Synchrowave 250 150 amp breaker wire size

[Willie B]

The innards of a circuit breaker have no deliberate current, or voltage limiting devices. They may lose voltage by way of dirty, or damaged contact points.
Please understand that turning off in an overcurrent event is not current limiting. A 100 amp overcurrent protector will trip at 100-800amps. It does not limit that current from going to 800 amps in the first place.
There is wide range of specifications where an overcurrent device will tolerate current for a given time, I've seen none rated as current limiting.
Current limiting devices are available, they are expensive, so application is limited.

[William McCormick]

The innards of a circuit breaker have no deliberate current, or voltage limiting devices. They may lose voltage by way of dirty, or damaged contact points.
Please understand that turning off in an overcurrent event is not current limiting. A 100 amp overcurrent protector will trip at 100-800amps. It does not limit that current from going to 800 amps in the first place.
There is wide range of specifications where an overcurrent device will tolerate current for a given time, I've seen none rated as current limiting.
Current limiting devices are available, they are expensive, so application is limited.

The points are current-limiting devices, and the braided ribbon cable is a current limiting device. When you draw starting amperage for a large motor five horsepower single-phase motor, it tries to draw unlimited amperage infinite amperage for a split second. The points and ribbon limit the amperage drawn.

There is always high heat in a breaker outputting more than 50 percent of its rated output. Much higher than the wire it is feeding, if the wire it is feeding is correctly sized for the breaker's output. That heat is current-limiting at work. With fire pumps, there is too frequently a problem with the motor starter points overheating, to a point it was hurting the industry, because they were not seen as current-limiting devices. With the thermal cameras, they are now proving it to be the points that are causing a voltage drop.

Consider that an induction motor tries to draw infinite current upon start, and there are often three sets of points and three ribbon cables between the infinite current at a transformer, for an instant, and there is certainly going to be a voltage drop. I am not saying the ribbon is too small to carry the amperage marked on the breaker, it might be oversized, but everything is too small upon start. And it is a good thing, or the transformer would supply unlimited amperage and drop to about 1,600 amps before detonating if it is not protected.


It is the voltage drop formula that explains the problem of multiple resistors. Even heavy wire starts to calculate into the formula in a big way. That is why the wire from the transformer to your house feeding a 60 amp panel could carry 1600 amps or more all day long because there is no resistance. That same piece of wire after a breaker can become undersized if it feeds a large piece of induction equipment that draws 150 amps.



After doing a lot of HVAC I found a couple units that toasted large number two wire fedding a seven and a half ton compressor, it was a case of the safties cycling the compressor on and off. Even though the wire was over kill by multiples it still melted and never took out the breakers. It was odd because we noted that the wire was large and yet melted so we figured it was a design flaw that they knew about and just tried to up the wire size incase. It was not enough.


Sincerely,

William McCormick

[William McCormick]

The innards of a circuit breaker have no deliberate current, or voltage limiting devices. They may lose voltage by way of dirty, or damaged contact points.
Please understand that turning off in an overcurrent event is not current limiting. A 100 amp overcurrent protector will trip at 100-800amps. It does not limit that current from going to 800 amps in the first place.
There is wide range of specifications where an overcurrent device will tolerate current for a given time, I've seen none rated as current limiting.
Current limiting devices are available, they are expensive, so application is limited.

There are also bimetallic elements that are designed to open the breaker and cause a magnetic field. So there is plenty of components to limit current. Today the new ARC fault, Ground Fault breakers get hot just being turned on.



Sincerely,

William McCormick

[Willie B]

A breaker will carry many multiples of its rating for a time. A 100 amp breaker will carry 800 amps briefly. It doesn't restrict current, it breaks the circuit. The difference seems small. If it were current limiting it would prevent it ever exceeding 100 amps in the first place.

[William McCormick]

A breaker will carry many multiples of its rating for a time. A 100 amp breaker will carry 800 amps briefly. It doesn't restrict current, it breaks the circuit. The difference seems small. If it were current limiting it would prevent it ever exceeding 100 amps in the first place.

