Standards Development

Scope

This standard is applicable to fuses incorporating enclosed current-limiting fuse-links with rated breaking capacities of not less than 6 kA, intended for protecting DC circuits of nominal voltages higher than 1500 V DC. The object of this standard is to establish the characteristics of fuse – links. For this purpose, this standard refers in particular to

– the following characteristics of fuses:

 rated values.

 temperature rise in normal service.

 power dissipation and acceptable power dissipation

 time/current characteristics

 breaking capacity

 cut-off current characteristics and their I2t characteristics

 arc voltage characteristics

– type test for verification of the characteristics of fuses

– the marking of fuses

Requirements apply to fuse-links for application with time constants below 3 ms in equipment containing circuits of nominal voltages above 1 500V. Fuse-Iinks in this standard can also be referred to as

• semiconductor fuse-links (aR, gR, gS)

• Photovoltaic fuse-links (gPV)

• Battery fuse-links (aBat, gBat)

In most cases, a part of the associated equipment serves the purpose of a fuse-base. Owing to the great variety of equipment, no general rules can be given; the suitability of the associated equipment to serve as a fuse-base should be subject to agreement between the manufacturer and the user.

Purpose

There is an increasing market trend for DC applications (e.g. battery systems, use of machinery and converters with AC/DC and DC/DC, PV-systems, etc.)

The technology trend is the development of low-voltage fuse technology to the range of high voltage up to 15 kV DC.

From the voltage side it would be a high voltage fuse, from the technology side it would be a low voltage fuse.

Since this is a case of overlapping of the scopes of SC32A and SC32B, it was decided by the TC 32 to develop this standard as a TC32 project and jointly develop a standard.