fuses in series to increase rated voltage?

[rdrast]

@iant - Not meaning that at all, just that having a voting system, similar to that on any of the StackExchange boards. It helps in flagging correct, or exceptional answers for easy review by people browsing for answers.

 

[iant]

Would be a good idea.
There are many from the past
And present
That could be easier to find then.

 

[shooter]

why not put solar cells in 2 parrallel strings giving a nice 400 volts, far better for converter too.

 

[iant]

I will add.
I replaced many HRC fuses in the past.
Most rated at no higher than 600 V

They fit in the palm of your hand. Even those with a 100 amp rating.

I had kept one blown fuse in my desk. For discussion with apprentices.
It was a 100 amp fuse about 15 inches long.

Rated for 22,000 volts.

 

[Andybr]

I will add.
I replaced many HRC fuses in the past.
Most rated at no higher than 600 V

They fit in the palm of your hand. Even those with a 100 amp rating.

I had kept one blown fuse in my desk. For discussion with apprentices.
It was a 100 amp fuse about 15 inches long.

Rated for 22,000 volts.

I assume that this fuse has a striker pin and that it has fired. The normal setup for these fuses is that there is a small explosive charge to fire a pin out of the end of the fuse case which is used to mechanically trip the associated switchgear. This is worth bearing in mind if you are keeping them in your desk.

 

[iant]

Mate I am qualified to switch HV. So yes
I also said Blown fuse.

A 2000 amp 415v bus melted
The LV protection had not been setup during installation (external contractors)

This caused a 22,000 volt 100 amp fuse to blow
The pin fired and triggered the CFS to trip the 2 KVA transformer
The fault also tripped the main isolator.
(5 other transformers in that system).

 

[rootboy]

This ^

https://www.youtube.com/watch?v=ZjXK8Vhm4Po

Another day at the office...

 

[rootboy]

i want to thank you for your replies and concerns. i am sorry for the silly question (maybe i was too tired and not concentrating). i was trying to understand how ABB use their contactor with three contacts in series. anyway do not worry, we have never and we will not explode any fuse. please check our electrical department website ( http://machinery.phoenixlb.com/power-and-control.html ). thank you again. you make the most professional and active automation site on the net...

No, it wasn't a silly question.

On the face of it, it would seem to look like it would work. But the moment one of your fuses opens, the entire system voltage would be across the blown fuse.

And since it wasn't rated for that voltage to begin with, you run a very real risk of jumping across the blown fuse.

 

[iant]

Spot on rootboy.

The video link to YouTube is not a high voltage flash over.
It is at 480 V. Which is not DC and rated at Low Voltage.
But dig down on the same YouTube link
There are others posted. Worth a look.
Then the idea of not using a correctly rated fuse is answered.

There are no stupid questions.
No stupid replies.

Only stupid mistakes for not asking.

 

[rootboy]

Spot on rootboy.

The video link to YouTube is not a high voltage flash over.
It is at 480 V. Which is not DC and rated at Low Voltage.
But dig down on the same YouTube link
There are others posted. Worth a look.
Then the idea of not using a correctly rated fuse is answered.

There are no stupid questions.
No stupid replies.

Only stupid mistakes for not asking.

Thanks!

And for the record, that wasn't me in the video...

 

[iant]

Not me either.