various forums, than some of people said that this is normal and some people that this is not normal.
Please tell me what you think about this situation ?

[mike_mike]

I made a few more tests and I found that:
If I measure the current through the wire while powering a 220V AC/1000W heater which also has a fan:
1. With the wire on the upper side of the clamp I=4.710A
2. With the wire on the center side of the clamp I=4.660A
3. With the wire on the lower part of the clamp (the most close to the meters body) I=4.419A

If I just close the clamp to the wire, while powering the same load as above:
1. With the upper side of the clamp I read I=0.022A
2. With the center side of the clamp I read I=0.099A
3. With the center side of the clamp I read I=0.134A

Please have a look and tell me what you think ?

[Manul]

The wire must be passing through the inside of a closed clamp, like a rope through a ring. Some small errors are expected, clamp meter is not a precision instrument.

[Benta]

You do realise, that only ONE wire must go through the clamp, right? You need to split the power cable to do the measurement.

[mike_mike]

Yes, I measured the current by splitting the cable.

I am still a little bit confused, and I don't know why it shows different readings if I move the wire inside the clamp ?

[BeBuLamar]

The manual did say that you should have the wire at the center of the clamp. If you don't you get another 1% of inaccuracy although your readings show more than 1%.