Scene: 700 sq ft apartment. Two general lighting and convenience receptacle circuits.
Problem: When a laser printer is in use the lights flicker.
What causes this? Is there an easy fix? This is a brand new printer. Several have already been returned to the store where purchased. All returned printers have the same problem. Interesting. Any ideas?

Do you mean the lights are 'dimming'??

Did you check the amperage of the printer?

Sounds to me like the receptacle outlet that the printer is plugged into, and the lights are on the same circuit. Try a different circuit.

Also, there may be a loose connection somewhere; at the panel, main, meter, or POCO connection.

There's nothing wrong with the printer, they just draw a lot of current. I have a Xerox Phaser 6100 color laser that's rated at 10 A. The flickering you experience is probably caused by the fuser lamp turning on, to heat up the fuser rollers. It takes a lot of heat to melt the toner into the grain of the paper. Of course, there is also HVDC in there which makes the toner stick to the paper in the desired pattern before it goes through the fuser.

Yup, absolutely normal, noderaser is spot on. You can try a dedicated 20A circuit but my experience is that sometimes you will still notice some flickering even on other circuits.

-Hal

I'm with HotLine - think maybe your panel is in need of a minor service. This would include checking breaker seating, cleaning contacts, and snugging up all the lugs - including the mains/feeders.

Even with the high draw of the printer, flickering or dimming lights is usually a sign of limited current availability due to higher-than-normal resistance somewhere in the circuit(s).

Good Luck!