Ultimate guide for Fuses types and Current ratings

FUSES, TYPES AND CURRENT RATING

The maximum current that a fuse can carry, without being burnt, is called the rating of the fuses. It is expressed in Amperes.

 Cartridge Fuses

What are the Fuses and Types commonly available in the market as below mentioned its uses, current rating, and benefits.

RATING OF FUSE

The current rating of the fuse for the selected circuit should be equal to the maximum current rating (Full Load Amps = FLA) machinery, appliances or the component connected in the circuit.

REWIRABLE FUSE

Its name as indicating itself, the fuse unit in which only the fuse wire is replaced by a new one, Whenever the fuse is burnout. The entire fuse is not scraped as in the case of other fuses. So this type fuses called Rewireable fuse, it’s comes variable Amps rating, 16A, 32A ........


FUSE WIRE MADE UP AND MAXIMUM CURRENT,

1. Lead and Tin alloy for low current (up to 15A)    Composition: Lead = 37% Tin = 63%

2. Copper and Tin alloy for high current (15A to 60A)3. Tinned Copper: for currents above 60A and up to 100A.


CARTRIDGE FUSES

This fuse unit is in the form of a cartridge (bullet)

It is normally manufactured in the range of 2A to 100A. 

Whenever the fuse burnout, the fuse is replaced by a new one. 

It cannot be rewired, it comes metal cap sealed model. 

Cartridge fuses are used to protect motors and branch circuits.


They are available in a wide variety of sizes, amps and voltage ratings up to 600 amps and 600 Vac.

Cartridge fuses are getting in 2 types


Cartridge fuses will use home, industrial panels as well as air condition, pumps, appliances and other equipment.

1. General purpose fuses have no time-delay and protect appliances other equipment.


2. Heavy duty fuses have time-delay feature.

CONSTRUCTION OF CARTRIDGE FUSE WIRE

•  It is made of either round or flat strip.

•  Fuse wire is made silver and silver alloy for low current (up to 15A)

•  Copper and copper alloy for high current (up to 100A)

•  The cartridge is a glass or ceramic tube with metal caps fixed at both ends, for fuse contacts.it is the field with quartz sand or an inert gas to quench the arc.

HRC FUSES

HRC Fuse

HRC FUSE: High Rupture Capacity fuse unit, it is normally designed for high currents (up to 1250A). Whenever the fuse burnout, the fuse is replaced by a new one.


CONSTRUCTION OF HRC FUSE


Fuse wire: Either round or flat strip, made of copper alloy or lead and tin alloy.

· Silver and silver alloy for low current

· Copper and copper alloy for high current.

ADVANTAGE OF HRC FUSE

1. They require no maintenance.

2. They are reliable.

3. They have consistent performance.

4. They operate at high speed.


5. They clear both low and high fault current with equal efficiency.

I think you understand, what I explained the Fuse and current ratings? Thank you.