LED bulbs flash during ISY traffic

[thrang]

I have an odd situation - I'm using Feit T10 tubular Edison style LED's in two handing pendants, the load controlled by a keypad and slave switch. When there is ISY traffic, the lights flicker badly. I use the same bulbs (five of them) in a different fixture, also controlled by (another) keypad load button, and they never flicker due to ISY traffic (though there are four additional 40 incandescents on the same load as those five.

Can this be a resistance issue? Can low resistance allow ISY traffic to cause LED bulbs to flicker? What's odd is in my kitchen I have a circuit with two retrofit LED hi hats and thats it (connected to a dimmer switch), so thats a very low resistance - and they don't flicker during traffic.

I installed one of the Lutron LED load resistors on the circuit to increase the load but that's not helping - should I parallel a second one, or is this indicative of another issue?

I have about 30 Insteon switches installed on many circuits, and generally all ok - a few others have occasional flicker of LED fixtures, but they are unrelated to ISY traffic.

The only think I recall is my electrician noted the load was originally at the slave location, so he used an available traveler wire to move the load to the keypad unit. Could this impact the issue? I presume the fixture needs to be on the keypad load, but is that not correct? I can have him revert...

 

Thanks

[Teken]

10 hours ago, thrang said:

I have an odd situation - I'm using Feit T10 tubular Edison style LED's in two handing pendants, the load controlled by a keypad and slave switch. When there is ISY traffic, the lights flicker badly. I use the same bulbs (five of them) in a different fixture, also controlled by (another) keypad load button, and they never flicker due to ISY traffic (though there are four additional 40 incandescents on the same load as those five.

Can this be a resistance issue? Can low resistance allow ISY traffic to cause LED bulbs to flicker? What's odd is in my kitchen I have a circuit with two retrofit LED hi hats and thats it (connected to a dimmer switch), so thats a very low resistance - and they don't flicker during traffic.

I installed one of the Lutron LED load resistors on the circuit to increase the load but that's not helping - should I parallel a second one, or is this indicative of another issue?

I have about 30 Insteon switches installed on many circuits, and generally all ok - a few others have occasional flicker of LED fixtures, but they are unrelated to ISY traffic.

The only think I recall is my electrician noted the load was originally at the slave location, so he used an available traveler wire to move the load to the keypad unit. Could this impact the issue? I presume the fixture needs to be on the keypad load, but is that not correct? I can have him revert...

 

Thanks

From a tiered approach you can try the following given your time vs reward.

- Air Gap: Pull the air gap and wait ten seconds and see if the problem goes away or remains.

- Insteon TX / RX: Some of the newer Insteon hardware allow you to enable / disable different levels of signaling such as errors turn any of them off if present.

- Remove one of the T10 from the fixture and see if the remaining bulb flickers. If so insert a standard bulb and repeat and see. 

- Load Resistor: You can certainly place another one in parallel but one could be at the switch vs the load if you decide to do so.

- Replace: If none of the above works you have limited choices besides switching to another brand / model and testing again. You could also remove the other bulbs that don't flicker and swap them to see if they also flicker. if they flicker there and not in the other you know this is a load issue and as noted you could try adding another Lutron LED resistor.

- Snubber: A similar device normally used to prevent damage to a Insteon device is a RC-Snubber. The primary goal of this device is to limit the CEMF or reverse current being injected into a target device. These devices (RC-Snubber) are normally used on items that have relays / motors such as a ceiling fans.

- Relay vs Dimmer: if the load doesn't need to be defined to set a mood / save energy. You may consider switching over to a Insteon Relay switch as they normally aren't impacted by this issue but your mileage may vary!

[thrang]

20 minutes ago, Teken said:

From a tiered approach you can try the following given your time vs reward.

- Air Gap: Pull the air gap and wait ten seconds and see if the problem goes away or remains.

I'll try this again

- Insteon TX / RX: Some of the newer Insteon hardware allow you to enable / disable different levels of signaling such as errors turn any of them off if present.

Dont see this, and the keypad (load) is maybe three months old. I see:

- Remove one of the T10 from the fixture and see if the remaining bulb flickers. If so insert a standard bulb and repeat and see. 

If I leave one T10 LED in place and use an incandescent in the second fixture, I don't see the problem. So perhaps it is a low load issue?

- Load Resistor: You can certainly place another one in parallel but one could be at the switch vs the load if you decide to do so.

Sorry not sure what you mean by one at the switch and one at the load. The one I'm using is in the switch box, connected inline between the hot and neutral per LUT-MLC instructions

- Replace: If none of the above works you have limited choices besides switching to another brand / model and testing again. You could also remove the other bulbs that don't flicker and swap them to see if they also flicker. if they flicker there and not in the other you know this is a load issue and as noted you could try adding another Lutron LED resistor.

I've tried a few different LEDS in this fixture /circuit and they basically do the same thing. They dont flicker once commands are done, its the ISY commands that are causing the flicker.

- Snubber: A similar device normally used to prevent damage to a Insteon device is a RC-Snubber. The primary goal of this device is to limit the CEMF or reverse current being injected into a target device. These devices (RC-Snubber) are normally used on items that have relays / motors such as a ceiling fans.

Not familiar with this, but will research

- Relay vs Dimmer: if the load doesn't need to be defined to set a mood / save energy. You may consider switching over to a Insteon Relay switch as they normally aren't impacted by this issue but your mileage may vary!