Square D breakers have had the warning 10,000 amp throughput possible right on their face. At 240 volts with a 24-volt drop, to push 800 amps, the resistance would need to be 0.03 ohms through the entire circuit, I have never seen that circuit so perhaps with a surge, a blown transformer, or a lighting-strike that would be easily possible. But no way through multiple points, ribbons, and multiple bimetal devices. You can see the metal warp, in order to heat the element, there needs to be high resistance at only 20 amps. When you up that to starting amps which are infinite, because of the points, ribbons, and bimetal devices, it cannot draw that or anywhere near that with only a 240 volt supply voltage. The voltage drop would be more than the voltage applied. Because of the Voltage drop formula, if the circuit had a resistance of 0.175, in order to get 800 amps there would be a 140-volt drop in the line.

Sincerely,

William McCormick

[danielplace]

What Willie B is saying is UNTIL the points open any amount of current could pass through a breakers contacts. They are NOT current limiting EXCEPT by completely disconnecting the circuit. UNTIL that occurs the breaker is part of the circuit and low resistance just like the wire so for a short time it could deliver much more current than just the rated size. No part in a standard breaker is current limiting in the very short term.

A current limiting breaker is like a 400 amp tig welder set to 100 amps. It limits the current available in real time.

Many devices are called current limiting but not in the sense of what Willie B is considering. Momentarily many can pass more than the rating.

[William McCormick]

What Willie B is saying is UNTIL the points open any amount of current could pass through a breakers contacts. They are NOT current limiting EXCEPT by completely disconnecting the circuit. UNTIL that occurs the breaker is part of the circuit and low resistance just like the wire so for a short time it could deliver much more current than just the rated size. No part in a standard breaker is current limiting in the very short term.

A current limiting breaker is like a 400 amp tig welder set to 100 amps. It limits the current available in real time.

Many devices are called current limiting but not in the sense of what Willie B is considering. Momentarily many can pass more than the rating.

What I am saying is that a very small amount of resistance will stop an 800 amp current from flowing by making the voltage drop greater than the voltage supplied, except for surges, transformer blows, and lightning that raises the voltage enough to allow that.

Contacts do limit current at start amperage. And the bimetal limits current, which causes the ribbon to limit current. It is only on start that they cause a large voltage drop. Or if you put too large a wire or too small a wire after a breaker and start an induction load too often in a certain period of time. That is what happens with HVAC compressors if the safties cause the compressor to cycle too often in a certain time frame. Welders as well, cause the same problem. They draw a very high current for a split second that causes the points and ribbon to heat, do that often enough in five minutes, and the breaker does not just blow; it gets very hot. Fix the low voltage situation, and the welder can run on a 70 amp breaker. If you don't, it will blow a 100 amp breaker. Some guys here by me where the voltage is 240 wire the machine for 208, and it works, I do not do that, but it works.
Fire pumps that are calculated by electrical engineers and are "Overrated" suffer contact failure and even fire. When the Jockey-Pump, a small pump that maintains pressure in the sprinkler system, fails, and the main fire pump cycles too many times in an hour. Since they have the thermal imaging cameras now, they can see the heat created at the contacts, even when the pump is just running normally. It is because contacts limit current and create resistance. Resistance in a circuit times amperage is the voltage drop.

The voltage drop formula does not just add up resistances in the circuit. It multiplies the resistances and then divides them, which causes more resistance than just the addition of resistances. When you oversize or undersize a wire after a breaker, it takes out the breaker by allowing too much inrush current in the case of an oversized wire or causing too much resistance in an undersized wire. That is why branching the breakers in size order is so critical.
When you place an oversized or undersized wire between breakers, that is the greatest sin possible.

Sincerely,

William McCormick

[William McCormick]

What Willie B is saying is UNTIL the points open any amount of current could pass through a breakers contacts. They are NOT current limiting EXCEPT by completely disconnecting the circuit. UNTIL that occurs the breaker is part of the circuit and low resistance just like the wire so for a short time it could deliver much more current than just the rated size. No part in a standard breaker is current limiting in the very short term.

A current limiting breaker is like a 400 amp tig welder set to 100 amps. It limits the current available in real time.

Many devices are called current limiting but not in the sense of what Willie B is considering. Momentarily many can pass more than the rating.

There was a guy that climbed the pole to hook up up his cheaters to power his welder in Brooklyn and blew the transformer and lost his life because he did not include a circuit breaker between the welder and the unlimited momentary current in the transformer. He was an iron man, going to put in some railings. When I told my boss the reason why it happened he was not relived rather he kind of looked down at me for not saying something sooner.

