Thanks for sharing. Having a lot of experience seems imperative when working in the situations you mention. Good point about leaving the "loom covering" in place. The insulation seemed fine in my case so I didn't think it was very necessary.

Well alot of homes use K&T as well as Fuse Pannels ! Then you will find people splice Romex into it to give the elution they did a Rewiring Job ! Also people just replace the 2 prong outlets with 3 prong outlets to give the elution the wiring was up greaded !

@@tww1981 There's a belief out there behind the hear-say that by putting a grounded receptacle into a two-wire system, then it's "grounded". It's another example of people believing what somebody told them and the bigger the LIE grows, the more convincing it is.

@@frankpaya690 There is alot of "lets say -- creative wiring " to be found in homes ! That is something Mike Holmes found out on a episode of his show ! Although being a big name contractor on TV ; Mike Holmes should have known there is more than one way to feed both legs of a 240 volt circuit ! Hay it makes the job more interesting !

@@tww1981 lol sounds hazardous!!

Higher frequency PWM would make everything less or not noticeable though. Difference of a few cents. Just old fashioned thinking. I agree with Ben. We need to upgrade the PWM frequencies on all dimmers! Godspeed!

Um no. They don't all use pwm type of power sources and even if they did, obviously some brands have mastered the art. Leds must be current regulated but do not require pwm or pulsed power sources. They are used in all kinds of equipment including indicator lights and are most definitely NOT pulsed in those applications. Especially when using linear power sources . Pwm allows better efficiency of power usage because you are not wasting it as heat which is what happens when using a resistor of sort to lower the current to the LED. Milwaukee has not mastered it's use and are terrible across the board when it comes to their lighting.

Yeah, I started carrying a small padlock with me when doing work at friends houses to lock the breaker box. I was wiring my friends bedroom back in 2019 and the same breaker controlled the room I was wiring and the outlet in the bathroom on the other side of that wall. His wife(nice lady, but a bit of a ditz at times) thought something tripped the breaker when the outlet her hair dryer was in wouldn't work. She went downstairs and flipped the breaker back on, and I saw a flash... Luckily I was over their bed wiring the ceiling fan motor, because that put me straight on my ass.

@@Poptart133g I have a friend whose father, an electrician, was electrocuted that way. He was working on the wiring of a factory and had turned off the power and someone came along and turned the power back on while he was working on the circuits. NEVER RESTORE POWER UNLESS YOU ARE 100% SURE THAT NOBODY IS WORKING ON THE SYSTEM. ALWAYS CHECK -- YOU MAY SAVE SOMEONE'S LIFE.

I bet that's happened way more than once

The major benefit to leaving the original AC cable in place is that a ground is afforded.

@@steveloux4709 ... true, but there was no user connection within the living area. It was strictly an engineering point within the installed system. Boxes grounded back to the mains panel was about it. I have never quite figured out if they even bothered to install a ground rod outside the home in that era... or if it was all bonded to neutral and returned to the transformer.

@@steveloux4709 But the further away from the source you got, the less effective the ground. Plus if the connectors weren't tightened properly, it becomes ineffective.

@@TheTurpin1234 sounds like you have done your own research? The ground of an AC cable is merely needed to provide an effective ground fault current path. I think casting doubt on its effectiveness due to the possibility of improper installation (loose/improperly installed fittings) could be applied to anything in electrical construction that might inhibit the establishment of an effective ground fault current path. Are there more reliable means to ensure an effective grounding program? I suppose that is why the Code recognizes certain installations require redundant ground fault paths, e.g. patient care areas. But if we confine ourselves to properly installed, code-compliant wiring methods, we can be confident in the safety of such installations.

@@rupe53 whether a grounding electrode exists or not, the benefit of the AC cable being bonded all the way to the main panel and to the neutral provides the most critical part of the grounding feature; that is the ability to fault large amounts of current to very quickly open the overcurrent device in a short circuit condition. The ground rod where present is primarily in place to dissipate the energy caused by a lightning strike and little more.

I can tell you this much :: just because you have a newer home ,that does not mean it is wired right ! And watch out on buying any house ! Get a therough inspection done !

This... Is not accurate. Maybe a super cheap house wouldn't have switches, but here in the Midwest every K&T house ive seen has switches for the light fixtures in each room. Most of the time the neutral is switched for some reason, I know that was still legal until I believe about 1930.

Excellent info! thx!

I will preface this by saying I wouldn't recommend this to anyone, but what I do when replacing fixtures on a ceiling that have had a history of being overlamped, I typically find the K&T wiring's insulation disintegrating in my hands. Usually the wire is #14 solid. I take a piece of scrap THHN wire and strip the insulation off a continuous length long enough to sleeve onto the existing wire where the insulation fell apart, then use a much smaller amount of 3M 33+ or 35 to tape where the old insulation meets the new insulation. Obviously if you get the opportunity, it would be better to re-feed the wiring with NM-B cable, but to make that legal, you really almost have to start over, rather than simply run the NM-B back to the next nearest K&T source, which technically is also a Code violation of greater issue.