Dining room table, so need MOOOOOD.

Thanks kindly...

[Teken]

21 minutes ago, thrang said:

Thanks kindly...

- LED On TX: Turn it off, nothing to lose.

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If I leave one T10 LED in place and use an incandescent in the second fixture, I don't see the problem. So perhaps it is a low load issue?

Yes, highly possible

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Sorry not sure what you mean by one at the switch and one at the load. The one I'm using is in the switch box, connected inline between the hot and neutral per LUT-MLC instructions

The device can be inserted in parallel at the light fixture (load) or at the switch (KPL). Keeping in mind you may try to add another one in parallel. But, suggested try to install the second one at the opposite side where ever the first one is.

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Not familiar with this, but will research

https://www.digikey.com/product-detail/en/red-lion-controls/SNUB0000/RLC201-ND/3596201

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Dining room table, so need MOOOOOD.

Happy Wife - Happy Life: Understood, now Rock On!

[HABit]

I have experienced this problem using LED bulbs with a keypadlinc dimmer. Using the same bulbs on the same electrical circuit using switchlinc dimmer and there is no flickering. I tried to research whether the KPL's use a slightly different dimming circuit, but haven't found anything confirming a difference between the switchlinc's and KPL's. 

Incandescent bulbs emit light because the filament is heated, whereas LED's are quantum devices: Either On or Off. The dimmable bulbs trick the human eye into seeing a dimmed bulb/light by turning the lights on and off rapidly. The brighter the bulb, the more "On" time it is being allowed (PWM). Being essentially semiconductors, LED's switch On/Off rapidly. This makes them more susceptible to fluctuations in the line voltage. The visual problem is worsened since the LED bulb circuitry "translates" the dimmer's voltage into the pulse width, (which is the perceived intensity of the LED bulb). Since both the LEDs in the bulb and its dimming circuitry can respond rapidly, you will see any variation in the electrical line as flickering. Incandescent bulbs don't show flickering since it takes a relatively long time for line voltage differences to be reflected in light output.

Some bulb mfg's improve the resistance to line variations by purposefully slowing down the voltage to PWM change rate. I found CREE bulbs better than others (I was using Feit in the KPL circuit), however at dimmer light levels, the flickering persisted with the KPL's.

Another thing to check is if your light circuit is on an Arc-Fault/GFI breaker. Depending on the mfg of the breaker this can introduce greater susceptibility to power line fluctuations. I live in SWFL where: 1) The power is not good - lots of power line noise and variations; 2) The electrical code requires Arc fault breakers on every outlet. Unfortunately, electrical contractors do not run separate power lines to lights and outlets. I've had to eliminate a few of the Arc faults by running separate lines to improve the noise problems, not to mention the attenuation of insteon PL signals. You may want to check if the flickering LED's are on an Arc-fault protected circuit. Contractor grade Arc-Fault breakers typically are made poorly. Unfortunately, better Arc-fault breakers are more expensive.

I don't know if any of this will help you solve the flickering problem, but at least you'll know that you are not the only one to experience the flickering on a KPL dimmer.

[thrang]

Interesting - I can try moving the keypad to a non-load circuit and see if the other troubleshooting doesn’t work out

I do use a keypad load switch for the same exact lights bulbs on a different circuit, but as noted there are five and not two of them and there are two wall sconces with a total of 4 40 watt incandescent on the same circuit so much more of a load - no flickers with that set Up.

 

thanks

 

[Teken]

@thrang

Regardless of what you do please circle back and let us know what the final solution and outcome is. As this information will surely help another person down the line. 

[thrang]

1 hour ago, Teken said:

@thrang

Regardless of what you do please circle back and let us know what the final solution and outcome is. As this information will surely help another person down the line. 

Certainly will - just might be until next week that my electrician comes in

Thanks all

 

[HABit]

There doesn't seem to be any perceptible difference between the dimming circuitry of a KPL and a switchlinc. Thinking about this, my theory (for what it's worth), is that the KPL has a greater workload on the microcontroller in the KPL, since it also has to scan the keyboard. When insteon message/command traffic comes in, the KPL must also then qualify, decipher, apply the insteon command, so its workload gets greater. This may be enough to change how it is "bit-banging" the dimmer circuit. Since the LED bulb's have a fast response time, you see the change in, essentially, the dimming level, causing the flicker. 

In my case, at least, larger wattage LED's seemed to be less susceptible to the flickering. However, at low dim levels, the flickering is still apparent.

I also note that in some cases where the LED bulb's are located can be a factor. What I'm saying is - I have table lamps in the bedroom on a KPL. I, (mostly my QA department - wife), have not noticed flickering. However, over the Kitchen bar, the flickering was prominent (enough to warrant an official QA notification of failed automation). The kitchen lights are located, in a center area, so changing light intensities are very noticeable. When the night lighting turns on, these bulbs are dimmed to a low (night light) intensity. The bedroom lights are against the wall, out of constant viewing, etc., less noticeable, and not typically dimmed to low levels. I dimmed these lights, and stood close to them with a remotelinc, sending repeated commands, and observed the same flickering. (BTW: Using 11.5 Feit bulbs in lamps).

 

[Erik]

Just tried the LUT-MLC on one of my KPL that has 4 Phillips LED. Normally dimming to 40% is fine. It will dim lower but the LUT-MLC makes a loud buzzing (constant) and with any Traffic still causes a bad flicker. Removed the MLC and will just live with the 40% limit.