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Flickering lights? It could be Ripple Control
Do your lights flicker or fans hum at a regular time each day? It could be a side-effect of ripple control. Learn about what ripple control is, how it works, and how to prevent related issues below.
Ripple control, AKA Ripple voltage injection or Audio frequency injection occurs in parts of QLD and NSW (and other regions around the world) where the energy operator temporarily injects a high-frequency carrier signal into the energy supply that can be detected by certain devices to control their operation. This is used by the energy operator to manage load during times of peak demand and to switch certain devices on during off-peak times. It is often used to control hot water systems, solar systems, street lights and heavy industry.
Australian mains power is 230-250V at a frequency of 50hz. Ripple control is when the energy operator sends a signal through the lines at a higher frequency that can be detected by smart meters or ripple signal detectors. The exact frequency of the ripple signal depends on your location and the system used by the energy operator in that area.
In South East Queensland, for example, Energex use a 1050hz ripple signal. Elsewhere, 750hz and 492hz signals are also used.
A side-effect of ripple control is the potential for unstable operation of certain electrical devices due to the temporarily distorted energy supply. The severity of effects can vary based on where you’re located and the type and configuration of affected devices. Ripple signals typically last for a few seconds or minutes but can run longer in some areas.
Effects on LED lights can range from a subtle flicker to strobing and tends to be more common in LED lights with phase-cut dimmable drivers and those that are connected to and being dimmed by a dimmer switch.
Ripple signals can also cause AC fans to emit a slight humming noise and for distortion to come through stereos and speakers.
On the other hand, a ripple signal that is too weak can fail to be picked up by ripple signal detectors, resulting in devices not operating when they should, such as a hot water system not switching on overnight.
Issues with ripple control are not uncommon and can be difficult to treat. The signal can vary heavily in strength from area to area due to distance from the source and the potential for harmonic resonance in the network.
If you think issues with your electronics could be due to a ripple control signal, look up whether your energy provider uses ripple control or contact them to enquire directly.
As LED lighting connected to a dimmer switch can be susceptible to ripple interference, either don’t use the dimmer during ripple control periods or have it removed if it isn’t necessary. Quality drivers that use digital dimming protocols such as DALI are less susceptible to ripple and some drivers claim to include ripple filters, though results can vary.
Ripple filters can be installed on specific devices or on circuits at the switchboard. These are tuned to a set frequency, so make sure you get the right filter for your area and have it installed by a qualified professional. Nonetheless, manufacturers of these devices state they aren’t a guarantee, and may only reduce symptoms rather than eliminate them entirely.
It’s worth mentioning that ripple control is not a globally-used technology, and the Zellweger ripple method used in Australia and New Zealand is only a sub-type of ripple control technologies. This means that cheap products produced overseas will usually make no allowances for ripple signal interference, so sticking to quality products from Australian manufacturers when you can, is a safer choice if you live in an area that employs ripple control.