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Multimeter CAT II Rating Discontinuation

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Fungus:
Getting back on topic, the confusion above clearly shows that every outlet should be approached as if it were CAT III.

(hence all the rules of thumb being posted here)

It's also not impossible that a plugged-in device very close to a distribution panel is CAT III, depending on the power cable, etc.

That's why I say CAT II multimeters are pointless.

Someone:

--- Quote from: bdunham7 on July 24, 2023, 11:19:46 pm ---
--- Quote from: Someone on July 24, 2023, 11:12:19 pm ---The standards are extremely clear on where the different Measurement Categories apply, every single socket outlet is CAT III, things that plug into it are CAT II.
--- End quote ---
Your own linked reference doesn't say that.
--- End quote ---
Well done referring to a vague "reference" (you could have quoted but didn't). I've quoted AS61010 word for word
https://www.eevblog.com/forum/testgear/is-cat-ii-a-useful-rating/msg4833239/#msg4833239


--- Quote from: Someone on July 24, 2023, 08:01:26 am ---Wow, another round of disinformation.

--- Quote from: Fungus on July 24, 2023, 07:03:37 am ---
--- Quote from: CosteC on July 24, 2023, 06:27:28 am ---CAT I was removed some time ago too.
--- End quote ---
"CAT I" is useful information - it lets you know the meter won't die if you apply the rated voltage with the meter set to Ohms (for example).

(assuming a CAT rating means "meter won't die at this voltage" - something else they ought to clarify in the standard
--- End quote ---
Measurement Categories I and II are not discontinued or removed, AS61010 still lists them as current:
https://infostore.saiglobal.com/en-us/standards/as-61010-1-2003-121163_saig_as_as_254253/
--- End quote ---

Someone:

--- Quote from: Fungus on July 25, 2023, 04:30:14 am ---
--- Quote from: Someone on July 24, 2023, 11:12:19 pm ---The standards are extremely clear on where the different Measurement Categories apply, every single socket outlet is CAT III

--- End quote ---

WRONG.
[screen shot of not a standard]

--- End quote ---
Well done, standards don't say what I can see they say because some other (non-standard document) says otherwise?

Kleinstein:

--- Quote from: Fungus on July 25, 2023, 05:13:31 am ---Getting back on topic, the confusion above clearly shows that every outlet should be approached as if it were CAT III.

(hence all the rules of thumb being posted here)

It's also not impossible that a plugged-in device very close to a distribution panel is CAT III, depending on the power cable, etc.

That's why I say CAT II multimeters are pointless.

--- End quote ---

I would consider an outlett so close (low impedance - not physical distance) to a major distribution panel more a problem with the installation, not such much a problem with the CAT2  meter category.
Such outlets should have some kind of warning lable and should be used with care.
I have seen the aftermath of a short (flash over in a failing light bulb) on such an installation ( some 2 m from a small breaker box and maybe 3-4 m from the distribution transformer). The 10 kA rated breaker  and GFI failed (closed), a 35 A and 100 A fuse blew and the 3x1.5 mm² cable to the outlett turned from gray to brown.

I see the higher CAT II ratings a bit pointless for a different reason:
Single phase mains is usually 110 V to 240 V nominal. Anything higher voltage (e.g. 480 V 3 phase outletts) tend to be no longer CAT II anyway.

Fungus:
This is going around in circles as usual.

Let's turn it around: Is there anybody here that thinks a CAT II multimeter makes any sense?

If not? Thread is finished.

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