AC inductive effect

Teken

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tangent

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Back in the early 70's when testing traffic signal cabinets before installing in the field, we'd burn-in the controllers (with microprocessors or micro-controllers, etc.) for 30 days, inspect the workmanship, adherence to specs, etc.

A very unsophisticated but effective way to put EMF spikes on the AC power line feeding the cabinet was to energize/de-energize just plain, old fashioned 120VAC relay coils from that same AC line. The back-EMF placed on the line by the collapsing field when the coils de-energized could actually cause an improperly filtered and suppressed signal controller to go from a green traffic signal display in the field directly to red with no yellow display for 3 to 4 seconds in between or shorten that yellow display to 1 second...not good!
Inductors resist changes in current flow and capacitors resist changes in voltage. Force either to do so rapidly and they scream (emit EMI).
So says ELI the ICE man (E=Ldi/di; I=Cdi/dt where E = V because physicists)
 
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TonyR

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Inductors resist changes in current flow and capacitors resist changes in voltage. Force either to do so and they scream (emit EMI).
So says ELI the ICE man (E=Ldi/di; I=Cdi/dt where E = V because physicists)
This is what we used and it worked well and consistently==>> Quencharc® Arc Suppressor/Snubber Network
Radial metallized polyester RC network for transient suppression from Cornell Dubilier


Quencharc capacitors combine a resistor and a metalized polyester film capacitor together for transient suppression. These networks are made to suppress noise and arcs, protect relay contacts, and provide noise reduction on controllers and drives. The Quencharc series is available in a .50 µF, 1.00 µF, and .10 µF capacitance level and come in various ½ W resistance values.
 

Teken

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More info ==>> Quencharc® Arc Suppressor/Snubber Network
Radial metallized polyester RC network for transient suppression from Cornell Dubilier


Quencharc capacitors combine a resistor and a metalized polyester film capacitor together for transient suppression. These networks are made to suppress noise and arcs, protect relay contacts, and provide noise reduction on controllers and drives. The Quencharc series is available in a .50 µF, 1.00 µF, and .10 µF capacitance level and come in various ½ W resistance values.
Been using a few snubbers for home automation for many years. More specifically for ceiling fans that seemed to be blowing up the fan controller. :facepalm: Had to find the correct (capacitive) value for the snubber so as not to absorb the powerline signal.
 

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Been using a few snubbers for home automation for many years. More specifically for ceiling fans that seemed to be blowing up the fan controller. :facepalm: Had to find the correct (capacitive) value for the snubber so as not to absorb the powerline signal.
I'd be curious your experience with home automation fan controllers. I've got a ceiling fan I'm considering automating.
 

Teken

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I'd be curious your experience with home automation fan controllers. I've got a ceiling fan I'm considering automating.
In this instance the brand and protocol Insteon was shut down. Than, later bought by a few customers that indicate they plan to relaunch the Insteon hardware line. As of this writing there is zero stock in any of the Insteon hardware so you'll be hard pressed to buy one new.

Regardless, the Insteon FanLink had a production year where the unit would fail due to the ceiling fans kick back from the CEMF. I never personally experienced this fault so it could be a bad production year vs issues related to a specific fan model.

My experience has been great with the Insteon FanLink as it allows me to circulate the cool / hot air throughout the home without human intervention. :thumb:

Every part of the home is embedded with more than 86 (1-Wire temperature & humidity) sensors which go to several controllers. They take all the real world environmental's and react to the homes condition. The system is programmed and staged from passive to active measures to keep the home warm / cool.
 

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Been using a few snubbers for home automation for many years. More specifically for ceiling fans that seemed to be blowing up the fan controller. :facepalm: Had to find the correct (capacitive) value for the snubber so as not to absorb the powerline signal.
We also used them to increase the load encountered by triac outputs so they'd have no off-state leakage when driving low current devices (it takes some gate current to turn off the triac completely).
 

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^ 100% Illegal and unsafe and will damage / kill someone down the line.
The house was made in the 1800s. There isn't a single thing there up to any modern code.

Worst that will happen is the network signal will be degraded too much. The Romex is direct burial, so it has extra insulation.

Here's the electric service in the house I grew up in. Those rocks, the foundation.
IMG_5029.JPG

11827A61-3EE0-492D-B4EF-E0D8390FCA6F.JPG
 
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Teken

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The house was made in the 1800s. There isn't a single thing there up to any modern code.

Worst that will happen is the network signal will be degraded too much. The Romex is direct burial, so it has extra insulation.

Here's the electric service in the house I grew up in. Those rocks, the foundation.
View attachment 132729

View attachment 132730
The reality is the 100’ Ethernet cable you ran is going to be a real nice antenna. Should your area see lightning be prepared to lose some equipment.

In the worst case scenario shielded Ethernet cable would have protected you from both the 120 VAC line and induced lightning if properly bonded to the homes single point earth grounding system.

It would be very sad to learn you lost equipment or someone was harmed due to the above.

Just some things to consider . . .
 

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The house was made in the 1800s. There isn't a single thing there up to any modern code.

Worst that will happen is the network signal will be degraded too much. The Romex is direct burial, so it has extra insulation.

Here's the electric service in the house I grew up in. Those rocks, the foundation.
View attachment 132729

View attachment 132730
Wow...I haven't seen Type S (rejection) fuses in a while, much less the glass type T (non-rejection) glass fuses. Few people under the age of 50 have unless they're looking at a house of your vintage. I guess at some point before the Romex and UF there was knob and tube in there?

My wife's old house where my MIL lives now was built in 1911 but was re-wired by her dad in the 50's with Romex and breakers but OMG, you should see some of his work.....for instance, more than a couple of breakers have more than just 1 wire on the load side. There's a 40 Amp 2-pole for an electric water heater with 2 #8's feeding the WH but also screwed under the load size on one pole of the breaker is a #14 that feeds a dishwasher, so a #14 is protected with a 40A breaker, not a 15A as it should be. No wonder we see plenty of houses burned down by electrical issues.

Some folks should NOT be DIY when it comes to electrical wiring. :headbang:
 

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The house was made in the 1800s. There isn't a single thing there up to any modern code.

Worst that will happen is the network signal will be degraded too much. The Romex is direct burial, so it has extra insulation.

Here's the electric service in the house I grew up in. Those rocks, the foundation.
It's fine until it isn't.

Electrical faults can develop slowly over time as oxides form and often wait to rear their heads until something changes like you get a space heater or plug it in to a different outlet. Same with the siding, it's fine until you decide tear it off and inhale the dust.

As for the foundation, it's fine as long as you aren't getting too much water and thus mold in the basement / crawlspace. I've spent way too much time packing hydraulic cement into a foundation like that.
 

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It's fine until it isn't.

Electrical faults can develop slowly over time as oxides form and often wait to rear their heads until something changes like you get a space heater or plug it in to a different outlet. Same with the siding, it's fine until you decide tear it off and inhale the dust.

As for the foundation, it's fine as long as you aren't getting too much water and thus mold in the basement / crawlspace. I've spent way too much time packing hydraulic cement into a foundation like that.
Sure, any of an infinite number of things could cause a serious problem.

Fact is, I'm going to die like everyone else here, from heart disease or cancer.

If I had infinite resources, I'd do everything infinitely better.

That's not an argument to change the electrical code to allow the various violations I've committed or recommendation for others to do so, only saying I'm not following that code.
 

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I'm personally of the opinion that the NEC (National Electrical Code) is a scam. I'm not saying it is wrong or that safety standards are bad. But they seem to be financially motivated and although they do claim to offer free access to the NEC via their website, they put so much friction in the way as to deter anyone who would casually like to get a copy of the rule book for reference. Older versions, you can find a PDF fairly easily. But nobody's got time for old editions when the rule book is constantly being extended and the latest version is much less accessible.
 

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Electrical faults can develop slowly over time as oxides form and often wait to rear their heads until something changes like you get a space heater or plug it in to a different outlet.
Along those lines, Dec. 2019 my stepmom up the road called me, said her small heater in the bedroom went out and she could smell something.

Below is a picture of what happens when you daisy-chain outlet to outlet and use the push-in wire holes in the back instead of forming a loop in your wiring and using the side screws. Those back push-in holes have like a knife-blade to grab the conductor in a small area when compared to a good loop on the side screws. The voltage drop from that poor connection when using a 1500 watt radiant heater caused enough heat to burn the insulation as the heat conducted down the wire. This has been heating up for some time, as the copper has turned orange in color, an indicator it has lost its annealing and ductility, making it brittle. Further evidence is the ivory thermoplastic has turned brown.

I had to move so far down the hot and neutral conductors to cut out the brittle part I had to make a short pigtail, wire-nut and tape and come up to a new receptacle, which I then connected with the clamp and side screws. I also went downstream to the other 2 receptacles, replaced them with new and wired to utilize the side clamps and screws.

claudia-burnt_NEMA5-15R_121319_med.jpg
 
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Teken

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Along those lines, Dec. 2019 my stepmom up the road called me, said her small heater in the bedroom went out and she could smell something.

Below is a picture of what happens when you daisy-chain outlet to outlet and use the push-in wire holes in the back instead of forming a loop in your wiring and using the side screws. Those back push-in holes have like knife-blade to grab the conductor in a small area when compared to a good loop on the side screws. The voltage drop from that poor connection when using a 1500 watt radiant heater caused enough heat to burn the insulation as the heat conducted down the wire. This has been heating up for some time, as the copper has turned orange in color, an indicator it has lost its annealing and ductility, making it brittle. Further evidence is the ivory thermoplastic has turned brown.

I had to move so far down the hot and neutral conductors to cut out the brittle part I had to make a short pigtail, wire-nut and tape and come up to a new receptacle, which I then connected with loops and side screws. I also went upstream to the other 2 receptacles, replaced them with new and wired to utilize the side screws.

View attachment 132834
Definitely a serious issue with the older back stabbing outlets. The newer style uses an internal clamp within the body of outlet. Sadly, because of the same experience from others like you not very many people use this new and improved feature.

Which has been in place for more than a decade . . .
 

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Definitely a serious issue with the older back stabbing outlets. The newer style uses an internal clamp within the body of outlet. Sadly, because of the same experience from others like you not very many people use this new and improved feature.

Which has been in place for more than a decade . . .
Yes, I built this house in '06 so they were side-wired, I've used several newer with the side-clamps since, they do work very well, no bending of loops, etc.
 
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