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Fused cutout

Fused cutout

Fused cutout

(OP)
Can a fused cutout be used to protect low voltage circuits between 120 and 600 volts? Will I still have the same time current curves and AIC?

RE: Fused cutout

Are the fuse links listed for use at those voltages?

RE: Fused cutout

(OP)
No idea, but they say up to 15kv.

RE: Fused cutout

Check with a fuse supplier. For MV current-limiting fuses, the answer is definitely no, they have to be applied within a specific voltage range. For expulsion fuses like fuse links in cutouts, I suspect it may be OK, but I wouldn't take my word on it. Never seen it done.

RE: Fused cutout

(OP)
These are expulsion fuses nothing special.


Out of curiosity, why wouldn't a current limiting fuse work?

RE: Fused cutout

It might work most of the time but a CLF needs a certain amount of available energy to fulfill its current-limiting (arc-quenching) capability. So the published interrupting rating only applies within the specified application voltage range.

I'm really struggling to understand what you are trying to accomplish. Low voltage fuses are pretty cheap. But whatever floats your boat.

RE: Fused cutout

(OP)
This is an overhead line and taps are being protected with standard fused cutouts. I cant think of any other low cost options.

RE: Fused cutout

(OP)
Unless something exists for this application? pipesmile

RE: Fused cutout

What voltage are the taps?

RE: Fused cutout

(OP)
120, 240 and 277.

RE: Fused cutout

A weather proof fused disconnect would seem much more appropriate.

RE: Fused cutout

(OP)
But that would involve a weather head, conduit, and extra cabling. Not to mention anyone at ground level could access it.

RE: Fused cutout

In the UK - which has a generally damp climate - our LV O/H service drops are usually protected by a fused cut-out, essentially a ruggedised and weather-proof fuseholder. We don't have a large problem with people at ground level interfering with them. They're too busy stealing the earthing grids... smile

RE: Fused cutout

(OP)
An enclosed fused cutout? How many amps on average? A rugged weather proof fuse holder with hot stick switching abilities would do the job.

RE: Fused cutout

As Scotty says, these outdoor pole mounted low voltage fuses are in widespread use in the UK. Pretty much every pole mounted transformer substation has them, but they are also used as switchable open points on the distribution system. You can get heads to fit standard hot sticks to operate them, but it is fiddly from ground level. Taking them out is easy, putting them back in is sometimes a pain if they are mounted anything more than about 3or 4m up. The fuseholder is rated for 400A max.

http://www.lucyelectric.com/en/products/low-voltag...

Regards
Marmite

RE: Fused cutout

(OP)
@Marmite: That's exactly what I need, and trying to accomplish. The only hold back being those are difficult to obtain in the US. Only off the shelf solution is a HV cutout.

Out of curiosity, what is the theory behind fusing overhead LV in the UK?

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