Re: CATIII & CATIV Metering Requirements
willram2
The ratings you are talking about have nothing to do with the cable testing. These ratings are for the safety measures that the meter offers to the person using the meter. The 4 zones which are I, II, III and IV, are distinguished by their location in the premise wiring and protection against the magnitude of transient voltage. Outside and service equipment for instance are zone IV, where equipment inside the building, such as a copy machine would be zone I.
The industry standard used to be IEC 348, which has been replaced with IEC 1010. A higher CAT number indicates an electrical environment with higher power available, larger short-circuit current available, and higher energy transients.
Todays better meters offer a range of protection. Be careful when purchasing this equipment because a manufacterur can claim to "design to" a standard with no independent verification. You should look for the UL or CSA label to make sure that the equipment has been properly listed.
These 'better' meters are more expensive, but your personal safety is more than worth it.
The proper use of meters is a very important subject that seems to be avoided in most instances.If you want more info, go to a site such as Fluke, or AEMC to view their info about this subject.
Good Luck
Pierre