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Products => Test Equipment => Topic started by: AwaisN on August 23, 2018, 06:10:24 pm

Title: UNI-T UT202 clamp meter not measuring correct AC voltages and current
Post by: AwaisN on August 23, 2018, 06:10:24 pm

Hi,

I have UNI-T UT202 AC clamp meter. Few days back when I tried to measure AC voltages and current, it gave wrong readings as compared to Fluke clamp meter. I need calibration procedure for this UT202 and will appreciate if get schematic also. Temperature readings also need to be calibrated. DC voltages and resistance measurements seems ok.

Thanks and regards,
Awais

Title: Re: UNI-T UT202 clamp meter not measuring correct AC voltages and current
Post by: HKJ on August 23, 2018, 06:29:26 pm

Are you sure you are using the meter correctly?

There are some issues with thermocouplers and multimeters: https://lygte-info.dk/info/DMMThermocouplers%20UK.html
The clamp do not measure true rms, could that be the problem?

Title: Re: UNI-T UT202 clamp meter not measuring correct AC voltages and current
Post by: AwaisN on August 23, 2018, 06:57:45 pm

Yes. Before it was giving correct readings.

Title: Re: UNI-T UT202 clamp meter not measuring correct AC voltages and current
Post by: retiredcaps on August 23, 2018, 07:30:20 pm

How far off are the readings?  Provide examples please.

Title: Re: UNI-T UT202 clamp meter not measuring correct AC voltages and current
Post by: AwaisN on August 24, 2018, 07:36:55 am

Here are some measurement results for 50 Hz line voltages and AC Induction Motor Current.

From Fluke 322 Clamp Meter: 226.7 Vac, 116.5 Vac and 3.25 Amperes
From UNI-T UT202:                 Fluctuate b/w Overflow and random reading against 226.7 V from Fluke,
                                              106.7 Vac against 116.5 Vac from Fluke
                                              1.889 A against 3.25 A from Fluke