National Electrical Code --- Electricians are Special People

[rockmeupto125]

*The general rule of thumb is that circuit breaker size should be 125% of the ampacity of cable and wire or the circuit which has to be protected by the CB.

 

So if my wire is rated at 65 amps, I should use an 80 amp breaker.

 

*but NEC suggests 80% as a safe current limit as compared to the rated current of CBs.

 

80% of 80 is 64 amps. The next highest industry standard is 70 amps.

 

So I use a 70 amp breaker on my 65 amp rated wire with a calculated load of 52.5 amps. ARRRGGGG.

 

I've used the lights, compressor, and welder on a 30 amp circuit with 10 gauge wire for the last 12 years, and only tripped a breaker once with a ground contact on a receptacle that hadn't been replaced after the flood.

 

The temptation is there to use a smaller wire than I had originally intended for my planned 60 amp service.

 

But it's not that much more $$ to just go ahead make it an 80 amp service. 

[SwampNut]

Anything worth doing is worth over-doing.

 

[Zero Knievel]

3 hours ago, SwampNut said:

Anything worth doing is worth over-doing.

 

That was dad's philosophy.  Of course, it makes sense in that you don't worry about overrunning the capability of your setup if it's set to handle more than you will use.

[XXitanium]

...more power!

 

https://youtu.be/KYsu5ZmL214?si=va_gDzRUIQoROsGF

 

 

 

Edited December 21, 2023 by XXitanium

[SierraKLR]

The issue is that most circuit breakers are labled at their free air rating or handle rating.  The moment you put the in an enclosure or any type NEC requires a 20% defraying due to ambient heat.  Hence the 20% derating

 

Wire is tested and labeled at it’s 90 degree C rating, but NEC requires that it be sized ,for load purposes, at it’s 70 degree C rating 

[XXitanium]

...

Edited December 21, 2023 by XXitanium

[SwampNut]

Hey, what do you guys call those non-contact AC detectors that make a warbling noise?  I used my term for it around East coast people and they looked at me like I'd grown a third arm.

 

[ironmike]

Um, AC voltage detector? At least that's what the label on it's side reads (Craftsman model). I can't remember hearing another term for it.

[SwampNut]

Wiggy.  Although it's the trade name for a very early contact-type meter, I've heard the term many times in reference to the non-contact.  If you google it, you get what you expect and also contact meters.  In any case, I'd never do any high voltage work without one.

 

 

 

 

[XXitanium]

I had jiggler in my head. Some random on the web agreed with me. I had a couple different makes in my time.

 

[SwampNut]

Ask an AI...

 

Answer
In electrician parlance, a "Wiggy" refers to a specific type of voltage tester known as a solenoid voltmeter. It is a durable, simple device with two test leads connected to a solenoid coil inside a plastic casing. The Wiggy has an indicator bar attached to the solenoid that moves to show voltage levels when the device is connected to a circuit. It can test both AC and DC voltages and also indicate the polarity of the current. The Wiggy is known for its durability, ease of use, and the ability to give a general approximation of voltage rather than an exact value. It is particularly useful in fieldwork due to its stability and the distinct sounds it makes—a loud click for DC and a buzzing for AC—when connected to a power source
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A "jiggler," on the other hand, is a term used to describe a secondary voltage tester, also known as a glow light. It is a simpler device compared to the Wiggy and is used for detecting the presence of voltage. The term "wiggle" is also associated with this type of tester and is sometimes used interchangeably with "jiggler"
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Both tools are commonly used by electricians for different purposes: the Wiggy for more robust voltage testing and the jiggler for a quick check of voltage presence.

[XXitanium]

Hmm, I thought the devices came in differing ranges. We did some work at decent sized transmission stations. It's been over 10 years.

[SwampNut]

2 minutes ago, XXitanium said:

Hmm, I thought the devices came in differing ranges. We did some work at decent sized transmission stations. It's been over 10 years.

 

The non-contact detectors?  They do.  Or at least, mine specifies a range.  I just tried mine on 24VAC and it was very unreliable.  You have to hold a certain part of it right on the wire (full contact).

[OMG]

Just use your finger, just a light tingle as long as your thumb is on a ground first.😋

[superhawk996]

I assume there's no danger in running a wire that's bigger than the breaker's rating and that the 125% thing is to allow using all the juice that the wire can give.  Voltage drop is your enemy.  I learned the hard way that when I connect to outlets that are farther from the panel my welder's limit decreases dramatically.

 

If your projected needs are anywhere near the edge of XX size wire, go up one.

[SwampNut]

There's no danger, and I assume it must be legal because many houses have 20a-rated wire and they put in 15a breakers.

 

[rockmeupto125]

The purpose of the breaker (OCPD, over current protection device) is to protect the wire.

 

It may not be necessary, but I plan to upsize the wire as much as I can. It's analogous to putting 16 ply tires on a 2 place motorcycle trailer. You can do it, but it's not needed. Sizing up the wiring will cost another $100. The tires would cost lots more.  And unlike the tires, I'm only going to do this once.

[SwampNut]

The tires would actually have a downside though, in bouncing instead of flexing.

 

[JaBr]

On 12/21/2023 at 3:29 PM, SwampNut said:

Hey, what do you guys call those non-contact AC detectors that make a warbling noise?  I used my term for it around East coast people and they looked at me like I'd grown a third arm.

