This one was always in there also, and this is, of course, lockout-tagout. And then our live-dead-live step, so using the right category of meter, we would go ahead and verify that we were de-energized, and phase-to-phase, phase-to-ground. So make sure that that says zero, and test our meter before we do that verification step and after. And then, lastly, we always had this one, which... Well, this one's a little bit different. This one is some exceptions to that live-dead-live, so this is kind of new.
Exceptions to Live Dead Live
So exception number one, "An adequately rated, permanently mounted test device shall be permitted to be used to verify the absence of voltage." Okay, so that means that I do not have to have a qualified worker go into that piece of equipment and actually use a meter. I can permanently mount a test device in that meter, and I'm going to show you a picture of this right after this slide. But we do have to meet some requirements, right? So it is permanently mounted and installed in accordance with the manufacturer's instructions, test the conductors and parts at the point of work, where we're going to be working, has to be listed and labeled for the purpose of verifying the absence of voltage. It does the same thing that we would do if we were doing it manually. It tests each phase conductor, phase-to-phase and phase-to-ground, and the test voltage is verified as operating satisfactorily on any known voltage source before and after verifying the absence of voltage. So, basically, this device does the exact same thing that we would do if we were doing it manually.
And here's what it looks like, just one manufacturer of these. There's a lot of... Almost every company has these now. So this can be permanently mounted inside of a piece of equipment. It verifies it's working properly before it goes ahead and tests phase-to-phase and phase-to-ground. And then it verifies it's working properly afterwards, and it gives you an indication. You will get an indication right here when it is safe to work on that piece of equipment. So that is excellent. That could save our technicians from having to put on a lot of extra personal protective equipment.
What is an Absence of Voltage Tester
And to give you a little bit of idea about these, they are permanently mounted test devices, and they can do AC or DC, and really it takes away the chance of having an operator error. They are listed. The UL standard for these is 1436, new product category, and they've been out now about for a year. So NFPA 70E recognized those, and that's a great proposal.
And the last step, of course, has always been in there. Also, this used to be step number six. It's now step number eight. If we do have the possibility of induction or capacitance, then we would have to put ground straps on. They gave us some new definitions also, and they did a good job with this, I believe. A lot of the terminology in 2015 might have said, "Short-circuit current." Well, now they really want to get to fault current to include, not just short-circuits, but also ground faults. So available fault current, the largest amount of current capable of being delivered at a point on the system.
And so we'll take a look at what they gave us for new for these definitions, which is a diagram. So now you can see that this would be right in article 100 right near these definitions when we get our document in our hands. And we have a source, so whatever that source might be, that source, of course, could be the utility, it could be a photovoltaic system, it could be our generator, whatever. Fuel cells now I noticed are becoming very popular. But then it gives us a little diagram to show us that the available fault current close to the source, of course, is probably the highest it's going to be, and then basically, when it gets down into the equipment, it could, become lower as we add impedance to that circuit. Also, gives us an idea about short-circuit current rating for our equipment to make sure that it is rated higher than the available fault current. Talks a little bit about interrupting rating so that our overcurrent device can have a higher interrupting rating than the available fault current. So very nice that they put this in, and they've done a lot in this document with fault currents, so very good that they gave us a nice diagram here.