Flickering lights when dishwasher running

Location
Washington
Occupation
Journeyman 02
So I did a full rewire at an older home (40’s). The flipper didn’t want to update the service if not necessary it was a newer maybe early 2000’s Eaton panel. When the customer turns the dishwasher on the kitchen cans flicker. They are on a diva dimmer (led compatible) and the can trims are just standard 3k led trims. Can’t seem to figure out every connection is solid at the panel, not getting any irregular voltage to anything. Obviously dishwasher is on its own dedicated circuit separate from lighting. There is a switch box that both circuits are in and I’m wondering if the dimmer is ultra sensitive to the current pull from the dishwasher motor. Any advice on how to fix this have t really ran into it before. But main service and connections seem solid. Maybe move my arc fault lighting load to a separate pull as the dishwasher ? Replace the dimmer? Replace the AFCI breaker? No other lights in the home are having issues
 
This is a common problem with LED lighting. Try replacing the dimmer with a switch to rule out the dimmer if you want. How bad is the flicker? People are used to incandescent lighting and when their LED lighting flickers once and awhile its cause for alarm. Sometimes you just have to live with it because there is no cure. Chalk it up to progress.

-Hal
 
If the lights only dim or flicker when the dishwasher is started than it is inrush and if it is while the dishwasher is running than you could have more than one dirty load on that leg that is creating the issue. Like an electric water heater or insta-hot and with both going at the same time it is enough to get the voltage distorted for the lights.

Verify that they don't share the same neutral back to the panel. Move the lighting circuit to the other leg. Verify the dimmer, LEDs and fixtures are all rated to work together. That they are compatible.

The cheapest solutions are usually to replace the light bulbs with better ones, replace the dimmer, etc. The more expensive are the capacitors or replacing the dishwasher.
 
Thanks
If the lights only dim or flicker when the dishwasher is started than it is inrush and if it is while the dishwasher is running than you could have more than one dirty load on that leg that is creating the issue. Like an electric water heater or insta-hot and with both going at the same time it is enough to get the voltage distorted for the lights.

Verify that they don't share the same neutral back to the panel. Move the lighting circuit to the other leg. Verify the dimmer, LEDs and fixtures are all rated to work together. That they are compatible.

The cheapest solutions are usually to replace the light bulbs with better ones, replace the dimmer, etc. The more expensive are the capacitors or replacing the dishwasher.
Thanks yea they are cheaper end supply house can trims I mean 6-8$ a piece. I’ll try some higher end and I’ll check and see if they flicker on a regular switch. Super annoying it’s not an intense flicker but this homeowner is incredibly picky
 
This is a common problem with LED lighting. Try replacing the dimmer with a switch to rule out the dimmer if you want. How bad is the flicker? People are used to incandescent lighting and when their LED lighting flickers once and awhile its cause for alarm. Sometimes you just have to live with it because there is no cure. Chalk it up to progress.

-Hal
It’s not bad at all these people are just extremely anal. But they pay a lot lol so trying to figure out how to make them happy in the end. I’ve dealt with shared neutrals and the standard flickering but never really this. Thanks for the input I’ll mess around with a few things I thought about changing the dimmer sensitivity as well
 
Thanks for the input yea it’s all new wiring I did so lights are all separate on their own neutrals, dish and dispo on their dedicated circuit together. I’m going to try and move it to the other load and hopefully that helps. I’ll give. Standard switch a go and see if it’s the dimmer.
 
Impulse and transient response characteristics are not part of defined specifications for general purpose L.E.D. ballasts.

Working voltage range and transient response are two separate matters. 120-277v ballasts can operate from 108 to 305v range with a constant output. There are some older T8 fluorescent ballast with excellent transient response that you could plug it into the end of a 16 AWG extension cord with a compressor and you won't notice a dip while other ballasts will flicker badly.

Power supplies that feed power to sensitive electronics and must share the power source with the load, such as the control board on a window AC unit or an inverter welder is designed with transient response in mind... but general LED ballasts, no.

This is due to the way the L.E.D. ballast and the dimmer are designed, and how they interact with each other.
 
Why do you refer to the LED drivers as ballasts? I've never heard anyone call them ballasts, only heard drivers.
A lighting ballast is an electrical device that regulates current and voltage supplied to a light fixture. Which is exactly what a driver does. Few and far between, but I have heard the term Ballast used synonymous with Driver in the LED world.
 
Why do you refer to the LED drivers as ballasts? I've never heard anyone call them ballasts, only heard drivers.
Because, I can.

Every LED should be fed with a controlled current. Some use a combination of a ballast and a voltage source/"power supply".

The simplest ballast is a series resistor. Many tape lights use a 12v or 24v DC voltage source/AC adapter, but has a ballast for each of the string within the tape, usually a plain resistor in series. There's rarely any LED that is truly ballast-free.

A few exceptions are like coin cell driven keychain lights where the internal resistance of the coin battery acts as the current limiting ballast. So called ballast bypass lamps simply means the ballast is installed within the lamp. There's no user accessible ballast, but that doesn't mean they don't experience ballast related complications.
 
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