'Noisy' Loop Impedance Measurements with Fluke 1652?

[JohnW2]

Yes - it would actually be PEFC. It must assume you would know that to save a display digit.

Yes, that's probably the reason (given that the other thing it may display there, "PSC", has only three characters). However, it's not really 'wrong', is it, since "PFC" can be either PEFR or PSCC?

I don't know how it does it but it would be "the difference plus half of L-N" wouldn't it?

Indeed. I was a bit sloppy in not being explicit enough, but that's what I 'meant' (or, at least, was thinking!)

Does it display similar with the two-wire test? I can't remember - or have never noticed.

If one does a 'two-wire' (i.e "L-N") test, then there is (understandably!) no option to display Re, so the 'display changing' button does nothing. The only thing it can display, and does display, is "PSC".

I note there is a "PSC" display so it must show that even if you are measuring L-E. (I haven't looked at the instructions). It wouldn't know.

As above, it's either one or the other, according what sort of test (L-PE or L-N) one is doing. In the former case it can only be "PFC" (but that can be changed, with the button to Re), but in the later case, there is no option to have anything other than "PSC". That all makes sense.

Interesting. I was thinking that the machine would do both calculations but just display the one selected - perhaps not. So what would be the difference between the two?

Exactly. If it were doing exactly the same test, and measuring exactly the same things, every time, and all the button did was to determine which of the measured/calculated things (PFC or Re) was displayed, then exercising that choice (just of what was displayed) would not effect whether or not one got an Err5. I therefore can but presume that there must be some difference in what is actually done, not just in what is displayed.

Anyone else?!

Kind Regards, John

 

[JohnW2]

.... If it were doing exactly the same test, and measuring exactly the same things, every time, and all the button did was to determine which of the measured/calculated things (PFC or Re) was displayed, then exercising that choice (just of what was displayed) would not effect whether or not one got an Err5. I therefore can but presume that there must be some difference in what is actually done, not just in what is displayed.

I should have added ... there is another reason to suspect that, for whatever reason, the button is doing more than simply toggling the display between (already measured/calculated) PFC and Re.

If, have done a test and displayed Ze (plus either PFC or Re), one presses that button, it does not simply toggle the display to show the other result but, rather, takes one back to a 'blank' screen, ready to start another test. That again seems to suggest that the way the test is undertaken and/or the way the results are processed must differ according to whether one has chosen to display PPC or Re.

All rather odd, and 'unexpected'!

Kind Regards, John