RE: Five ways Fluke FieldSense technology can help you work safer

three-phase — Mon, 25 Mar 2019 22:35:10 GMT

Mmmm, I have read through this a few times now, and to be honest, I am struggling with some of your comments a bit. Whilst direct contact onto live terminals with test probes carries some risk, given the design of modern instrumentation, GS38 probe design with finger guards and IP2x terminations on equipment, the risk of an arc flash incident is minimal.

The manipulation of wires required to gain access with a non-contact fork can have risks that you have not mentioned. Manipulating wires close to a termination point could cause a wire to break or be pulled out of the terminal. Wire insulation can be damaged during installation that may only become apparent when someone manipulates the wire within an enclosure. For the panels I work in, 75 to 80% of the time I would need to manipulate the individual wire and or adjacent wires to get proper access for the fork.

You are also promoting a test procedure for measuring a voltage from phase to earth. For fault finding on circuits, the earth should not really be used for a reference point. The functional circuit is between phase to phase and / or phase to neutral, that is the voltage you should be predominantly interested in. When using the earth for reference, false readings can be obtained via return paths in circuits.

Phase to earth can be measured under some fault finding scenarios where phase to neutral is not producing the expected readings, but predominantly phase to earth measurements are made during a test for dead, or absence of voltage test. However, non-contact verification for an absence of voltage test should only ever be used in conjunction with a two probe tester and never instead of. To do so is fundamentally dangerous.

I do not have a T6 unit, so I have no specific experience with its use. I did buy a PRV240FS unit and it was not good. Battery life was very poor, four to six weeks. This in itself is a safety issue. Going out to a job and finding that you then need to return back to a workshop to get new batteries could lead to a scenario of an electrician not testing for dead correctly due to time pressures.

The comment regarding testing an instrument before measuring live voltages is an interesting one, and not something I had considered before - specifically measuring live voltages carries a different approach than testing for dead.

Whilst the T6 could prove to be useful under some circumstances, my experience tells me that those scenarios are limited and I seriously doubt that manipulating wiring can be considered safer than carrying out a traditional two probe voltage measurement.

Kind regards.