Aussie from NSW here - We recently changed our lounge room light fixture to a modern 6 bulb setup, connected it up to see the nightsun that it was at 640lm per bulb.

We quickly installed a dimmer only to find that around 5 am and 8:30 pm we get a major flicker in all 6 globes. The other LEDs in the house don't have this issue.

I'm putting it down to the Off-Peak power signal being flashed down the line as its a pulsed flash, but the question is; how to correct it?

The GE bulbs are dimmable.

  • Sounds like something to do with ripple control
    – user253751
    Jan 29, 2020 at 10:58
  • See also support.environexus.com/hc/en-us/articles/… (this page says it can cause damage, but I don't believe that anything is damaged in your case, it just sounds like an annoyance). They say you can buy filters to suppress the ripple frequency.
    – user253751
    Jan 29, 2020 at 10:59
  • 1
    What type and brand is the dimmer? Many dimmers are not led compatible. Some LED dimmers do not work with all lamps. These issues are common.
    – Ed Beal
    Jan 29, 2020 at 14:37
  • Those bulbs are your problem, for sure. Most LED string filaments like that will have the same issue. They also tend to flicker quite a bit, despite looking really nice. A single regular bulb in the fixture would solve it, but with 6 slots, that's going to look ugly (if it had 3 or 5, you could put a regular small tungsten in the center slot and maintain symmetry). You can simply add a resistor or other constant load to the circuit, but I can't assume most people will be able to do that safely. I would try out several fancy led bulbs and hope one works, but be willing to settle for tungsten.
    – dandavis
    Jan 29, 2020 at 20:14

1 Answer 1


As @user253751 says - it sounds most like the effects of ripple control signals - high frequency tones used to turn off and on hot water heating and other low priority loads.

Even if it IS ripple control related - it MAY be an interaction between bulb, signal and dimmer. If you place one of the new bulbs at a location where the other LED bulbs do NOT cry out to you, does the effect persist.


Here are some Australian sources of ripple control filters - and DIY with off the shelf components may be feasible. Also, local electricians should be aware of the effect if it is ripple control related.

Google search here

Here is a purpose designed $75 Australian solution. Hunter Pacific ZF-1050 Notch Filter Noise Suppressor

enter image description here

This is far far far too dear for what's inside - but may help.

Note from here

  • " ... 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. ... "

Useful comment on page 14 here - related to fans but probably relevant

  • Throughout Australia, but in particular Sydney ... NSW ... , electricity distributors use a remote control and switching system that is commonly called ripple control. ... Ripple control systems superimpose signals on the 50 Hertz mains ... Electrical equipment such as televisions, toasters, fans, fluorescent and halogen lighting and some appliances may be sensitive to ripple control signals. This results in an audible buzz being generated whenever the signals are present. As different frequencies for these signals are used in different areas, products may respond is some areas and not others. Some areas have more than one ripple control system in operation and different signals may be present at different times and affect different products."

  • Also: " ... In areas that have ripple control installed for off-peak tariff switching (such as off-peak hot water systems) there is usually a dual tariff meter installed, or dual meters. A smaller control box marked “Zellweger” may also be present. The meter or Zellweger box will usually have the ripple control signal frequency marked on it (for example 1050 Hz)."


It's likely DIY enthusiasts will have established components suited to ripple control filtering. A suitable series inductor (maybe a fluorescent light ballast) and a suitably rated across-mains "X" capacitor of the right values may well be adequate. Off the shelf components designed for residential mains installation are available.

Another possible solution (YMMV) is to use a suitably rated 1:1 ration "isolation transformer" to feed the lighting circuit. This may work by itself or with a following across mains X-rated capacitor. [ Capacitors connected across mains phase to neutral MUST be rated for such service. X-rated caps (a real term :-) ) are intended for this use. ]

  • That info is great, using your comments has led me to also find more info from a nsw gov site: energy.nsw.gov.au/media/1901/download (page 113 onwards). It shows the basics of developing a signal bypass circuit for eliminating the rippple. See also: elec.uow.edu.au/apqrc/content/factsheets/…
    – mbobbar
    Jan 30, 2020 at 10:34
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    @mbobbar The first reference is very interesting. In your case the $75 commercial unit may represent best balance between effort and cost. May. | Note as I suggested - ensure that the issue IS ripple control and dimmer and bul;bs of interest before spending $. Jan 30, 2020 at 10:41

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