Well of course your house at the most when it was built had a 60 amp service. My thoughts are if you have knob and tube abandon it yes it will be a chore but you will sleep better at night. Think about this I am certain you have seen old movies with those odd looking round light switches on the walls, well the wiring for those were most probably retrofitted in this buildings and the cuts to install them were plastered over. After a while you will get proficient at it.

I have ran into that old old wiring that replaced the knob and tube stuff and the cord wrap inside a box usually frays and if the wire is manipulated the least bit the black rubber just falls off the wires another thing you will find is copper coated steel wire from world war two. Found out about that when we did some junking in the early sixties and mixed a bunch of it in with good copper and burned the insulation off it to take to the scrap yard. Did not get squat for that load for sure.

We have so many Zinsco service calls, the bus bar always seems to burn out and breakers not tripping so they burn. I really do not like this knob and tube stuff. Eventually I'll change to commercial only.

@@billhale9740 interesting, I'm only 22 so I like learning these things.

Thank you SO MUCH for this post. I have been searching for this information for almost a week. I have been back and forth from repairing or replacing the K&T in my 1900 home after I f**ked up and shorted the H&N. Even an electrician told me to cap it off and run a new line, but the entire 1st floor is on that one breaker. I had already run new 12/2 to the kitchen and bathroom, so I knew enough to be dangerous. The only issue I have is I am not sure where to fish all the runs to get them to the breaker box. The current breaker box is on the back porch and the K&T is coming from the basement. Do move the 100 amp breaker to the basement and/or run the wires from the attic through the space between rooms down to the basement and then back to the breaker box? Any help would be greatly appreciated 👏!

@@TheLowDownDog if the panel is on an outside house wall, run your cable into the basement and fish the cable up inside the wall behind the panel. If your plumbing vent pipe runs straight up from the basement. Drop a snake along the vent/drain pipe down to the basement and pull your circuit up. Leave a pull string along the pipe and you will not have to snake to the basement again. The gable end walls in your attic might be open to the basement. My house is 1920. Your house might be balloon construction, meaning there is no header plate to attach the floor of the 2nd floor, and block the path down the bay. The plate was called a ribbon back then. The last resort, if you cannot make an internal vertical pull, run the circuit up the outside of the building to the attic, sleeve your plastic case cable inside pvc conduit and install sil plates to protect the cable at entry points, top and bottom. If you use metallic conduit, bonding codes apply. I hope this helps you.

If you can, I'd suggest moving all receptacles off the knob and tube. That way you don't need to worry about heavy loads. I'm on my second house rewire with knob and tube. I found similar mixing of newer wire spliced onto the knob and tube. In both cases the landlord said the house used to be knob and tube but was rewired. Not even close - they put newer wire where it was visible and left a lot of k&t. In the first house, I really think they had one circuit for all lights and outlets. Breaker labeling gets creative too. A breaker labeled Living Room was really the living room, the kitchen light and an outlet, an outlet in the laundry area, outside lights, and ungrounded outdoor outlet in a non-weather poof box (!), the light at the top of the stairs, the lights in the middle and back bedroom, the light and both outlets in the front bedroom. The house I'm working on now had the entire second floor plus lights on the first floor, and first floor bathroom lights and the flood light out back all on a breaker labeled First Floor. Lol. Watch out for lights fed from both floors. I thought I had everything off the first floor knob and tube, so I cut the wires that ran through the first floor ceiling. The light at the top of the stairs stopped working. The neutral was taken from the second floor, but the hot came from the first floor. I got that corrected, but there was a wall light in the back bedroom (the only light in that room) that fed up from the first floor knob and tube. One trick that helped me was to use my clamp on ammeter to see what was on the knob and tube going toward the kitchen. I turned on or plugged in various things and watched the ammeter. I could tell that the ceiling light, one kitchen outlet, the light at the back door, one laundry room outlet and light, and the outdoor outlet were all on that pair of knob and tube wires going from the dining room ceiling into the kitchen ceiling.

A tone probe ncvt is a useful tool, if you know it's limitations. I would highly recommend a tester or multimeter as well, if you're going to be doing anything with potentially energized wire (huge amount of information to be gained by metering things anyhow). Klein also makes a device that plugs into receptacles and lighting fixtures and tells you which circuit you're tapped into, at the breaker panel. It's like 30 bucks and may be useful for you.

Makes sense. Obviously KZfaqrs aren't their target market but I know there are ways that they can vary the output without flicker.

PWM is is incredibly more efficient than a series resistor, which wouldn’t flicker but would consume more power. I have an LED flashlight with a low and high brightness setting. I was working on an old 16mm film projector with an exciter lamp and photocell for an optic soundtrack. When I pointed the flashlight beam at the photocell the audio amp played the flashlight’s PWM frequency through the loudspeaker as a loud buzz. I couldn’t see the flashlight flickering but I could hear it, and it only buzzed on low, high was clean.

@@tadonplane8265 That's super interesting. If the PMW is truly that much more efficient I guess I can understand why Milwaukee would use that method. Just a bummer for those that like recording stuff.

@@BenjaminSahlstrom ... not an engineer, but my first thought was they could add a capacitor to the circuit and that would help smooth out the pulses.

