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Physics Bob: There are lots of DC clamp ammeters on the market. You simply clamp it across the +cable and it gives you a reading. I use it on cars and trucks to check all for all kinds of electric problems.

Bob

Yes I see that, when I reviewed them a little over a year ago The only DC clamp DMMs were over $200 and not very reliable, and were only for high currents not the 1 or 2 amps we are talking here. Things have changed since them, I will have to get one to try out. Our students like to blow the fuses when they measure current, they hook the DMM up wrong. We sometimes go through 60 or 70 fuses some weeks. We have taken to cutting a hole in the back of the meters so we can change the fuse without taking the meter apart.

physicsbob wrote:Yes I see that, when I reviewed them a little over a year ago The only DC clamp DMMs were over $200 and not very reliable, and were only for high currents not the 1 or 2 amps we are talking here. Things have changed since them, I will have to get one to try out.

I've got an amp clamp I've had since 1984. Was it George Orwell who wrote about how the world would change in 1984.

I guess we will neva no the why of the amps.

physicsbob wrote: Our students like to blow the fuses when they measure current, they hook the DMM up wrong. We sometimes go through 60 or 70 fuses some weeks. We have taken to cutting a hole in the back of the meters so we can change the fuse without taking the meter apart.

why not simply install a fuseholder in the test leads? duh

physicsbob wrote:Yes I see that, when I reviewed them a little over a year ago The only DC clamp DMMs were over $200 and not very reliable, and were only for high currents not the 1 or 2 amps we are talking here. Things have changed since them, I will have to get one to try out. Our students like to blow the fuses when they measure current, they hook the DMM up wrong. We sometimes go through 60 or 70 fuses some weeks. We have taken to cutting a hole in the back of the meters so we can change the fuse without taking the meter apart.

My DMM, doesn't blow over hooking it to the wrong way, it blows from hooking it up to a load that exceeds its rating. I've never blown a fuse in it in 15 years, I guess I had a better teacher or I learned better. Could be because I was self taught! Jim