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"You can't get rid of voltage " ..... I thought you knew what you were talking about but you've never heard of voltage drop

Thank you for sharing your knowledge

Thanks for sharing your knowledge.

Mike I have followed you from Apprentice to Journeyman to Master. Thank you for all the online support from your videos throughout the years. Also I wanted to ask your opinion on the explanation of the ground rod, because I get asked all the time. Why is it important to ground all equipment metal and whats the sole purpose of the 8ft rod. My explanation is this, so please tell me if Im wrong or right, I simply say, The grounding is a safety feature, at no time should any voltage should flow through it, and its also a default for the neutral wire, this is where the ground rod comes into play. The bonding of equipment and all metal will cause a short if the hot wire touches the metal enclosure and trip the breaker so that electricity will not flow through the metal whenever you go to casually or grip tight touch it, thats the safety part of it. The default for neutral part is that in the event when and if you loose neutral, possibly from the utility feed, then while electricity is trying to exit through the other phase causing the lights to go brighter and “surge”, the ground rod that is connected at the main panel to the neutral is suppressing the exit of electricity as best as possible and helping to eliminate a neutral feedback just in case you make contact with a neutral side of anything electrical. I know its sounds crazy but this is my theory on the actual reason the original plan for ground took place in the NEC book from the beginning. I could be wrong 🤷🏼‍♂️

I get for the purpose of this lecture you are using the 75C table , but code wise should you not be using the 60C table ? regardless of insulation rating , you are under 100 amp and unless the terminals on all sides are labeled to be rated above 60C you should be using 60 C table VD aside , to me this is 8 ga wire on a 50 .

The future does not contain A.C. it will all be low volt D.C.

Nice Good to know 💡 Mike

I agree that it meets code. However, your rationalization for the short circuit condition is a little out there. Go look up the response time of a breaker at rated amperage. It certainly won't be three hundredths of a second. And the short circuit protection inside the device if the short occurs outside of the device.

@MikeHolt could you do a video explaining when a neutral counts as current carrying? I understand 310.15(E) covers it in perfect detail, however, there are some who believe that the neutral in a two wire 120v balanced circuit would count as current carrying, even though it is excluded entirely from 310.15(E). Some are interpreting the wording of 310.15(E)1) to be a cryptic message that neutrals in a balanced circuit are counted despite no mention of it in the actual section.

Concerning ground rods at detached structures vs. ground rods at generators, as far as lightning high frequency pulses traveling through the ground and up one electrode and through the feeder EGC back to the original building and main service, why is it ok for a detached building and not a generator? Or why if it’s not ok to do that with a generator is it also not ok to do that with a detached building? 18 year electrician and still dont get this.

Does zero sequence pick up on a ungrounded delta during a ground fault condition when using solid state protective relaying?

To make sure I understand. The example of the crossed neutral - there were two mistakes that lead to the electrocution? The first being a crossed neutral and the second tying the transformer equipment ground to the X0 transforme neutral connection creating the objectionable current path. Is this correct?

This all makes sense for rooftop arrays, but what about ground-mount arrays? Seems like it would be far more effective to terminate the grounding conductor for the array into a couple of ground rods right there than to run a separate grounding conductor all the way back to the main panel, especially if the array is located more than 100' away. The stray inductance and resistance of the raceway grounding conductor is going to be a serious obstacle to diverting surge current from an indirect lighting strike, if not outright useless.

Thanks Mike, it’s been many years since I first heard this video and it is such a great video that I am sure that has helped save the lives of others. All, the best, Steve from ElectricalTime

in your illustration at 6:05 timestamp, where # 3AWG is used as the EGC, wouldnt that violate 310.10 (G) (1) where it states you must used 1/0 or larger? or does this not include EGC's?

so.......on both panels, theres a neutral-ground bond?

These are commercials right? Informative marketing. U SOB, I’m in!!

Liberals are the modern fascist they believe they have the right to dictate how you speak and how you should behave

Somebody in the journey band approved this song to be played at Republican rallies and I’m glad he approved the song

I was watching you years ago when you were doing small venues. Your popularity has grown exponentially. Now you have audiences of 3 to 500 people. It's amazing. of course it's well deserved. You're THE goto person to settle a question. Do some barefoot skiing videos. Remember the saying all work and no play. You deserve some play time.

Thank you Mike, you deserve a standing ovation for your service to the Electrical community. Your books are my go-to guides from the start of my career and maybe till my retirement. Full respect!

I’ve built radio towers, they require ground rods at the base of the tower as well as the top (for lightning protection) we always have power ran to the base of the tower….. what do we do in this instance? keep the grounds separate?

Thank you Mr. Holt. I will add E^2 over RP to my P over IE, and E over IR memorized formulas. I think of all the times I have taken the long way around.

Too bad the EI doesn’t follow this page!

I agree with everything. For some reason mocp is at 25 but when I do the math with compressor at 17.5 amps at 225% plus the fan motor at (.78) I get a number much higher then the units 25 amps..

Was there and had a great time! Would highly recommend to any electrician looking to advance themselves and get that extra push! Thanks for all you do for us!

I have a metal pole fed by 3 wires: ground, null and phase 230V). I've already connected the groundc onnection to pole body. Is there any good reason to now add a new grounding rod to the pole? If not, does it do any harm in doing so? (hose grounding will them be connected to this new pole rod..) Thanks.

Does 240v in residentials always require a center tap? I was told center tapping was outdated

Well done. And thank you for being instrumental in passing my master's exam, on the first attempt and with a high score. Could not have done this without you, Mr. Holt. <3

If you ever come to New Mexico I would definitely attend

Thanks. For all the time you pit into the trade

Thanks for sharing your knowledge.

I just finished boot camp.

Thank you for the great explanation of code! Sadly sometimes it’s cheaper to upsize the wire than get on a dinosaur inspectors bad side. 😓 But with the price of copper today it will be good to have this knowledge in my pocket! Are A/C circuits exempt from 80% rule for continuous use circuits?

Here is my concern with all of this. For the moment let us forget about all of the codes and ampacity of the circuit. looking at the nameplate we are seeing the running load, not the start-up current. The voltage drop across the smaller-sized wire at start-up will make it harder on the compressor to start and possibly shorten its life.

Not being able to would be stupid. We're not using super sensitive load cells here. We're running 120v at maybe 20A.

NICE VIDEO Mike, ...make sure your students know effects of 'power factor' (is this in another video?) Some things only work for purely resistive loads....which homes are NOT. THANKS MUCH!!! ps I remember seeing a small 'generator test-truck'. It was loaded with a huge resistor-bank to rate portable generators....big surprise when the generators didn't work to 'proven spec' when running at home!

Youre also probably going to be landing a grounding conductor along with your current carrying conductors in your furnace.

A couple of clarifications concerning Y-type and Delta-type transformers; In Y transformers with a neutral, I-Line=I-Phase and V-Line=Rt.3 x V-Phase. In Delta-type transformers V-Line=V-Phase and I-Line= Rt.3 x I-Phase. It is not all that simple to introduce a neutral in Y-type transformers.

Thankyou for making thing better in the world..

Think about your answer!

Nice one Mike, Thanks 🙏

Sometimes those poles work on 480V .....you really don't want to see how it feels....!!!

You could follow the code, or you could do what the professional installer did at my local Red Cross office, and bond the satellite dish to the natural gas pipe.