Odd that it flickers even on the highest setting though. You'd think it would be 100% duty cycle.

In the basement of a bar, I watched two people disconnecting the electrical wiring from the oil furnace. They had turned off the circuit breaker identified as "furnace". One of them dismantles the wiring, without any particular precaution, and without problems. Then while he has the cable in his hand he pushes it away. The cable touches the metal furnace. Fireworks!

@Nelson Swanberg That was after the residents suffocated from kerosene heaters in the living room with the windows closed.

Abandoned wiring shall be removed that is accessible NEC 725.25 and 800.25 and so much more I could share with you most of all understand the difference between being or not being qualified to perform any type kind of work and be able to do it safely.

Thanks for those additional tips.

love it, THANKS

Also known as farmer's 3 way, or barnyard 3 way, many older farmhouses with outbuildings and a yardlight in between used this setup because you could have a 3 way switch in the house and outbuilding controlling the yardlight, and the outbuilding can have some receptacles constant hot, using 3 wires instead of 4 (not counting the ground. )

Why wouldn't you just change out the box to a deep? Just curious I'm still learning, that's usually what we do.

@@Bludcharg4214 That is an option , but using a dual function breaker can save labor depending , for instance if old boxes set in tile , or all the boxes in the house are old style . Good way to protect a Two wire circuit with out unduly disturbing old K&T wire which should be handled as gingerly as possible if it is going be to be used .

Sometimes there was no insulation whatsoever. In the oldest iteration, one side of the house was neutral and one side was hot. They would just pull a single wire over to the light fixture. The leads would enter on opposite sides of the fixture so no contact ever outside of the switch or lamp base. Of course, back then they one light, one switch and one receptacle. In my own house, they had the receptacle on the wall below the switch --- ABOVE the live gas jet for the space heater. Mm mm mmm.

@@ricoludovici2825 I am 83 now so I can remember when the only receptacle was an add on to the single wire pair with a light bulb attached and a pull chain switch. Darwins law was in full effect.

@@poorfesor I saw a lot of bad KnT splicing with 1st generation electricians tape. You know the stuff: tar impregnated sticky cloth. I still don't understand why they called it electricians tape. It was fire-starter's tape.

@@ricoludovici2825 Yep and every household had a roll or two of it.

@@poorfesor Yup. In the kitchen junk drawer. Along with loose matches and Duco cement.

Those very early houses often had conduit exposed on the finished side of the wall and would go to a round switch with a twistable knob that you would turn clockwise to turn on and clockwise again to open.

It's something that I've definitely started watching out for. I feel like companies could stand to gain a lot by advertising lights that are "flicker free" although I'm not sure how many people actually care about that.

@@BenjaminSahlstrom You know how some people don't even notice that it is the buzz from a bad fluorescent tube that is driven them nuts? Same thing.

Home built in 1959 with knob and tube??? are you sure the home was actually built in '59. That is very late for knob and tube. I've been in homes from the '30s that had the original cloth wire romex, all the knob and tube I'm aware of wad installed before WWII and never seen any installed after about the mid 40s at the latest.

@@Sparky-ww5re 1962 home with K&T here (San Francisco).

@@markcrimmins1879 very cool. Seems they used K&T much later in certain areas of the country. In 1962 grounded romex had been around for a couple of years even before grounded receptacles were required, they would often wrap the ground wire , which was usually 16 gauge with 14 or 12 gauge hot and neutral during this period, around the clamp securing the cable to the box, you'd then have what is known as grounded two prong receptacles, this is where using the coverplate screw on the green tab of a 2 to 3 wire cheater plug will actually provide a ground, of course nobody used it like that.

You do run across inspectors that have never actually worked in the tools and as a result don't understand how systems work in any structural sense so they're trying to memorize code rules, rather than going by a working comprehension personally of how something operates.

Sad thing is that if you do not remove it, someone in the future might try to recommission the K&T. I rip it out with a vengeance.

Interesting! Note taken.

I've never seen the insulation, stripped- off when it's between the knob (post).

The problem is K&T wiring is useualy spliced into all over the place ! So finding the source feed is a bit of a job ! Then again newer homes are not always wired right eather ; ( that is something Mike Holmes found out the hard way -- he should have know that there are severl ways to feed both sides of a 220 circuit ) ! Remember this working on 220 circuits always test both legs of the circuit to make shure all power is off !!

Totally agree! The camera angle didn't show it very well but the wires were pulled into separate openings.

I don't think they're going to be used anymore that's why he is running a Romex. Having said that, they are de-energized.

@@BenjaminSahlstrom - Ahhh, my apologies ! Well done then :-)

Should have kept the loom on the wire extending the loom into the box.

If you have an old panel and you are looking to upgrade, I would put a new panel in. Anticipate that you or someone else may want to rewire in the future, so put a larger panel in to handle potential growth in electrical use. It sounds like it would be a large undertaking, but I would get rid of the K&T.

Same rule apply for bx?

That video should be out in the next week or two!

Yes, yes yes and yes! Totally agree

That is super interesting. Makes sense I suppose.

I do know that is a workaround that works but it just adds another complexity to the recording process that I would like to avoid if possible. :)