Measuring AC current with 60A probe (PP218)

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PatL
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Measuring AC current with 60A probe (PP218)

Post by PatL »

This is not an automotive system but out of curiosity I was trying to measure the current signal on a digitally controlled heat gun (Harbor Freight variable heat gun) using the 60A current probe. I ran into an interesting problem with the range settings that prevented me from seeing the negative side of the AC signal and it simply clipped the signal. The only range choices for the probe are -5A or higher (i.e. -5A to 60A or -5 to 30A, etc). I tried creating a custom probe with a +/- 30A range and the software would not let me. I ended up using the 600A probe to do the measurement and it worked fine.

Anyone know why the limitation on the negative side of the 60A probe? Seems like it would measure in either direction from zero the same.

Alan
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Re: Measuring AC current with 60A probe (PP218)

Post by Alan »

Hi,

The clamp can measure from -60A to +60A so there is no problem measuring the AC current from a hardware point of view. The presets you are using to scale / view the data however are designed for automotive use where currents tend to be DC - as such they are designed to show mostly positive currents.

Simply select the +-1V range and you will see the waveform just fine (10mV = 1Amp). If you want you can create a custom range / probe to display this in amps. Instructions are in the help manual.

PatL
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Re: Measuring AC current with 60A probe (PP218)

Post by PatL »

Thanks for the reply. I mentioned in my original post above that it would not let me create a custom range for the Amp probe below -5A. Makes no sense if the hardware is able to go +/- 60 A as I suspected.

Steve Smith
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Re: Measuring AC current with 60A probe (PP218)

Post by Steve Smith »

Hello Pat, I have just created a custom probe using the 60 amp current clamp in 60 amp mode. This will allow you to measure +- 60 amps on one scale. When editing a pre-set “automotive” probe click on the 60a Current Clamp (60A mode), then click “Duplicate”. This will duplicate the selected current clamp and place the clamp into the probe “Library”. Here you can then “edit” the settings for this probe with no fear of editing the settings of the original clamp. Scroll through the custom probe wizard until you arrive at the “Scaling Method” box. Click on the “Edit look up table” and erase the -50 value and type in -600, erase the -5 value and type in -60. Click OK and follow all the prompts to the end to click “finish”
Select this new probe from the probe library section under the channel options menu and select the relevant scale required. +-60 amp will be one of the options.
I hope this helps but please feedback if you need any further assistance.
Take care……Steve
Attachments
60A Current Clamp [60A Mode] (2).psprobe
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PatL
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Re: Measuring AC current with 60A probe (PP218)

Post by PatL »

Steve,

Thanks. The part I was missing was the scaling step. Got it now.

Pat

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