Switching Arc

33 KV Switching Arc

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People & Blogs

Tags:

• HV
• arc
• switching
• pole
• lineman

[Arkthurius]

anybody knows if there is a specific reason why the last disconnector did not have a big acr like the rest? Less load? Better maintenance? just curious...

[B342345415]

The arc is produced when opening the links on a 70 kilometre line. There is nothing at all connectecd to the line. The arc is capacitance / inductance.

[geeklord09]

HE HE....... it farted!!!

[jtreign9097]

thats the normal way to disconnect its dangerous to get close arching can happen since its live and has a load.

[Eastmunda]

We were taught to open single phase switchgear in A-C-B sequence, not A-B-C as shown in the Video. This lessens the chance of the 2nd Isolator (which draws the biggest arc) arcing across to a live phase causing a phase to phase fault which could take the feeder out, not to mention causing an explosion and damaging the hardware.

[kelljm]

@robertgift

On a wye bank, Each phase of primary goes into its own coil which ultimately leads to ground. This is why there is "ground potential" in wye systems. Delta banks derive power from between the phases..in other words, each of the three coils is hooked to two primary phases.

Magnetizing currents are simply the load created by energizing coils (thus a relatively small arc to break).

[robertgift]

@kelljm Thank you, kelljm. I don't understand "just magnetizing currents in the transformers." Reverse emf from collapse of magnetic field in the third transformer?

I need to see a schematic.  I forgot difference betwee Y and /.\

[kelljm]

@robertgift

I am guessing because of three phase (delta) load. Pull one phase and you have dropped 42% of the available kva, but your load becomes open delta. Pulling the second cutout drops the other 58% of your load. The third phase is just magnetizing currents in your transformers.

[Cjudd001]

the last fuse looked toasted. So it would already open cct so no arc.

[robertgift]

@B342345415 Appears to be a typical three-phase circuit.

Why no arc opening the last switch?

Thank you.

[FadeDown]

@jtreign9097 Thats what she said?

[OnnomonnomonnO]

ahhahaa lool..duck:D

[Arkthurius]

Load, either reactive or capacitive, is related to the arcs that form when you disconect this loads. This is just why you have to turn off the load of a transformer when you are going to move the voltage regulator tap. In the circuit of the video, by the position of the fuses it seems that the cables on the right are the feeders and the left ones go to load, which is likely to be distribution transformers.

[ftynmik]

мне послышалось или он по руски быстро сказал "давай!";)) Тогда откуда такой клас напруги?