Electrical

New RCD laws

Since 2000 it has been compulsory for all new homes to have two RCDs fitted to protect the power and lighting circuits as part of an electrical installation.

In the past 17 years, 29 people including eight children have been electrocuted in homes in Western Australia. Twenty-three of these deaths could have been prevented if Residual Current Devices (RCDs) had been fitted to the power and lighting circuits.

To help reduce deaths from electrocution, the Western Australian Government implemented new RCD regulations in August 2009.

The new legislation applies to people selling their homes and to landlords. Every home sold or leased must be fitted with a minimum of two RCDs which must protect all power and lighting circuits.

When a new tenant takes up residency, landlords will need to install the devices before the lease agreement is signed. However, for homes with a continuing tenancy, landlords have until 8 August 2011 to fit the RCDs.

The regulations can be found here.

Information is provided to assist homeowners, persons selling their homes, landlords, tenants, real estate agents, property managers and electrical contractors on how to ensure homes comply with the new RCD laws.

What is an RCD?

An RCD is a safety device that disconnects a circuit when it detects an imbalance of the electric current. It works on the principle that the electricity flowing into a circuit must be equal to the current flowing out of a circuit. When a person receives a shock, it means some current is diverted through the body directly to earth.

If the RCD detects an imbalance in the electrical current, indicating a leakage to earth, it immediately cuts the electricity supply to prevent electrocution.

An RCD cannot detect all types of faults, for example if a person receives a shock between the active and neutral conductors. However, these circumstances are rare and the vast majority of incidents occur between the active conductor and earth, which is protected by an RCD.

If a person comes in contact with a live electrical conductor, electricity flows through their body, causing an electric shock. Effects can vary from a tingling sensation or muscular pain to breathing difficulties, burns and heart failure.

RCDs are extremely sensitive, disconnecting within 10 to 50 milliseconds of detecting a leakage current. This is usually 30 milliamps for domestic residences but may be lower in other locations such as hospitals. This stops the flow of electricity through someone’s body to earth. Importantly, this response time is much faster than the critical section of the cardiac cycle and therefore significantly reduces the risk of death or serious injury.

RCDs also protect against fire caused by faults in appliances, tools and wiring. If these faults go undetected they could cause a fire or personal injury. RCDs provide a means of early fault detection.

RCDs are required to be fitted at the meter box (main switchboard) or distribution board for the residence.

Various brands of RCDs are available; however they can all be identified by the test button located on the front of the device.

If you press the ‘test’ button, or the RCD has detected an imbalance, the on/off switch will jump to the “off” position.

Circuit Breakers, Surge Protectors and RCDs

Circuit breakers and fuses are designed to protect electrical cables and fittings installed in the home from overloading and short circuits. They cut the power when electrical wiring in the home has too much current flowing through it. They are designed to prevent electrical fires, not electrocution.

Some meter boxes have surge protectors fitted to safeguard appliances against a spike in electrical voltage, such as a lightning strike. Some power boards or extension leads also have surge protectors fitted. These devices do not offer any protection against electrocution.

Only RCDs will prevent electrocution by cutting the power to a circuit in the event of an earth leakage.

RCDs are the only device that can give you or a family member a second chance.

Types of RCD

Meter-box mounted RCDs

RCDs are required by law to be fitted to the power and lighting circuits of new homes and houses for sale or lease.

They are generally located alongside circuit breakers in the main meter box or distribution board of the residence. They can be distinguished from the circuit breakers by the test button.

A minimum of two RCDs are required to ensure some light and power remains if one operates. Two RCDs also reduces the possibility of tripping due to some appliances which have low levels of earth leakage.

Combination RCD & Circuit Breakers

Home owners can choose to install combined circuit breaker and RCDs. These devices protect the electrical circuits and appliances as well as preventing electrocution. Various brands are available.

These combination RCDs are an attractive option for retro-fitting into existing meter boxes with little or no spare space.

