Reinhard Zwirner wrote in message
...
N Cook schrieb:

Reinhard Zwirner wrote in message
...
...

Have a look at

www.gmc-instruments.com/english/produkte/metrahi2.htm

This DMM (obviously discontinued) and other types of that line
of GMC DMMs have a so called "Automatic Blocking System":
depending on the measuring range only the corresponding inputs
can be used - the other ones are blocked.

I don't know if Gossen Metrawatt's DMMs still have this feature.

HTH

Reinhard

I take it the 2 red rings on the lower line are shutters that slide away
when the probe plug is pushed into the relevant socket.

AFAIK the input sockets for measuring current are blocked mechanically
when the function/range selector is switched to voltage or resistance
measurement (and vice versa): it isn't possible to insert test leads
into the blocked sockets.

At the same time you can't switch to voltage (or resistance)
measurement if the test leads are still plugged into the current
measurement sockets.

It still leaves the possibility of thinking (or not thinking) that the
DMM
is , per usual, set for measuring voltage but is still set for current.

No, it wouldn't be possible to turn the function/range selector switch
to any voltage measurement range.

So far, the only retrofit add on I can think of, is a buzzer activated
on
inserting the probe plug in the current socket and beeps continuously
until
removed.

IMHO this wouldn't be necessary any more.

Regards

Reinhard

The point of my post/query was that someone, like me, using the same DMM day
in day out, 99.99 percent of the time for other than current, may accidently
go to use this meter , still set in amps mode, for measuring volts , just
because it is so ingrained in using it for such purposes.

Anyway, potential pitfall solved using Ron(UK) technique in this thread.


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