Hi,

I have a multimeter where the 10A fuse has a description "10A max for 15min". Answers found online say this is the time it will take for the measurement components to return to thermal equilibrium hence an accurate measurement on the next test is made possible. Accuracy aside, will the unit be damaged if <10A flows continuously ignoring the cool down time entirely? The model # is 052-0060-2

An unrelated question: I fried my last multimeter by powering it via 9v SMPS and then trying to measure the voltage of the 9v source. Why? No 9v battery on hand. Reasoning suggests an intersecting ground loop was established as the unit and source were no longer isolated hence the need for a battery. I have a pocket scope powered off 9v barrel jack by design, is it wise then to switch to battery operated by soldering a pair of wires?

Happy Holidays
Mark

 

I once used my Beckman digital multimeter to measure a car's battery charging current directly. That wound up being more than the max 20 amps for quite a few seconds. After disconnecting, the meter continued to show current for quite a while, probably because it was so hot that the shunt arrangement was acting like a thermocouple.
For both metyer and scope, it is always a poor choice to connect the DC supply to any of the external connections. Many DC panel meters include a specific warning that doing that will cause destruction of the meter. ALL analog multimeters will be harmed if the voltmeter is used to check the resistance circuit battery while it is installed.

 

Accuracy aside, will the unit be damaged if <10A flows continuously ignoring the cool down time entirely?

I'd expect the meter to be able to do that.

 

I'd expect the meter to be able to do that.

I would presume that if there is a stated warning then certainly damage is at least possible, and more likely, quite probable.