What Is RCD - Residual Current Device?
Residual Current Device (RCD), also known as Safety Switch or ELCB (Earth Leakage Circuit Breaker) is a device that can be on switchboards, power points, or even portable devices. It is a life-saving device that stops the flow of electricity before causing risk to the person involved.
A Little bit about RCD's
RCDs detect electrical flow disruptions through electrical circuits and switch the power off. Electrical flow disruptions are associated with electric shocks, which may be fatal.
The Local Guys technicians visually inspect then test and tag your Fixed and portable RCDs according to the Australia Standard AS/NZS 3760:2022. They make sure that RCDs are working properly and within the time frame by conducting a simple push-button trip test and operating time test.
RCDs are designed to prevent disasters and save lives. It is essential to make sure that they are going to work properly when you need them.
WHS Regulations oblige workplaces to install, inspect, test, and tag RCDs for all circuits, especially in hostile work environments.
Why do I need to test RCD's?
Under AS/NZS 3760:2022, RCDs are split into two types based on how sensitive they are. Type 2 RCDs (rated at 30mA) are the most common in Australian workplaces and must trip within 300 milliseconds. Type 1 RCDs (rated at 10mA) are more sensitive and are used in higher risk settings, and must trip within 40 milliseconds. If an RCD doesn't trip within its required time, it's considered failed and needs to be taken out of service.
What is involved in the RCD Test?
The test has 2 components. These are listed below:
- Push Button Test: This is simply pushing the button on the RCD to make sure it trips. Because RCD's are designed to be so sensitive, it is very easy for the to become faulty. By simply pushing the test button frequently, it will ensure that they will work when you need them to. Quite often this tests fails, but after working the switch back and forward a couple of times it works again. This can be due to a small amount of dust built up in the RCD resulting in it not tripping.
- Timed Test: For this test we will find an outlet on the circuit and plug in our RCD tester. This will send a pulse down the circuit above the rating of the RCD. This will cause the RCD to trip & the RCD tester is timing how long it takes to trip. If it's within the safe time frame, the RCD passes the test.
Who can test an RCD?
RCD’s are required to be tested by a competent person who has been trained in how to properly and safely conduct the test.
If you need more information or want your RCDs tested by a qualified technician, The Local Guys can help. Book an RCD test or contact us if you have any questions.
Frequently Asked Questions
What can cause an RCD to trip?
An RCD trips when it detects an imbalance between the current flowing in and out of a circuit, usually from a faulty appliance, a damaged cord, or moisture getting into an electrical fitting. Frequent tripping without an obvious cause is worth having checked by a competent tester.
Should I leave my RCD switched on or off?
RCDs should be left on at all times. They only trip when they detect a genuine fault, switching one off removes the protection it's there to provide.
How do I fix an RCD that keeps tripping?
A repeatedly tripping RCD usually points to a fault somewhere on the circuit rather than the RCD itself. It shouldn't be reset and ignored. Have it inspected by a competent person to find the cause before continuing to use that circuit.
