When a high voltage current limiting fuse melts, what does it do to the voltage on the system? 1

[bdn2004]

In the IEEE Red Book there is this statement that it does not clarify. Can someone explain?

"When applying a current-limiting fuse of a given voltage rating over 600V on a circuit of a lower voltage rating, consideration should be given to the magnitude and effect of overvoltages that will be induced due to the zero current forcing action of the fuse during the interruption of high-magnitude fault currents."

 

[xnuke]

Tutorial and Guide for HV Fuses, IEEE and IEC Cooperation

xnuke
"Live and act within the limit of your knowledge and keep expanding it to the limit of your life." Ayn Rand, Atlas Shrugged.
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[cuky2000]

The current limiting fuse (CLF)operation is chacracterized by producing an overvoltae at the begining of the melting cycle. The effect of the large arc voltage is to limit the peak current that results, and to reduce the duration of current flow.

The arc is essentially a resistive impedance, and this causes the current to be considerably reduced from the prospective current. The transient recovery voltage effect in CLF has an smal impact.

 

[RRaghunath]

The overvoltage and prevention of restrike is a challenge for the fuse designers. The concern is great especially when an inductive circuit is being interrupted.
I am sure the HV fuse will not cause overvoltage beyond the system rated insulation withstand values.

 

[RRaghunath]

xnuke, Thanks.
The Tutorial document gave a good insight in to the preparation of unified IEC/IEEE document on HV Fuse application guide.