Fuse Connection Diagram and Wiring Procedure
A fuse is a protective device used for the protection of overload faults even short circuit faults also. Basically, a fuse has a thin wire or conductor having a very low resistance and high melting point. In normal conditions, when the current flows through it within its limit or below its rating, nothing happens anything but when the flow of current exceeds its limit or current rating it becomes hot. After some time it melted and disconnected the power supply. In this article, we are going to see the connection of fuse in both single-phase circuits and three-phase circuits.
There are so many electrical protective devices available. Fuse is the most common, basic, and old-fashioned protective device. In older days fuses are mostly used in electrical power circuits, load circuits, etc. Nowadays, fuses are used in some electrical and electronic devices or appliances only. The main advantages of using a fuse are - it is low cost, easy to connect, etc.
Fuse Connection and Wiring in Single-Phase Circuit
Our domestic house wiring circuit, single-phase appliances, devices, and lighting circuits are examples of single-phase circuits where the fuses are used. You may see in your house a single or two fuses are used with the main switch. Generally, in most of the cases, a single-piece switch is used.
The main important factor when connecting a fuse is, where to connect. Remember that, if you use only a single-piece fuse in your single-phase circuit, then you must connect it with the Phase, not to the neutral. When you connect a fuse between the main single-phase power source and a load circuit then connect the neutral of the load circuit directly to the neutral of the power source. Connect the phase terminal of the power source to any one terminal of the fuse. Connect another terminal of the fuse to the phase terminal of the load circuit.
In some single-phase circuits, a fuse is needed to connect with both phase and neutral for the demand. In that case, connect the phase terminal of the power supply with any terminal of the fuse. The rest terminal of the fuse connects with the phase terminal of the load circuit. Now, connect the neutral terminal of the power source with any one terminal of another fuse. The rest terminal of the fuse connects to the neutral terminal of the load circuit. Remember that, in case of a short circuit fault, using of double fuse with phase and neutral does provide more safety. When a short circuit fault happens high current flows through both fuses. Here any one of the two gets burned. But when a leakage fault occurs, the excessive current flows through the live fuse only.
Fuse Connection and Wiring in Three-Phase Circuit
A three-phase system may be a three-wire system or a four-wire system. In a three-wire system, there are three phases only - R, Y, and B. There is no neutral.
In a four-wire system, there are three phases and a neutral.
The three-phase system operates at 440V AC supply. So here the voltage rating of the fuse is also a very important factor. Here in the above diagram, the fuses are connected with three phases. The 'R' phase of the power source is connected to the lower terminal of the Fuse 1 and the 'R' phase of the load circuit is connected to the upper terminal of the fuse 1. The 'Y' phase of the power source is connected to the lower terminal of the Fuse 2 and the 'R' phase of the load circuit is connected to the upper terminal of the fuse 2. Similarly, The 'B' phase of the power source is connected to the lower terminal of the Fuse 3 and the 'B' phase of the load circuit is connected to the upper terminal of fuse 3. The neutral is directly connected from the power source to the load circuit.
Read Also:
Fuse Connection Diagram and Wiring Procedure
Reviewed by Author
on
November 04, 2021
Rating:
Reviewed by Author
on
November 04, 2021
Rating: