Heard about this from someone who attended the recent AFCOM conference (hey, where are the trip reports from those who went??). Megger has a new amp-clamp style meter that can measure an intact power cord -- no need to separate the wires. Dunno how it works, but it has a slick self-centering mechanism, which should certainly help reading accuracy and consistency. About $250.
Been using this for about a year and I have been having some problems believing the readings on this device. I was looking around for reviews but can't find much. I am seeing a difference of about 50% between readings on this device and readings on dedicated single core CT meterers. It will often show an initial reading of (for example) 1.7 amps and then drop to 0.2 amps. When I know the reading should be around 0.5-0.6A. Now I am using it at the very low end for metering the usage on individual servers. To be honest I am very dissapointed with it. The manual say > 80% accuracy at 23 degrees C but I am not seeing that.
Anybody else having issues, or have a recommendation for a better unit that can do metering on multicore cables?
Originally Posted by hmsee1
We purchased three of the MMC850's and fielded them out to staff & electricians for evaluation. We compared the readings with a standard Fluke ammeter, with split or open power leads. Our results were not encouraging. We found that a large part of the time, the current readings were not on the mark.