when it starts up - like when it’s restarting, or waking up to start a print job. Several lights blink, and the computer’s UPS clicks on and off. It’s an office-sized laser printer (well, all-in-one).
The printer is not on an UPS, just an old surge protector strip. Would putting it on its own UPS solve the problem? or a better surge protector?
Either your UPS is shot or there’s something wrong with the printer. Or maybe the draw is too much for the UPS. Check the ratings.
ETA: Wait a minute. The printer is not on an UPS, but the computer’s UPS blinks? You’ve got a problem with your power feed.
It’s normal.
It’s called “flicker” and it’s regulated in the EU, but not in the US. The printer draws a lot of power when it first turns on its fuser.
ETA: some technical info here.
That’s one hell of a draw if you call that normal. No circuit or printer I’ve ever seen or would accept does that. MZ, are you sure your circuits aren’t overloaded?
My basement lights are on the same circuit as my clothes washer, and when it’s agitating the lights flicker a little bit.
beowulff is quite correct in that the printer’s fuser is the culprit. copiers and laser printers print by depositing toner (a powdered plastic) onto paper, and the job of the fuser is to literally melt the toner onto the paper. This means the fuser has to get real hot, real fast and draws enough power to do so.
Enough to cause an UPS on another circuit to kick in? You’ve got a power problem.
Modern printers have circuits that prevent fusers from turning on at the same time as everything else to avoid this. Heck, even my 1968 audio power amp had that kind of circuit with a delayed start. It’s not a new concept.
My laser printer turns on with no flicker in the overhead lights or anything else, so it isn’t a requirement, and the computer table and printer are on the same circuit.
You are seriously over-reacting.
First of all, the OP never said that the UPS was on a different circuit.
Secondly, the statement
is gibberish. The fuser alone is enough to cause flicker.
Thirdly, I have a laser printer that does exactly the same thing (causes flicker, and the UPS to activate), and my wiring is just fine.
No? What does this mean:
If the computer is on a UPS and the printer is not, there’s a different circuit fork here, even if the wall outlet is the same. The UPS should isolate whatever it drives from whatever it doesn’t. The only reason is should kick in is that the current fed to it is insufficient.
And I have owned and serviced dozens of laser and other printers (hundreds, even), and the fuser typically kicks in independently from the rest of the box. Obviously, YMMV.
i agree it is a large current draw when it starts, causes a voltage sag.
UPSs don’t isolate anything. They are pass-through until activated.
The UPS is doing exactly what it’s supposed to do - detecting a low input voltage situation, and switching to battery backup. When the printer powers up, it causes voltage sag, and the UPS reacts. You need to consider the voltage drop on the wire run from the breaker panel to the printer. It’s likely that putting the printer on it’s own breaker will minimize or eliminate the flicker, because the voltage drop will be confined to the wire run supplying the printer alone.
only if it’s an online/double-converting UPS. I don’t know that many consumer-grade units are.
They exist both ways and I’ve used both kinds.
To clarify: it is on the same circuit (as in, if the circuit breaker trips, the whole room plus part of the hallway goes dark) but it is not plugged into the UPS that the computer is on - in fact, they’re on opposite walls in the same room.
The behavior happens when I’m booting it up, or when I print - I just printed a page and it flickered when the thing first got the signal (including causing the UPS to blip), and the lights flickered then and again a minute later after the page was done.
The electrical wiring in this house is imperfect - our ground fault switches have occasionally tripped at random.
I am hoping that putting it on its own UPS would isolate the power draw from the house current - i.e. it would draw from what the UPS has stored.
This is a Brother laser printer and apparently this is a known issue (one I hadn’t stumbled across before I bought it).
Well, since they’re on the same circuit, the printer grabbing all the juice would make the UPS think it had lost power, hence the clicking.
I haven’t heard those terms before - can you explain?
if the UPS is offline or line-interactive, under normal conditions the power from the wall socket goes directly to the devices (computer, etc.) When power goes out, the UPS rapidly switches on the battery-backed inverter to keep the devices powered.
with an online/double-conversion UPS, under normal conditions power from the wall does not go directly to the devices plugged into the UPS. Instead, it goes to the DC power supply feeding the batteries, in parallel with the inverter. so when power goes out, there’s no switching needed. the AC power from the wall disappears, along with the DC power supply, but the batteries just maintain the feed to the inverter.
Answering my own question:
Thanks - that meshes with what Wikipedia says but is rather more comprehensible!
I looked around Amazon and it’s hard to tell, from the description, what type the various units are. I tried including “online” or “on-line” in the search but Amazon’s search tool always returns such irrelevant crap.
Adding: I tried including “double conversion” and got a handful of very expensive (as in, more than the printer) units. Not sure it’s worth it for us, as long as the printer isn’t actively endangering the household!!
I haven’t had much experience in this area, but going on what happened when I tried to use our UPS as a free outlet to plug our vacuum cleaner into, putting the printer on a UPS may not help. When I tried plugging the vacuum cleaner into the UPS, it went into emergency mode and shut everything off. UPSes don’t seem to like sudden big power draws, which is what happens when the fuser turns on.
I guess what I am saying is try it out using your existing UPS before you invest in another one for the printer.
ETA: Our old laser printer used to make the lights flicker when the fuser turned on, but didn’t affect the UPSes. I assume they were on a separate circuit. Our newer laser printer doesn’t cause the lights to flicker.
I think any UPS that can handle a color laser (I’m assuming) is probably going to cost more than half of what the printer cost.
I just looked at the specs for a few office models on NewEgg. While the normal amount of wattage these machines draw while printing is in the 500-700 watt range, they can peak at over 1000watts. That means you’d need a UPS rated at about 1600VA - since a rough rule of thumb is that the rated wattage of a UPS is about 60-65% of the VA number.
I really don’t think it’s anything to worry about. I have the same issue with my laser printer and it’s on a completely different circuit. I don’t think the lights blink much, but the UPS’s that the computers are plugged into sound like those chattering false teeth gags. My house was built in the 60’s but it has a 100 amp breaker box and everything is in good shape. The worst that’s happened is that a few times I’ve put too much on one circuit and I’ve had to reset the breaker switch.
There is absolutely no reason to put the printer on a UPS!
(Unless you want to print during power failures)
It is irresponsible to cure symptoms. Fix the problem. Your wires are more than sufficient to provide any printer with power and not dim lights. You apparently have a loose wire or some other more dangerous defect. Fix the problem. Never cure symptoms. Find the defect.
In most cases, the problem is only a problem for the printer and nearby UPS. In some rare cases, the problem is a major human safety threat. Fix the problem.
A UPS is only temporary and ‘dirty’ power during blackouts. ‘Dirty’ because all electronics are quite happy with dirty power. But that same ‘dirty’ power can be harmful to power strip protectors and small electric motors. Just another reason why a UPS is not used on some printers.