Lights flickering 1

[AusLee]

Hi,

What can be causing these lights to flicker?

1:

https://www.dropbox.com/s/9wyc7vck7n7dkex/Defect #1 - garden lights.MOV?dl=0

2:

https://www.dropbox.com/s/cj6or3x1awmdhnu/Defect #2.A - garden lights.MOV?dl=0

3:

https://www.dropbox.com/s/2w5qvjfilonxzqi/Defect #3 - outdoor awning.mov?dl=0

Thanks

 

[FacEngrPE]

Only one light in a group, something local to that lamp.
Possibly a bad ballast or LED driver. Next choice is a loose wiring termination at the lamp, but I think the defective lamp driver is more likely, are they still under warranty?

 

[AusLee]

For the loose wiring termination, am I correct in understanding it this way: the loose connection is causing a high impedance contact with the power supply, therefore reducing the applied voltage. With the reduced voltage: the capacitors in the ballast do not have sufficient time to charge hence this low-frequency puslating glow. The only problem I have with this interpretation is that the connection at the terminal is a very short distance, so no matter how bad it is: over the very short distance it is not possible that it can cause a high impedance. Are you able to please elaborate how a loose connection would cause this?

No the lights are all out of warranty.

 

[3DDave]

Over a short distance - yes there can be a high impedance. That's how fires start at bad connections.

 

[jghrist]

I've had LED lights flicker in my house for no apparent reason. I replaced the bulbs with another brand. See

https://lamphq.com/flickering-led-lights/

 

[Compositepro]

I recently experienced flickering LED bulbs in a bathroom. The issue was a loose connection on the main breaker, which was not identified until the breaker tripped from overheating. Other LED bulbs in the house were not noticeably flickering, so it appears to depend on the brand of bulb.

 

[TugboatEng]

LED bulbs need filters to prevent strobing on AC power. Some filters are better than others. A good filter may be able to filter out an intermittent break in the circuit.

Also, this installation appears very new and you are on the left end the bathtub curve. Consider swapping in a known good unit to rule out the fixture itself.

 

[Comcokid]

Twice I've noticed incandescent lights flickering in two different houses. In both cases it was traced back to a circuit breaker that was going bad and heating at the contacts.

 

[RRaghunath]

One of the reasons for flickering is missing or loose Neutral connection.

 

[AusLee]

Hi,

I got 2 other videos:
Video 1
Video 2

This is high frequency and different in kind from the first flickers which appear to be voltage drop issue due to high impedance / loose connection.

I have a feeling it is due to the controlled-load frequency that the supply authorty delivers in the area: this high frequency interposed over the base frequency is used to communicate with the meters for controlled load and remote reading maybe.

Any ideas?

 

[stevenal]

If you can see it, it is not high frequency.

I would tell this authority what you are experiencing, and see if they'll take some readings and provide some analysis and possible correction.

 

[AusLee]

@stevenal thanks for your reply, there are a lot of apartments in the same building that are not experiencing any flickering. Also these are LED lights not incandescent: the incandescents back in the day used to have 'thermal inertia' to ride through frequency canhed, for LED: it all depends on the capacitor. Say an LED is 10W, at 12V DC: this means 830 mA in total <- changes in voltage have much higher impact for LED than for incandescent. The supply authority will say it's nmot their problem as other similar apartmens have no flickering. If you have a look at the first videos in the original post, i meant to compare the frequency with those: it is 'higher' frequency I suspect the tone frequency on the grid is 790 Hz if that helps

 

[3DDave]

Looking at

https://pixiepartners.com.au/how-to-fix-led-lights-flickering-in-australia/

the problem might not be the lamps but the reaction of lamp dimmers; one suggested solution is to just remove the dimmers and use switches. They also suggest using noise filters which might be expensive.

See also:

https://www.led-drivers.com.au/blog/ripple-voltage-injection-may-cause-led-lights-flicker

Sounds like you are screwed without potentially expensive changes. I doubt the Supply Authority will change this.

 

[stevenal]

Good point. I've seen even "dimmable" LEDs strobe when on a dimmer.
Even if they don't fix it, your power supplier should be able to take readings. Where I live, there is generally no charge.
Does this occur constantly? Certain times of day?

 

[3DDave]

To skip a step - the OP apparently lives in Australia where someone decided to use +/-6V variations in the signal to allow the power company to communicate with water heaters that evening/overnight power rates were lowered. This was a great idea maybe 50 years ago and it's cheap. What I don't understand is how long this runs for, but it would seem like only a few minutes as the randomized startup is done by the water heater receiver so it's not like they are working through the address space over hours long periods.

"In some parts of Australia power lines are injected with a ripple voltage, or pulse. This can be at a frequency ranging from 167Hz to 1050Hz and is also known as the Zellweger ripple or audio frequency injection control (AFIC).

The below image shows the impact of a 1050 Hz signal with a magnitude of approximately 6V (2.6% of 230 V) on a waveform measured in the field. " from

https://www.led-drivers.com.au/blog/ripple-voltage-injection-may-cause-led-lights-flicker

 

[AusLee]

@3DDave thanks, you are right, and for the first link you sent I did contact SAL and asked them if the filter is in t he SDD 'dimmer' or if i just get the SFI downlights then they will include a filter as well: they said the lights will be flicker immune even on manual ON/OFF switching not dimmer.

It appears that when the line voltage is 230V, the 6V does not make much difference, but when people start to use dimmers and reduce the voltage, the impact of the 6V becomes much more pronounced: hence they included the SDD in the PDF but the filter is actually in the light.