Clamp Meter Recommendations

[fifty60]

I would like to get some recommendations for Clamp amp/voltage meters. The best one I can find now (and to quote from another forum) is "The F607. Very complete and still simple enough for a clanky to operate..... The good thing with the F607 is that you can also use it to measure actual grid frequency AND motor speed (small magnet on the shaft and pick up the field with the clamp. That is a very good way to see if the slip is too high. It checks harmonics, too."

Wow, what a meter. I would like to be able to measure motor rotation speed. We have a particular motor manufacturer who is telling me that their motors operate optimally at 115V whether they are supplied by 50 or 60Hz. I am not disputing that they operate at both frequencies at that Voltage, but that optimally we should drop the voltage with the frequency. We build our own enclosure and we overheat at 50Hz, so we would lower the voltage and do not have the problem.

Anywhow, I ran into that F607 and it looks like it would be a pretty great investment. $600 bucks though (with shipping). I would like to find another quality amp/volt clamp meter and I also want equipment to test induction motors. I would really like something to test the RPM. I've used a laser measuring device in the past but do not remember the name of it. What do you guys recommend?

 

[GoldDigger]

I would like to get some recommendations for Clamp amp/voltage meters. The best one I can find now (and to quote from another forum) is "The F607. Very complete and still simple enough for a clanky to operate..... The good thing with the F607 is that you can also use it to measure actual grid frequency AND motor speed (small magnet on the shaft and pick up the field with the clamp. That is a very good way to see if the slip is too high. It checks harmonics, too."

Wow, what a meter. I would like to be able to measure motor rotation speed. We have a particular motor manufacturer who is telling me that their motors operate optimally at 115V whether they are supplied by 50 or 60Hz. I am not disputing that they operate at both frequencies at that Voltage, but that optimally we should drop the voltage with the frequency. We build our own enclosure and we overheat at 50Hz, so we would lower the voltage and do not have the problem.

Anywhow, I ran into that F607 and it looks like it would be a pretty great investment. $600 bucks though (with shipping). I would like to find another quality amp/volt clamp meter and I also want equipment to test induction motors. I would really like something to test the RPM. I've used a laser measuring device in the past but do not remember the name of it. What do you guys recommend?

Does the F607 include a DC amps function using the clamp? With PV, EV charging, UPS backup power, etc. becoming more common, the ability to do a non-contact DC amp measurement is very useful.

 

[fifty60]

Is it possible to measure DC with a clamp? I thought the clamp was a transformer.

 

[GoldDigger]

Is it possible to measure DC with a clamp? I thought the clamp was a transformer.

In addition to the separate winding around the clamp core to make a current transformer, good only for AC, it is also possible to include a Hall Effect transducer as part of the core assembly so that you can measure the absolute magnetic field. This gives you a DC amp reading.
It is similar in a way to the magnet-based mechanical DC ammeter that you slip over a battery or starter cable, just far more precise.
The zero is less stable than with an AC reading, and it is sensitive to the earth's magnetic field and other stray fields, especially if the clamp is not perfectly closed.

You can get a cheap multimeter that includes DC amp clamp from Sears for about $60 in case your $600 meter cannot handle it.