[Antipodal]

Hi everyone . I bought yesterday this meter - for $5! It has  an ohms function which works and it has a volts function which works.It does not have an operating manual nor does there seem to be one on the internet . And sadly the current function , which was the main reason for buying it seems not to  work .I am not sure whether , on current function the power cable can just be encircled by the jaws or whether the jaws must actually  be opened and , on release actually pinch the cable  like a pair of  pliers.If anyone has had experience with this meter  and can offer any ideas on how to operate it on current function correctly or if they are familiar with it seeming not to work measuring current I'd be grateful to hear. Thanks everyone and cheers.

[DaleHCook]

The clamp should encircle just one conductor of the cable. The jaws must be closed when making the measurement.

[morzh]

as Dale has noticed, with some explanation:

The clamp is the core, making a current transformer.
It has to clamp around ONLY ONE wire (not, for example, the whole AC cable, as summary current will then measure Zero Amps). This one wire is the Primary winding of that transformer.
Inside the meter is the second winding, a milty-turn with Ohmic low-value load.
This is where the Voltage measured across that load as the proportional value to the current in the wire through the clamp. Then it is calibrated to show the Amps.

This is for the AC component.
If the clamp is DC-capable, the DC is measured by a Hall element.

In order for the transformer to work (that is the flux to circulate in the core) the clamp has to be closed. Else there is no core, no flux and no measurement.

[DaleHCook]

as Dale has noticed, with some explanation:

Thank you for providing that explanation. As I get older I tend to provide minimal explanations, when some members would benefit from a more expansive explanation.

[morzh]

My knees recently and my back (started at the same time, about a few months ago) persistently remind me that I ain't getting any younger either.

[Antipodal]

Thank you fellows ! Great result !I have made up an adapter from a piece of three core cable, separating the 3  insulated cables so that the jaws of the meter can  go round just one active one.  I plugged in a two bar electric heater to the adapter and measured the current - 5 amps with one bar turned on . Exactly as it should be . And thanks to  your generous explanations I have learned how it works. Thank you all.

[DaleHCook]

My knees recently and my back (started at the same time, about a few months ago) persistently remind me that I ain't getting any younger either.

With me it's my knees, my back, and my right hip (which, if I live much longer, will need a replacement). All of those began bothering me about five years ago. I have been through enough illness this century (some of which would likely have killed me in the early 1900s) that I consider myself fortunate to be in somewhat decrepit but otherwise healthy condition.

[Paul Philco322]

Phorum is the only place I know where we discuss renovating old electronics as well as old electronic renovators bodies! Good luck with both aspects of our hobby! Paul (a recent knee replacement Antique Radio Enthusiast)

[David]

You said active wire just to make sure. The wire the clamp goes around would be the one going to the breaker. Hope you are enjoying summer. David

[David]

Found some info at this link hope it helps. David    https://www.radiomuseum.org/r/kyoritsu_a...l_830.html

[morzh]

Dale


While i knew I had herniated discs (accidental discovery during an unrelated reasoned CT Scan some 6 years ago), none of it bothered me.
All started at my mom's place. Stress, then sleeping in a bed with a very different mattress. Both the knees and the back.
It's been 4 or so months since I came back, but the trouble stayed. Plus more.
Oh well...at least, when I wake up, I know I am alive.