Ripple Control Explained
Ripple control is a way in which electrical companies use a superimposed frequency on standard 50Hz AC power supplies, which are commonly found in most (if not all) Australian households. You must be asking yourself now, "But what does THIS mean?"
Simply put, electrical companies are controlling and managing off-peak power load on their distribution networks. The frequency is used to control hot water heaters, street lights and water pumps through their remote receiver to control the power going to and from each utility. Ripple control may also be used to signal high network load periods for major customers to allow them to reduce power consumption.
What are its Effects?
A hum or buzz from electrical appliances is the most common complaint arising from ripple control, which is generated when a transformer or the motor windings in a switched-on appliance resonate with the ripple control frequency, usually between 300Hz and 1300Hz. The noise is often, but not always, intermittent depending on when the ripple control signals are being transmitted.
People often notice it most acutely in the night when off-peak hot water systems are turned on.
How will I be Affected?
Ripple control frequencies are commonly used in NSW, south east Queensland and New Zealand, although other areas within Australia also use this technology. Not all properties are affected by ripple control, so just because you might live in one of these areas, does not mean that you will have these problems.
One of the only ways to confirm if the area you live in is affected by ripple control frequency is to contact your power company and ask them directly. If you have a system that uses ripple control signalling you might also see a ripple control receiver wired into the fuse box and a dual tariff meter or dual meters.
NOTE: The presence of a ripple control signal does not necessarily mean you will experience ripple control noise in ceiling fans.
What can be Done About the Noise?
Ripple control signal filters are available to manage the noise generated by affected electrical appliances. The ripple control filter must be matched to the local signal being output by your electrical company, usually 750Hz or 1050Hz (information of which can be acquired through your electrical company), and must be installed by a licensed electrician.
There may be extreme cases where the ripple control frequency is so strong it requires two filters to be installed to reduce the noise sufficiently and in some locations multiple ripple control frequencies are used also requiring multiple filters.
Why Doesnt Martec have Ripple Control Filters in their Fans?
Ripple control noise is not the norm and in many environments where it does occur it is not a problem because the noise generated is not audible. While Martec does sympathise with the few customers who do experience a problem, it is not cost effective to build an AC electric motor that rejects all ripple control frequencies given the small proportion of people affected, a cost that would have to ultimately be borne by all consumers.
Its not Ripple Control Noise. What Else Could it Be?
If you are hearing the tones at random times of the day, your electrical supply may be affected by harmonics; a power fluctuation that is not part of the normal electricity supply or ripple control signal output. Harmonics are caused by an interference created by other equipment on the network, such as inverter type air conditioners and switch mode power supplies for computers.
The offending appliances may be in your home or other premises on the local power grid. If you are being affected by network harmonics, it may be of benefit to transfer the electricity supply to your premises to a different phase in the street. This is something you will need to discuss with your electrical company.
Will my Warranty Cover Ripple Control or Harmonics?
Ripple control and electrical harmonics noise is not the result of a mechanical fault with your ceiling fan. As such we do not cover either occurrence under our warranty. Where ripple control noise is found to be at fault, the customer will have to acquire a filter and have it installed by their electrician at their expense.
If you make a warranty based service call and ripple control or electrical harmonics noise is diagnosed as the problem you may be charged the call-out fee for the electrician.
You can view a copy of our Warranty or download a copy of the PDF .