Ac line splitter + clamp meter help

Old 04-16-24, 10:05 PM
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Ac line splitter + clamp meter help

I would love some feedback as to what I am doing wrong using an AC line splitter and a clamp meter.
I am trying to determine the power consumption on some devices to determine back up inverter generator size. I am using a REED Instruments R5400 Line Splitter along with a EXTECH MA120: AC/DC Mini Clamp.
When I try to do a test I do not believe I am getting accurate results. I realize my clamp meter is not TRMS type and not sure if that will make the difference in obtaining more accurate results. I tried using the X10 slot on the AC line splitter to obtain more accurate results ( I realize that the X10 needs to be divided by 10 to obtain the correct result). One more thing I observed. When the clamp meter is held parallel to the ground I get one reading and when I let go of the clamp meter that is still attached to the AC line splitter and the clamp meter is horizontal to the ground I obtain a lower result. Any idea why that would happen

Old 04-17-24, 04:47 AM
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X10 yields more resolution, not more accuracy. Since parallel and horizontal to ground are the same, my guess is you are squeezing the jaws when holding the clamp meter. Have you looked at a kill-a-watt meter as a second opinion?
Old 04-17-24, 09:58 AM
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Have you used to measure a known load? For example, a 100 watt incandescent lamp draws 0.83 Amps at 120 volts.
Old 04-17-24, 11:20 AM
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What current are you trying to measure? That meter's resolution is 100 ma, so if you are measuring small currents you are likely to see the reading bounce around. And clamp meters are affected by the position of the clamp arms in relation to the magnet field of the wire, so if you move the meter around in the opening of the line splitter, the reading will change a little. That may explain why your reading varies depending on how you hold the meters.

Old 04-17-24, 04:55 PM
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That meter is not a TRMS meter because it doesn't measure voltage. It only measures current.

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