OK Experts, I have an issue....yeah I know the obvious solution - move the laser printer - well not possible...
So I have my audio system connected to main circuit that also has laser printer. When I print the printer causes audio dropout. I have tried a few things and can say it is my DAC source (not Tube preamp, or amp, or Quad ESL speakers - all on same mains circuit)
Now my solution would be plug the DAC (AMR DP-777SE) separately into either a 1200VA Voltage Regulator or a 450W Computer UPS...both are looking to be around $60....
I am leaning towards the 1200VA Regulator here:
https://www.amazon.com/APC-LE1200-Automatic-Voltage-Regulator/dp/B00009RA60/ref=sr_1_4?dchild=1&keywords=voltage+stabilizer&qid=1633792307&sr=8-4
Is the computer UPS a better solution, or another solution?
Not looking to move printer, or modify the AMR unit...
Also noticing lately the unit has blips when the AC turns on....
Also problem COULD BE the computer that I have connected to the DAC source being the issue (also on same mains circuit)... losing the USB signal...if solution above does not work, I was planning on just putting computer on the Regulator or UPS....
So I have my audio system connected to main circuit that also has laser printer. When I print the printer causes audio dropout. I have tried a few things and can say it is my DAC source (not Tube preamp, or amp, or Quad ESL speakers - all on same mains circuit)
Now my solution would be plug the DAC (AMR DP-777SE) separately into either a 1200VA Voltage Regulator or a 450W Computer UPS...both are looking to be around $60....
I am leaning towards the 1200VA Regulator here:
https://www.amazon.com/APC-LE1200-Automatic-Voltage-Regulator/dp/B00009RA60/ref=sr_1_4?dchild=1&keywords=voltage+stabilizer&qid=1633792307&sr=8-4
Is the computer UPS a better solution, or another solution?
Not looking to move printer, or modify the AMR unit...
Also noticing lately the unit has blips when the AC turns on....
Also problem COULD BE the computer that I have connected to the DAC source being the issue (also on same mains circuit)... losing the USB signal...if solution above does not work, I was planning on just putting computer on the Regulator or UPS....
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From the first review of the linked to device, kind of looks like it might help or might not. As long as you can send it back if you don't like it then it might be worth a try.
Is it airborne or mains borne ?
Maybe try a ferrite ring looped round both mains leads first or a ferrite sleeve clipped on.
Example https://uk.rs-online.com/web/p/ferrite-sleeves/1232479
Maybe try a ferrite ring looped round both mains leads first or a ferrite sleeve clipped on.
Example https://uk.rs-online.com/web/p/ferrite-sleeves/1232479
Lights shouldn't be flickering. Maybe you should have an electrician check out the building's wiring. Loose neutral wire connections are something that can be a known problem. Circuit breaker wire clamp screws can loosen, etc. In big buildings electricians check breaker panels with infrared cameras looking for evidence of unusual localized heating. Often tightening a connection is all it takes to fix the problem.
Otherwise, I would say the problem is with the laser printer. If it is flickering the lights and the AC power system is okay, then the printer is surely not okay.
Otherwise, I would say the problem is with the laser printer. If it is flickering the lights and the AC power system is okay, then the printer is surely not okay.
Hmm, I remember years ago owning Bryston 7B-SST monos, and every time I turned one on in my basement (my audio space), it would trip the breaker - One day I tried upstairs on entirely different circuit - no issues at all...only difference between two circuits was downstairs had an ARC FAULT Breaker, while upstairs circuit did not... I believe its CODE now...but always wondered...
It'll be the printer's fuser (heater) that is causing the issue, these things will easily draw 1Kw++
As other already noted above though - this loading should not be causing the lights to flicker! That's the big hint - to get your ac mains wiring checked, and fixed.
As other already noted above though - this loading should not be causing the lights to flicker! That's the big hint - to get your ac mains wiring checked, and fixed.
Definitely then.
Agree with having an Electrician checking house wiring, beyond Audio issues, for safety.
Unless wall wiring is made with hair thin wire (which is already bad), you may have, as suggested above, a poor contact (corrosion) "resistive spot" where all that voltage is dropping, and which will of course dissipate power and overheat.
One day you may see smoke coming out of an outlet or junction box 🙁
Absolute worst case ask Electrician to run a separate wire pair to a couple dedicated "High Load outlets" nearby and plug Laser Printer there.
WHAT can it be "eating"?
600W? 800W?
What brand and model is that printer?
Check specs or user manual.
Lasers have a long pencil type Quartz lamp inside the fuser cylinder, to melt Toner and stick it to paper.
For example this is a 500W lamp for a Lexmark Optra, I have seen 750W units for Samsung, 950W lamps are used in Photocopiers, way too much for home printer use.