Portable RCDs

Portable RCDs attached to a power board or extension lead are available. RCDs on power boards and extension leads only protect the circuits of appliances connected to them. They are essential for people using power tools or electrical appliances outside that are not protected by a meter box RCD or power point RCD.

Power point RCDs

RCDs may be fitted to a power point and can be distinguished by the test button on the face plate. They must be fitted to the first power point after the meter box. They are suitable for protecting electrical appliances in specific areas such as bathrooms and workshops.

Checking if you have RCDs installed

RCDs will be installed in your home’s meter box or distribution board and can be identified by the test button on the front of the device.

Your meter box may only have one RCD installed if your home was constructed between 1992 and 1999 when it was a requirement to have one RCD installed on the power outlet circuits only. Since 2000 it has been compulsory for all new homes to have two RCDs fitted to protect the power and lighting circuits as part of the electrical installation.

One RCD will not ensure complete protection for your family. One RCD is likely to protect only the power circuits and leaves the lighting circuits unprotected.

If you are unsure whether you have RCDs installed contact a licensed electrical contractor.

Testing RCDs

To ensure that the RCDs fitted to your home perform correctly, they must be tested at regular intervals. EnergySafety recommends that each RCD be tested every three months.

To test your RCD press the ‘test’ button on the front of the device quickly and then release it. The button will only test the RCD if an electricity supply is connected.

Pressing the test button will simulate an earth leakage fault and indicates whether the device is operating correctly. When an RCD operates all power is lost to the equipment, power point or circuit protected by the RCD. To restore power simply move the “on/off” switch back to the “on” position. Electrical clocks and timing devices may have to be reset.

If the RCD fails to operate a licensed electrical contractor must be engaged to test the RCD and replace it if necessary.

Follow these simple steps to ensure your RCDs are operating correctly:

1. Plug a small lamp into a power point and make sure it works. Leave it turned on.
2. Make sure that electricity is connected to the property and the main switch is in the on position. The lamp should be on.
3. Turn off all electronic equipment (computers and televisions) etc
4. Push the test button on each RCD. Do not hold your finger on the test button. The RCD should operate (turn off). If it does not operate, it must be checked by an electrical contractor.
5. After pushing the test button and the RCDs have turned off check that the small lamp is now off. Also check that all the lights and power points do not operate. To do this, plug the small lamp into all the power points and turn the power point on. If the lamp turns on a licensed electrical contractor must be engaged to correct the wiring.
6. When finished testing, turn the RCDs back on and check that the lamp works when plugged into a power point.

Nuisance Tripping

Some electrical appliances and old wiring may have a normal small amount of earth leakage current which can trip an RCD.

Earth leakage increases with each additional electrical appliance plugged in, so a single meter box RCD protecting all household wiring is more likely to experience nuisance tripping.

If an RCD trips twice for no apparent reason, have your wiring and appliances tested by a licensed electrical contractor.

Information for Homeowners

A minimum of two RCDs protecting all power and lighting circuits must be fitted to a residential property before it can be sold and the transfer of title takes place. Penalties apply if RCDs are not fitted and the land title is transferred to another person.

If you own a residential property and don’t intend to sell, lease or rent it then you do not need to have RCDs fitted to protect all the power and lighting circuits.

However, RCDs protect you and your family from electrocution. Fitting these devices to all power and lighting circuits in your home can be a life-saving investment and is strongly recommended.

Call a licensed electrical contractor to have RCDs installed. Ask for a no-obligation quote before authorising the electrical contractor to proceed. The electrical contractor will install the RCDs and provide an Electrical Safety Certificate which will state that RCDs have been installed in compliance with the AS/NZS 3000:2007, Wiring Rules. A sample of an Electrical Safety Certificate is here.

The electrical contractor will also notify the network operator that a minimum of two RCDs have been installed by submitting a Preliminary Notice and Notice of Completion. Following the receipt of these Notices, the network operator may inspect the work as part of its monitoring of electrical contractors’ work.