Fluke PRV240 proving unit
The Fluke PRV240 is a small, portable voltage source used to verify that an electrical test tool is functioning before taking measurements on a live installation. It provides a known voltage of 240 V AC or DC, allowing for the practical "test before touch" verification that many professionals adhere to. In short, it offers a simple way to check your multimeter, current tester, or other test equipment without having to access the actual installation first.
This makes it particularly relevant when you want to ensure that your measuring equipment responds as it should, both before and after a live measurement. It is also practical because the voltage is activated inside the unit when the probes are inserted, avoiding unnecessary contact with live conductive surfaces.
The unit is usable with both high- and low-impedance instruments. It comes with a TPAK magnetic hanging strap and four AA batteries, so it's ready for immediate use. A single LED indicates when the output is active, making it very simple to work with in daily use.
If it suits the task, it's primarily about the need to verify test equipment in a consistent and controlled manner before starting actual measurements. It is not a measuring instrument in itself, but an aid to ensure that the equipment you are using actually works.
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