Flickering/dimming lights

[Tony B.]

Hi all,

I have a newer home built in 2003 with a 200 amp service. I have an espresso machine that has a PID controller installed on it... The controller switches the water boiler power on and off about once a second to maintain a certain boiler temperature in the machine...

The small espresso machine appliace has a 1100w boiler.. the appliance draws 8-10amps. When the PID controller flips the boiler power of this device on and off in 1 second intervals, I notice all the incandescant lights in my house tend to pulsate along with the power switching from this small 8-10 amp device...

The device is plugged into a 20 amp circuit. There are only 2 outlets on this circuit, and the other outlet is not used...

Now please also understand that the "pulsating" is very hard to notice... it is more pronounced in the lighting runs furthest from my electrical panel where it is just barely noticeable. I just happened to put two and two together a few days after I started using this PID device when I was in the shower one morning and barely awake.. I thought it was just me at first but on further investigation, linked it up with the on/off cycle of the espresso machine. On my can lights in the kitchen (a run closer to my panel), I really have to concentrate to actually notice it. I probably would not notice if it were not for the pulsating rythmic effect generated by the once per second switching.

On other lighting close to the panel, it is either hardly noticable or non-existant.

Is it common or acceptable for lighting on other circuits to feel the effects of a small device such as this? Is this something I need to be concerned about or is it just a minor annoyance...

Thanks for any advice you can offer..

Tony B.

[RBM]

If turning on motors like vacuums or oil burners, well pumps, or 120 volt heating devices like hair dryers, etc also causes this dimming,on circuits other than the ones that these devices are connected to, I would have the neutral connections to your service equipment checked

[Joseph Meehan]

Some might be normal, that depends on how sensitive you are. However I would want to make sure there is not a neutral problem.

Are those lights that are flickering on a dimmer? If so remember that dimmed lights are more sensitive to this kind of situation.

[Ralph Mowery]

An 1100 wattt device is not really small. While it may be drawing an average of 9 amps, it may really be drawing a peak of much more as it cycles . When a device turns on it will cause a small voltage drop and when it turns off, the voltage goes back up. Most devices in the house are turned on and not back off for a while. That is probably why you don't notice it that much. It only takes a small voltage reduction to make a noticable change in the light output.

[Tony B.]

I have a microwave oven in the kitchen that is on a different circuit than the espresso machine... I had my daughter start and stop the microwave every second or so while I watched the lights in the bathroom..

I get the same effect from the microwave powering on and off... very very subtle "flicker", more like a very slight dimming and return to normal brightness within in a few milliseconds.. the lights never flicker to competely off then on.. just a very minimal dimming for a few milliseconds. I really have to concentrate to see it. The lights always return to full brighness once the appliance is running. Same with the espresso machine.. If I switch the boiler heater to full on, it makes the lights "dim" for that millisecond only at the start of the heating element... the lights are at full brighness when full on.

In the case of the espresso machine, the power cycling in a regular pattern once a second or so and makes this dimming more noticeable.

If not for the rythmic nature of the dimming, I'd never notice it's ocurring.

My Garbage disposal also causes my lights in the house to dim slightly when I first flick it on as well.. but more noticeably than the espresso machine, and it's on it's own 20 amp circuit.. Lights dim very slightly for a 1/2 a second then back to normal once the disposal is running... I guess I never even noticed that either but I'm sure it was happening all the time.

Wouldn't that be somewhat normal behavior, even for a 200 amp service? I'm hoping so.. but now that I'm noticing it maybe I'm just getting paranoid... if not for the pulsating effect of this appliance, I would never have given any of it a second thought.

Maybe I don't even need to worry about it... like I said it's hardly noticeable, and always returns back to normal once the appliance is operating. Definately better than my old house with a 100 amp service.. Am I off base here? Does anyone think I need to have this checked by an electrician?

Tony B.

[Tony B.]

I am thinking you are probably right... I would never have even noticed this voltage drop/light dimming if not for the pulsating nature of the appliance. It went for a few days with out me noticing actually.. I only noticed one morning when I happed to be looking at the bathroom light half asleep and thought it was just because I woke up... then put two and two together and linked it to the espresso machine.

Are you thinking this is pretty much normal and nothing to be concerned about? Any idea how this may affect other more sensitive devices like televeisons or movie projectors? I'm not too concerned about it for short term usage, but I sometimes like to let the applicance idle for a few hours, and am wondering if the pulsating for longer periods would affect other devices in the house.

I don't even notice the dimming on the lights in the living areas or kitchen unless I'm trying to because it's that subtle.. just the bedrooms and bathrooms since they are furthest from the electrical panel, and even those are so minor to bother me unless I'm paying attention to it.

Tony B

[Fpbear II]

From the responses to my own thread below.. this seems to be a very common problem, bad ground/neutral if the voltage drop/spike is more than just 5 volts. Have the neutral connections checked in the service panel, and especially the grounding to the ground spike or pipes from the service panel. Could also be on the electrical company pole side of things... Search "floating neutral service panel " or "bad ground service panel" on Google.

[RBM]

Motor loads will typically cause a slight dimming due to their high starting current, and depending upon the size of your electric service, the distance you are from the transformer feeding your service, and the electrical demand on your service at the time this occurs, the dimming may be more pronounced. It doesn't sound like you necessarily have a problem, but you may want to contact the manufacturer to see if this is a common complaint

[Don Young]

Everything you have described is perfectly normal. The effect can be greater or lesser depending on the wiring system.

Don Young

[Wayne]

replying to Tony B., Wayne wrote: I just got a new expresso machine with a pid that does the same thing with dimming lights. I can put the pid in idle mode until I need to make an expresso or just turn off the machine once I have made one. I will get the nutral checked although my previous machine did not do this dim mining thing. LED lights, tv, etc. are not affected by the expresso machines operation, just the incandescent lights are.