 

Warbler here in the UK

[xrated]

Although the "Wiggy" has proven to be a very reliable test device over the years, one of them could have gotten me killed back in the 90s.  I was still working in the Steel Mill and every Electrician there carried a Wiggy tester with him.  They had leather pouches for them with belt loops and most of us just put the leather pouch on our tool belts with the tester on one side and our actual tool pouch on the other.

 

While testing a 480V 3 phase circuit one day, to see if the power had been removed (we had turn off a 3 phase disconnect, but it was not properly IDed), I pulled the Wiggy out of the pouch and placed the leads on the lines to check for voltage.  Zero volts being shown.  My working buddy said......I'm going to check them with mine too.  When he did, DAMMIT man.....480V phase to phase on all three lines.  As it turned out, that by storing the Wiggy in the leather pouch over the years, one of the test leads wires had broken inside the insulation and was obviously open.  That of course lead to a false belief that the 480V power was off.  

 

So the reminder here is this.  Whatever device you are using to check voltage, always test if FIRST on a KNOWN live circuit.  Then test whatever you are wanting to check voltage on.  Then test the device AGAIN, on a KNOWN live circuit to verify that your tester did not fail.

 

Oh, and BTW.....the devices being talked about for checking voltage without having to make actual contact with the live circuit........We have always referred to them as "Proximity" testers.  I have a couple of AC, one for DC, and one for testing magnetism.  The magnetism one was pretty handy for checking solenoid valves on hydraulic circuits or basically any electrically operated solenoid type valve.

[IcePrick]

24 minutes ago, xrated said:

So the reminder here is this.  Whatever device you are using to check voltage, always test if FIRST on a KNOWN live circuit.  Then test whatever you are wanting to check voltage on.  Then test the device AGAIN, on a KNOWN live circuit to verify that your tester did not fail.

 

My standard, because I hate getting shocked and would probably hate dying even more, is to test as you recommend AND use two separate known good (tested as you recommend) testing devices.  It really doesn't take that long, particularly if you consider that not making sure a circuit is dead before working on it could take the rest of your life.

[xrated]

10 minutes ago, IcePrick said:

 

My standard, because I hate getting shocked and would probably hate dying even more, is to test as you recommend AND use two separate known good (tested as you recommend) testing devices.  It really doesn't take that long, particularly if you consider that not making sure a circuit is dead before working on it could take the rest of your life.

I know the pain of getting shocked all too well.  I got hit with a single phase of 480V to ground (my little finger on my right hand) one time, very early in my career (circa 1981) as an Electrician.  It was TOTALLY unexpected as my working buddy and I were doing some work on a........get this.....250V DC control board.  So how did 480V appear on a 250VDC control board?  Trust me, that was my question.  It seems that someone, well prior to me being there, had a need to use one of the 250VDC relays on the board for an ON/OFF switch for a 408VAC water control valve.  So, they found a 480V source, ran a lead over to a set of normally open contacts on that relay, and used it for turning the water control valve on and off.  No where on the 250VDC board was there a sign, warning, nothing stating "multiple voltage sources....Danger".  Oh, and the best part, no one updated the schematic drawings of it either, so obviously it did not show up on any prints that we had.  And to top it off, as if it needed more fucktardery than I've already described, The 250VDC relay that had the contacts for the 480VAC valve, was an open relay with zero covering over the actual contacts.  That happened on the midnight shift, and trust me, I was waiting for the boss to arrive in the morning to start his shift and we had a very good "come to Jesus" meeting about what happened that night.  It was corrected by the time I came in for my midnight shift the next night, and the print also was updated.

[SwampNut]

1 hour ago, xrated said:

Although the "Wiggy" has proven to be a very reliable test device over the years, one of them could have gotten me killed back in the 90s. 

 

We use this term differently.  I'd always heard it to refer to the non-contact devices that make noise.  But I realize both are correct.  Anyway, to prevent false negatives I always rub it on my shirt and get a positive first.  I used to do the same with every meter test, though now, I just use my version of the wiggy.

 

 

 

Guess what I made?

 

[SwampNut]

1 hour ago, IcePrick said:

My standard, because I hate getting shocked and would probably hate dying even more

 

I was sitting there with Marty solving the problem of running the EV cord from a generator, and speaking all my plans and test results out loud.  At some point I told him why and of course he told me he absolutely knew why.

 

There was no GFCI involved so I let him help.

 

Also, we NEED do what he does best.  That's a hint on the plug.

 

[xrated]

1 hour ago, SwampNut said:

 

We use this term differently.  I'd always heard it to refer to the non-contact devices that make noise.  But I realize both are correct.  Anyway, to prevent false negatives I always rub it on my shirt and get a positive first.  I used to do the same with every meter test, though now, I just use my version of the wiggy.

 

 

 

Guess what I made?

 

LOL.......that's an easy one......a bonding plug for the generator.  Do you have an EMS system for the trailer........Like a Progressive or some other brand, or is this needed for EV charging?

 

Just to be sure, here is a picture of a "Wiggy" whose brand name is a Wiggington.  It reads AC voltage, DC voltage and also shows polarity on the DC side of things based on the little red piece under the plastic cap.  If your test leads are on correctly (Red to Pos. and Black to Neg), the cap will show RED.  If you reverse the leads or someone has hooked up the DC supply backwards, it will flip to Black, as long as you have the leads connected correctly.  And it obviously is not a No contact voltage tester.......but your already knew that.

 

Edited July 8 by xrated