So I don´t think you have a broken printer, they ARE power hungry, but poor Mains installation.
OK put my circuit checker and Hot / Neutral / Grounds are all good on all receptacles in entire basement. I then put in a Watt mater on that laser printer circuit and pulls 800va momentarily on print startup (printer fuser heating).
Crazy thing was it didn't drop out the Audio or dim lights this time, as I am going thru a different surge protector...will replace the previous surge protector to see if that was problem all along...
Crazy thing was it didn't drop out the Audio or dim lights this time, as I am going thru a different surge protector...will replace the previous surge protector to see if that was problem all along...
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That means nothing in this case, all it tells is that pins are properly wired , NOTHING about load bearing capability, only that pins are not reversed.
You could wire 1k resistor in series with every pin and it would display the same as before.
You were plugging everything into the same "surge protector"?
Then that´s your problem.
Most are VERY crude, just a varistor across mains out, and maybe a 2.5 or 5 ohm NTC surge protector in series, which of course will drop a lot of voltage until it warms up.
During the short toner fuser cycle it might even never fully warm up and even if it did, it would always start in the high resistance setting.
That´s its job!!
You know mains power is a 50 or 60 Hz sinewave, right?
If the laser printer engages when the sinewave happens to be around zero, the current will gradually build up along with the slope of the sinewave. Now, if the laser printer (or AC) happens to switch on while the sinewave is near the highest point, inrush current will be a large spike that makes the lights flicker.
That may not necessarily mean that the electric circuitry in the office is bad. It may also mean that the drivers inside the lighting fixtures are easily upset.
I can make the lights in my workspace flicker by switching on one of those Leister hot air guns that are probably triac controlled. As the triac switches on and off to regulate the temperature, so do the lights flicker in the same rythm. Better quality lights don't exhibit the behaviour.
I'm not convinced that momentary drop in mains voltage is the actual cause of your problems, even though it may seem to point in that direction. The PSU inside the DAC should be capable of bridging the milliseconds it takes for the dip to return to normal.
However, to verify this assumption, you could run an extension cord from another circuit to the laser printer while keeping the DAC connected to the current socket. If this solves the problem, yes, then I would agree that it's mains bourne (either voltage dip and/or EMC) and your solution should work. If the problem is 'merely' caused by mains bourne EMC, a mains filter might do the job.
If it's air bourne, then you'll have a hard time fixing the problem, because that's a whole other can of worms.
Good luck!
Edit: replacing the surge protector cured the fault, hmmm... what about the AC then?
The surge protector should protect against voltage spikes which make the voltage go much higher than nominal. Switching on a device with a high inrush current does the opposite, so you can understand why I'm a bit sceptic about the surge protector being the cause, but hey, if it cures the problem for good, it's good enough, right?
If the laser printer engages when the sinewave happens to be around zero, the current will gradually build up along with the slope of the sinewave. Now, if the laser printer (or AC) happens to switch on while the sinewave is near the highest point, inrush current will be a large spike that makes the lights flicker.
That may not necessarily mean that the electric circuitry in the office is bad. It may also mean that the drivers inside the lighting fixtures are easily upset.
I can make the lights in my workspace flicker by switching on one of those Leister hot air guns that are probably triac controlled. As the triac switches on and off to regulate the temperature, so do the lights flicker in the same rythm. Better quality lights don't exhibit the behaviour.
I'm not convinced that momentary drop in mains voltage is the actual cause of your problems, even though it may seem to point in that direction. The PSU inside the DAC should be capable of bridging the milliseconds it takes for the dip to return to normal.
However, to verify this assumption, you could run an extension cord from another circuit to the laser printer while keeping the DAC connected to the current socket. If this solves the problem, yes, then I would agree that it's mains bourne (either voltage dip and/or EMC) and your solution should work. If the problem is 'merely' caused by mains bourne EMC, a mains filter might do the job.
If it's air bourne, then you'll have a hard time fixing the problem, because that's a whole other can of worms.
Good luck!
Edit: replacing the surge protector cured the fault, hmmm... what about the AC then?
The surge protector should protect against voltage spikes which make the voltage go much higher than nominal. Switching on a device with a high inrush current does the opposite, so you can understand why I'm a bit sceptic about the surge protector being the cause, but hey, if it cures the problem for good, it's good enough, right?
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The surge protector has high internal resistance. That may be part of its filtering system, or it may be cheap, or it may be dying of corrosion.
Well, this is embarrassing, the new surge protector seems to have fixed the Lights dimming when printer starts, and a correct USB driver seems to have fixed the random Audio drop outs not related to printer too... well alright...