Category: RCD’s

What is the difference between Fuses, circuit breakers, RCDs and RCBOs? While all of these provide protection, how do they differ and what are their specific functions? The function of Fuses, circuit breakers, RCDs, and RCBOs are all protective devices used in electrical systems, but they have different functions and mechanisms. Here’s a breakdown of each:

Fuses:

Function of a Fuse

A fuse provides overcurrent protection by breaking the circuit when the current flowing through it exceeds a certain level. The fuse contains a metal wire or strip that melts when it gets too hot, effectively interrupting the flow of electricity and preventing damage to the rest of the circuit.

How the fuse works

The fuse “blows” when the current exceeds its rated capacity, creating an open circuit. Once blown, the fuse must be replaced.

Protection Type that the fuse gives

Overcurrent protection (against excessive current)

Disavantages

Simple, inexpensive, and effective.

Advantages

Once blown, fuses need to be replaced, and they do not provide protection against faults like earth leakage. Old technology.

Circuit Breakers

Function of a circuit breaker

A circuit breaker is an electrical switch that automatically interrupts the flow of current when an overload or short circuit occurs. Unlike fuses, circuit breakers can be reset after they trip.

How the circuit breaker works

Circuit breakers use thermal or magnetic mechanisms to detect overcurrent. When an overload or short circuit happens, the breaker trips (opens) to stop the flow of electricity.

Advantages

Reusable (can be reset), more convenient for handling repeated faults, and offers faster response time than fuses.

Disadvantages

More expensive than fuses, but they don’t protect against earth leakage.

What does your Electrician mean when they are talking about Fuses, circuit breakers RCBO’s, and RCDs

When your electrician mentions fuses, MCBs, RCDs, and RCBOs in your switchboard and you’re unsure of their meaning. Don’t worry. In the following section, we will outline the differences and explain how each one works in detail.

Fuses and MCBs

• Fuses and MCBs – that is, miniature circuit breakers. Both “blow” when the current exceeds a limit. You can reset an MCB after fixing the fault, while you must replace a fuse.
• A fuse is basically a piece of wire between two contacts to make a circuit. When current flows, heat is produced and the wire gets hot. If too much current it produced the wire melts and the circuit is broken. There is nothing you can do, the fuse will need to be replaced.
• A miniature circuit breaker, uses an electromagnet to break the circuit if the current is exceeded. It also has a toggle on the front so that it can be reset. The MCB is generally more reliable than a fuse and reacts quicker.

What is an RCD (Residual Current Device)

A RCD – (Residual Current Device) is a sensitive safety device that switches off the electricity within 10 to 50 milliseconds if there is an electrical fault. An RCD protects against the risks of electrocution and fire caused by earth faults. RCDs protect persons from death or injury by electric shock.

Your home may have circuit breakers installed, but these only protect against overloading and short circuits – not electrocution. 

How does the RCD work?

You can install an RCD at a dwelling’s switchboard (power box) or at the first light or power point in each circuit. All RCDs have a test button that should be pressed every three months to simulate a fault and indicates whether the RCD is operating correctly. 

Do you need an RCD (safety switch) installed?

RCD’s (Safety switches) Save Lives. Safety switches immediately turn off the power if they detect an electrical fault, preventing the risk of electric shock, death, and fire.

NSW Government RCD Consumer Safety Campaign

The NSW Government has launched a campaign to educate consumers about the importance of electrical safety in and around the home. NECA is part of the NSW Government’s cross-industry partnership between government, non-government and industry organisations, which will help reduce risk and potentially save lives.

Each year, electrical faults and appliances cause 40% of the 4,500 home fires in NSW. A licensed electrician could have prevented these fires by checking electrical wiring and installing safety switches. The NSW campaign will focus on promoting actions homeowners can take, such as having a licensed electrician check the home, have electricians install safety switches, and testing them regularly.

As part of the partnership, NECA will work with members to support outreach to homeowners about electrical safety. IS YOUR HOME SAFE? ELECTRICAL SAFETY TIPS EVERYONE SHOULD KNOW click the link to download the brochure is Your Home Safe?

The cost of installing a RCDs?

The cost of installing a single RCD will depend on the size of your switchboard and how many circuits need to be upgraded.

How do you know when you need a switchboard upgrade?

When a switchboard upgrade is recommended is if your current switchboard has old ceramic fuses and an asbestos panel. outdated switchboards are dangerous and you could possibly be putting your family at risk. Our electricians will recommend the need to invest in a switchboard upgrade with RCD’s.

An upgraded switchboard will mean you will have a switchboard that meets the current Australia standard. Upgraded switchboard will have safety switches and circuit breakers installed throughout the board and the board will be clearly labelled. RCDs (Safety switches) installed in your switchboard are a safety device that prevents electric shocks by detecting leakage currents and cutting off power. It works by measuring the current flowing in and out of a circuit and cutting off electricity if it detects an imbalance.

South Coast Electrical Solutions can have an electrician inspect, repair or replace your switchboard in the following suburbs.