Sincerely,

William McCormick

[danielplace]

There was a guy that climbed the pole to hook up up his cheaters to power his welder in Brooklyn and blew the transformer and lost his life because he did not include a circuit breaker between the welder and the unlimited momentary current in the transformer. He was an iron man, going to put in some railings. When I told my boss the reason why it happened he was not relived rather he kind of looked down at me for not saying something sooner.

Sincerely,

William McCormick

Whatever he did he just screwed up. If there had been a main breaker inline it would have been no different because again the breaker does nothing to control initial inrush. If he screwed up and brought the legs together unfused the explosion would have been significant and at some point a breaker would have possibly helped but it still would be quite a explosion. There should not have even been a spark if the machine was shut off. If it was on it would have had to have been cranked up and the stinger grounded and if he did that and tried to make a slowly made connection it would throw some sparks but should not have killed anyone. He went phase to phase and royally made a fatal mistake is all.


You realize as a licensed electrician the power company will often give you a cheat box specifically designed for connecting directly to end of the drop straight from the transformer. There is no breaker. Some will have a screw in glass fuse in them and also a GFI receptacle. We had half a dozen floating around the service dept so you have power while doing service changes. Yes legally approved theft of electricity.

You would have to be smart enough not to have something plugged into it and drawing a load while you were connecting it the the ends of the drop or you will see sparks and ruin the alligator clips.

[Willie B]

Whatever he did he just screwed up. If there had been a main breaker inline it would have been no different because again the breaker does nothing to control initial inrush. If he screwed up and brought the legs together unfused the explosion would have been significant and at some point a breaker would have possibly helped but it still would be quite a explosion. There should not have even been a spark if the machine was shut off. If it was on it would have had to have been cranked up and the stinger grounded and if he did that and tried to make a slowly made connection it would throw some sparks but should not have killed anyone. He went phase to phase and royally made a fatal mistake is all.


You realize as a licensed electrician the power company will often give you a cheat box specifically designed for connecting directly to end of the drop straight from the transformer. There is no breaker. Some will have a screw in glass fuse in them and also a GFI receptacle. We had half a dozen floating around the service dept so you have power while doing service changes. Yes legally approved theft of electricity.

You would have to be smart enough not to have something plugged into it and drawing a load while you were connecting it the the ends of the drop or you will see sparks and ruin the alligator clips.

Done it a few hundred times homemade. OSHA, the power company, and it is theft of power. No one would approve. I've only done it if Mrs Smith could simply not tolerate interruption of power during a service change out. No explosions, or electrocutions, none of that.

[William McCormick]

Whatever he did he just screwed up. If there had been a main breaker inline it would have been no different because again the breaker does nothing to control initial inrush. If he screwed up and brought the legs together unfused the explosion would have been significant and at some point a breaker would have possibly helped but it still would be quite a explosion. There should not have even been a spark if the machine was shut off. If it was on it would have had to have been cranked up and the stinger grounded and if he did that and tried to make a slowly made connection it would throw some sparks but should not have killed anyone. He went phase to phase and royally made a fatal mistake is all.


You realize as a licensed electrician the power company will often give you a cheat box specifically designed for connecting directly to end of the drop straight from the transformer. There is no breaker. Some will have a screw in glass fuse in them and also a GFI receptacle. We had half a dozen floating around the service dept so you have power while doing service changes. Yes legally approved theft of electricity.

You would have to be smart enough not to have something plugged into it and drawing a load while you were connecting it the the ends of the drop or you will see sparks and ruin the alligator clips.

A fuse or breaker both limit inrush current. Because both are elemental, at that amperage the resistance goes up and the maximum current goes down. If not it will take the pole transformer with it. At 0.3 ohms of resistance, you can no longer get 800 amps from a 240-volt source because the voltage drop will be 240 volts.

A good friend and motor rewinder had to maintain 240 volts at 100 amps to complete the test on a motor he rewound for the NAVY. The amperage and voltage kept falling off during the start, not by much but he was an honest guy and wanted to do it right. So they bypassed the breaker and the power company transformer blew off the pole. When the linemen got there to replace it he explained that the breaker is a current limiting device as well as a circuit breaker and that you can never connect an induction load like that to the transformer without a circuit breaker in between.

