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Discuss Anyone know of a multicore clamp meter? in the Electrical Tools and Products area at ElectriciansForums.net

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Evening all
I find myself in need of a multicore current meter, much like the old Megger MMC850 (now sadly discontinued) for use at a data centre where I work. Anyone have any ideas at all, I'm stumped!
Megger stopped producing the MMC850 some years back (apparently due to lack of sales, somewhat surprisingly), and they're as rare as rocking horse sh!t to find used - I've tried.
It's for use in a rack by rack analysis in a computer room, so powering off and/or using specific test leads is a no-no.
So all suggestions gratefully received.
Cheers. :)


Arms Access
I read somewhere that meter didn't take on as to get a meaningful / consistent reading, the cable had to be positioned within a sweet spot within the jaw.

Perhaps if you detail what you are trying to achieve, there may be some other ideas thrown into the arena.

Not intentionally suggesting live working, however I'm guessing you have IEC60309 inlets on each server rack. Have you looked at the Fluke iFlex? Could you remove the cover of the inlet and use the iFlex around the line conductor? If so, you know you'll get an accurate reading, which I'm not sure you would with the MMC850.
I've got the Kyoritsu 4200 which does up to 30a apparently but have only used it for earth resistance so couldn't say if it's any good


Arms Access
I've got the Kyoritsu 4200 which does up to 30a apparently but have only used it for earth resistance so couldn't say if it's any good
Just had a quick look at the spec sheet, that doesn’t do what the OP is asking, the Megger 850 supposedly measures current by clamping all cores, as opposed to the normal way of clamping just the line, as with any standard clamp meter.
The Megger MMC850 did give variable results, but if you were careful to rotate the cord within the jaws it was easy to figure the maximum/actual current being drawn. I had one for use in the data centres I was responsible for. A good bit of kit and very handy for certain situations.

I'm not aware of any replacement with the same capability, so setting up a search on eBay to alert you any second hand ones being sold might be the only option.You might also search for the Megger Flexiclamp, which was its predecessor and had the same capability to measure the current in multicore cables.
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Thanks for all the input to date guys - much appreciated. I wanted to use this to test draw on both the feeds going into rack PDUs, and also the individual kettle leads going to each server/cpu/switch in the racks, and as I said, powering down isn't an option.

Seems as though I may just need to make a break out box up with a panel mounted energy meter on it, with through leads. The items in the racks are almost exclusively dual fed, so could do this without too much drama, as long as it wasn't left single fed for any duration.

Again, thanks for all the comments. :blush:

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