Hubbell lighting hl Videos

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The reclosers I worked with in the 80's had three stages. The recloser is tripped by a solenoid that pushes against a spring and opens the contacts at the same time. The solenoid is sized so an over-current condition will cause it to operate. The first trip results in the spring tension re-closing the contacts almost immediately. It also causes an orifice to move into place, restricting the flow of oil pushed by a piston connected to the reclosing mechanism. If the fault still exists then it trips a second time but the speed of the solenoid is slowed and it doesn't open the contacts for a couple of seconds. If any tap line has a fault the over-current condition will cause the tap line fuse[s] to blow, clearing the fault. The reclosing spring then closes the contacts again. If the fault is cleared, the solenoid doesn't open the contacts and power is restored (except in the faulted tap line). If the fault is not cleared, the solenoid operates a third time with a longer delay due to a smaller orifice moved into place. The contacts are reclosed again, and if the fault still exists the solenoid opens the contacts one final time, and due to a the further movement of the orifice mechanism, trips a link and disables the ability of the spring to re-close the contacts, leaving the line dead past the recloser. The size of the solenoid and the tap line fuses must be coordinated for the clearing scheme to work. The fault current needed to open the recloser must be larger than the current needed to blow tap line fuses.

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how current in earth wire causes fuse to blow?

A few weeks ago they replaced the transformer that we are on right in front of my house, it took them 15-20 minutes. Later on that day when the power was restored I discovered that my computer was barbecued and wouldn't turn on, the motherboard green LED was blinking very dimly. I don't know if it was the result of the power line crews.

Nick, Great video. The power at my business here in Houston Texas goes out TOO OFTEN. What Centerpoint energy thinks is too much differs with me. Everytime our power goes out I go to a pole in which the fuse cutouts are tripped. We call the power company.....they send out a lineman and he will replace the fuse cutouts. They don't know why the faults occur. They say birds, squirrels, trucks hitting poles, wind. How much does it cost to install a recloser? I think the only reason they don't do it is because it costs money and or not enough people complain enough.

Not sure if anyone will ever see this but I'm a bit confused. When I was younger and stupid I was on a store roof that has power lines running across it. I jokingly went over and faked getting shocked by one. Should I be dead? Also there was this thing that looked like a fuse cutout i think and I grabbed that also and it felt like I was grabbing one of those fair ground electric chairs. Please respond if you can. 

+Cube Computer Channel On the "dips" you talked about: I grew up with an electrician in the family. He explained that when the power appears to "cut out" for a second and then come back on, it's a different reason than a cut out fuse. This happens when something (for example a lightning strike) causes a feed line to feed the wrong voltage into a transformer station. An automated system cuts off the feed from the transformer station to prevent damage from the sudden change in input voltage (again, lightning strike as the example). Once the feed returns to normal (lightning strike is over and charge has been dissipated) the safety system reconnects the transformer and it keeps working as before. The problem on the receiving end is that when the safety disconnects the TX's feed you don't get a total loss of electricity in your wall plug. Instead (since only the TX's feed, not the TX's output was disconnected) the transformer will keep supplying a few burst of electricity WITH THE WRONG VOLTAGE as the internal magnetic fields dissipate. You can visualize it as a few smaller waves coming after the big waves have been blocked. These "waves" have the wrong voltage, and this causes some appliances' transformers to deliver the wrong voltage to the appliance, causing a brown out for the electronic circuits. This is one of the reasons sensitive systems often have a UPS (uninterrupted power supply, a type of backup battery that cuts out external power and supplies the correct power in case of a brown out). The above scenario can cause a brown-out which can damage some electronics. Most home computers today are protected but many expensive systems need an external or built in UPS in case the above safety system is triggered. A "brown out" is when the supplied voltage doesn't go from operating voltage down to zero immediately, but rather slowly sinks. In some electronics (especially in expensive experimental electronics) this may damage the semi-conductor parts.