Re: OT: surge protectors

All I can say is that I have dealt with APC directly on the subject, and APC
recommends NOT attaching laser printers to their UPS's, because a laser printer
draws a serious amount of current to warm up its laser every time it comes out
of standby mode. I have also dealt with the phenomenon first-hand, so I have a
bit of practical experience, if not deep grounding in the underlying whys and
wherefores. The amount of current can be enough, even with a UPS having a
sufficiently high kva rating to cover all devices, to cause computers to reboot
when both laser printer and computer are powered by the same UPS operating in
battery mode with zero input voltage on the electrical line.

Your explanation about dirty electricity emanating from a UPS makes sense. I
have no problem with it. Perhaps I misinterpreted what you wrote, or maybe I
did not see sufficient caveats accompanying it.

Still, for two reasons, I do not recommend attaching a laser printer to a UPS.
First is the aforementioned effect of a surge in drawing power by the laser
printer. The second is my perhaps narrow-minded view that printing is not
typically a critical operation when power is lost and equipment is running 100%
on UPS-supplied power. What is critical for most of us when power is lost is
to finish whatever transaction is in process, saving data on the hard drive,
finishing up whatever is being done on the internet and so forth. And then
powering down to wait for electricity to be restored by the electric company.

If anyone wants to do otherwise, that is fine by me... Ben Myers

On Mon, 25 Feb 2008 23:30:11 -0800 (PST), w_tom <w_tom1@xxxxxxx> wrote:

On Feb 25, 9:07 am, Ben Myers <ben_myers_spam_me_...@xxxxxxxxxxx>
wrote:
Nearly all responsible manufacturers of laser printers (Brother excluded,
because they apparently are not responsible and are newcomers to the laser
printer game) state strongly that laser printers are NOT to be plugged into a
UPS. They must know what they are talking about. To make a generalized
statement that it is OK to do so is not the most responsible thing to do.

Please read what was posted; please do not read with personal bias.
If Ben Myers grasped the 'reasons why', then he would have never
posted erroneously on 25 Feb.

A UPS will power a laser printer just fine when not in battery
backup mode. When that UPS switches to battery backup mode, then its
'dirty' electricity may be harmful to a laser printer. The exact
quote that Ben Myer had to ignore. w_tom posted:
Laser printer power consumption is a problem when the
typical UPS is in battery backup mode. Those above
listed problems ('dirty' electricity) occur when UPS is in
battery backup

Did I "make a generalized statement that it is OK to do so"? No.
Obviously not. So obviously not that Ben Meyers had to read
selectively; had to ignore 'reasons why'.

Ben, do you know why a printer manufacturer recommends not powering
that printer with a UPS? If not, then you have insufficient
knowledge. Those who demand the 'whys' also saw through myths of
Saddam's WMDs. You don't know something if you don't also know
*why*. My post included 'reasons why'. Ben had ignore basic
technology - the 'reasons why' - to post on 25 Feb. Same mistake was
made by those who also believed Saddam had WMDs. We are supposed to
learn from history. Unfortunately Ben Myers had to ignore 'reasons
why' to misrepresent what w_tom posted.

Important point in that post: a typical 'computer grade' UPS outputs
electricity so 'dirty' in battery backup mode as to be harmful even to
laser printers.

How to make a printer that can withstand a UPS output? Connect a
power supply between that UPS and all printer parts. After all,
cleaning (regulating) is what a power supply does. Why is that
'dirty' electricity from a UPS not harmful to computers? Everything
in a computer is powered via a power supply. 'Reasons why' are
critical in understanding these warnings. Ben Myers had to ignore
'reasons why' to post erroneously on 25 Feb.

Ben: 1) You misread what I posted. 2) Then you completely ignored
the 'reasons why'. You made two mistakes to reply with criticism. I
hope that was only extreme carelessness.
.

Relevant Pages

  • Re: Fluctuating Electrical current
    ... lamp and a laser printer. ... on the printer it trips my battery backup power strip for a split ... the hall which is only running an alarm clock and a lamp. ... In some office buildings, with system ups ...
    (alt.home.repair)
  • Re: OT: surge protectors
    ... The maximum rated wattage of a laser printer is ... pretty high, too, often exceeding the capacity of a typical UPS. ... then dirty 'computer grade' electricity is not harmful. ... Do not power 'at risk' appliances such as a laser printer via UPS. ...
    (alt.sys.pc-clone.dell)
  • Re: Laser printer draws current in a spike, what for?
    ... >> makes the lights flicker as well as causing a UPS on the same circuit ... In my case, I simply moved it off of the UPS, ... A laser printer sold in Europe must conform to EN 61000-3-2 and -3. ... The bad news is that everything is prohibited. ...
    (sci.electronics.design)
  • Re: Laser printer draws current in a spike, what for?
    ... >> makes the lights flicker as well as causing a UPS on the same circuit ... In my case, I simply moved it off of the UPS, ... A laser printer sold in Europe must conform to EN 61000-3-2 and -3. ... The bad news is that everything is prohibited. ...
    (sci.electronics.basics)
  • Re: UPS
    ... You can buy a portable generator system, ... UPS will keep the computers running for a few minutes while ... Printers can be allowed to power off and the ... be asked to run a laser printer because even in standby, ...
    (microsoft.public.windowsxp.hardware)