AC/DC clamp meter reccomendation

[petrolhead]

I only got the CPC flavoured one because I could at that time add it to an existing order with them, as such it was much cheaper than a UniT meter.

Well the CPC one costs £46.73 delivered next day (The currently cant guarantee it will ne next day tho)
The Uni at Amazon costs £48 delivered today

EDIT: I have just bought the one from Amazon

 

[petrolhead]

I recd the UNI-T and should I be dissapointed with my findings?

 

[voipio]

The elements in AC mains loads, like kettles and heaters, aren't exactly contructed to laboratory reference standards, plus the resistance of the element will increase as it heats up, plus there will be an error in the AC voltage measurement (+/-1% +3 digits), so the possible differences from expected values start to stack up. The heater load is not constant power. The power dissipated in the load will vary with supply voltage, so the P/V equation shouldn't be applied too literally in this case. The cable position in the clamp can also influence the measurement (ideally it is central and perpendicular), and strong magnetic fields close to the clamp will also influence the measurement. The spec for this meter on AC current clamp is +/-2.5% +8 digits. Overall, the observed values aren't too shoddy. Using an inline AC current meter to measure the actual current in the cable, would be a better way to measure the current for the purposes of a comparison.

 

[petrolhead]

Thanks, great mins think alike voipio

So I did another test using my trusty Fluke 115 Meter.

These are the results aginst the UNI-T

So not bad at all

I also found this YouTube video about the UNI-T

Far too techy for me tho

 

[voipio]

That's pretty good, really. The clamp meter calibraton assumes pure sinewave current, and the presence of mains harmonics will tend to cause an overestimation of the current, so a reading slightly over the inline Fluke on a "typical" mains supply is not unexpected.

 

[Robotstar5]

You are assuming the plated wattage is correct, measure the resistance and divide it into the voltage to give calculated current draw. V/R = I (amps)

 

[petrolhead]

You are assuming the plated wattage is correct, measure the resistance and divide it into the voltage to give calculated current draw. V/R = I (amps)

Crumbs now into OHMS law

I will have a look though out of interest and report back

EDIT:
750 = 69.2Kohm
1250 = 40.6Kohm
2000 = 25.9Kohm

 

[voipio]

Presumably those are Ohms, rather than kOhms, and will be the cold resistance values.

Is the test load an oil-filled convector?

 

[petrolhead]

Presumably those are Ohms, rather than kOhms, and will the the cold resistance values.

Is the test load an oil-filled convector?

Opps edited yes Ohms

Its one of these - here

 

[petrolhead]

Just wanted to say thanks for all the replies and help

 

[creepy]

Uni-T makes good stuff at reasonable prices.
I have this one https://www.ebay.co.uk/itm/283882488770

UT210E​

Which is great for automotive use as it has a 2A DC scale that I can pick up a 100ma parasitic drain with. Of course if you want it for household use then they have alternatives.

Mine arrived over the weekend, like it a lot thanks for the suggestion.