Electronic – Current measurement maximum time

current measurementmeasurementmultimeter

On my multimeter I have two current measurement connection. One for the mA and one for the A.
On the ampere one there's a time limitation but not on the mA one. Also they mention in the manual a kind of "cooldown time" after the measurement for the A one. So, basicaly, probing with this input can really slow down my project. (max 15 sec every 5 minutes)

My question is, I have to switch to that A one for a 600-700mA current (mA input is 500mA), as it's not a "big" current, can I bypass this limitation ? Is it design for higher current only or any measurement done on that input ? It's a middle-end multimeter but even the online datasheet is not complete about what. (Was excepting a kind of measured current/cooldown time graph)

Best Answer

A typical multimeter manual would say something like this:

Function Overload Protection               Overload 
mA       Fused, 440 mA, 1000 V FAST Fuse   600 mA overload for 2 minutes maximum, 
                                           10  minutes rest. 
A        Fused, 11 A, 1000 V FAST Fuse     20 A overload for 30 seconds maximum,
                                           10  minutes rest.

(example from Fluke 77-IV manual)

I guess the exact time allowed and rest time depend on the exact current and on environmental conditions too (ambient temperature etc). I've not seen more detailed information in any multimeter manual.

Multimeters are not really intended to be a permanent part of a high-current circuit.

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