Since then have they added in controls or current-limiting devices? I have no idea. However, at those times mentioned that is how it was.

Sincerely,

William McCormick

[William McCormick]

Done it a few hundred times homemade. OSHA, the power company, and it is theft of power. No one would approve. I've only done it if Mrs Smith could simply not tolerate interruption of power during a service change out. No explosions, or electrocutions, none of that.

As long as you put it through a current limiting device you are good, any correctly sized fuse or circuit breaker will do.

A #1 AWG wire 50 feet long will carry 1,600 amps as long as it is direct from a large transformer with no current limiting devices. It will only have a voltage drop of fewer than 9 volts at 90 degrees all day long. After a circuit breaker, it certainly can no longer carry that amperage and it is because of the breakers or fuses, they are current-limiting devices.

Sincerely,

William McCormick

[Willie B]

As long as you put it through a current limiting device you are good, any correctly sized fuse or circuit breaker will do.

A #1 AWG wire 50 feet long will carry 1,600 amps as long as it is direct from a large transformer with no current limiting devices. It will only have a voltage drop of fewer than 9 volts at 90 degrees all day long. After a circuit breaker, it certainly can no longer carry that amperage and it is because of the breakers or fuses, they are current-limiting devices.

Sincerely,

William McCormick

The current limiting device is the computer, light bulb, or vacuum cleaner Mrs. Smith uses. And no I don't always use a circuit breaker.

[danielplace]

Done it a few hundred times homemade. OSHA, the power company, and it is theft of power. No one would approve. I've only done it if Mrs Smith could simply not tolerate interruption of power during a service change out. No explosions, or electrocutions, none of that.

They are approved for use during a service changeout by the power company. The power company gave us the cheat boxes and they show up and see us using them and say nothing because they know it is perfectly OK. They don't use them much if ever so they are buying them basically already knowing they are giving them to us.

It is unmetered use that has been approved.

All the time the power company will have a meter socket burn up and they will jump out the meter base and run power right straight through the meter can and it will stay that way sometimes for 3-4 days before we can get there to change out the meter can. They carry all kinds of premade jumpers that are specifically designed to bypass a meter with no matter which way the meter base burnt up. The have lugs that go to flat blades to plug in singly to the sockets and connect to customer service wire. They do not ever adjust these peoples bill. When the meter base/meter are fixed that is when the meter goes back in and starts again right where it left off.

[William McCormick]

They are approved for use during a service changeout by the power company. The power company gave us the cheat boxes and they show up and see us using them and say nothing because they know it is perfectly OK. They don't use them much if ever so they are buying them basically already knowing they are giving them to us.

It is unmetered use that has been approved.

All the time the power company will have a meter socket burn up and they will jump out the meter base and run power right straight through the meter can and it will stay that way sometimes for 3-4 days before we can get there to change out the meter can. They carry all kinds of premade jumpers that are specifically designed to bypass a meter with no matter which way the meter base burnt up. The have lugs that go to flat blades to plug in singly to the sockets and connect to customer service wire. They do not ever adjust these peoples bill. When the meter base/meter are fixed that is when the meter goes back in and starts again right where it left off.

The meter pans I use have a knife switch to bypass the meter. But the meter is not supposed to be the current limiting device it is the main breaker and subpanel breakers that do that. But because it has points it can limit current. If you saw the movie I posted you can see that heat is created in the bimetal which requires ohms/resistance to do, that is what limits the current. Take that out hook up a large induction device and boom.

Sincerely,

William McCormick

[danielplace]

The meter pans I use have a knife switch to bypass the meter. But the meter is not supposed to be the current limiting device it is the main breaker and subpanel breakers that do that. But because it has points it can limit current. If you saw the movie I posted you can see that heat is created in the bimetal which requires ohms/resistance to do, that is what limits the current. Take that out hook up a large induction device and boom.

Sincerely,

William McCormick

You missed the point entirely. Using power without meter can be perfectly legal when it is power company approved.

When they say you can steal the power then it isn't theft anymore. They do it all the time. I have done some large services before feeding lift stations that can only be down so many hours. The power company knows you are going to be running with can open and bypass left up stealing power when they get there. I have seen them stay that way for a week with no meter in them stealing power legally.