🚀 go-pugleaf

> But what's
> supposed to happen if we use it more heavily than its allotted 3000/month?  
> I.e., what does "duty cycle" measure?

Not bloody much.  We have an Imagen 2308 (formerly 8/300) which is
based on the Canon LBP-CX engine (same as, I believe, a Laserwriter).
We received it in January of 1985 and have averaged between 4000 and
6000 pages per month on it ever since.  That's well over 100000 pages
in two years---and that's a pessimistic estimate.

Have we had problems with it?  Of course!  But 80% of the problems were
with Imagen's processor box, not with the print engine (we've replaced
the power supply and just about every board in the processor).  Aside
from replacing the silly plastic "paper separator" every few months,
only two things went wrong with the print engine.  First, we had to
replace the fuser roller assembly---the very last set of rollers in the
paper path.  This assembly is responsible for heating and "fusing" the
toner to the paper.  The assembly is not designed to last more than, I
think, about 50000 pages.  Sooner or later, you have to replace them.
Second, the clutch mechanism that drives the paper pickup roller (the
roller that actually picks up paper out of the paper tray) slowly gave
out over the course of several months.  The result was a groaning sound
accompanied with a noticeable temporary decrease in the speed of the
paper path.  In other words:  the paper would actually slow down for a
few seconds while the mechanical engine would groan and moan.  For some
reason, the image processor software 2.2 was able to cope with this
slow-down, although Imagen technical support was very surprised by that
statement (and probably didn't believe it).  But the new software/
hardware, 3.3, was not.  The image would come out squashed at the
bottom of the page.  So, we finally had to say goodbye to the 2 year
old print engine and replace it with a refurbished one.

I think that duty cycle is an estimate of how hard you can push your
print engine and still have it perform optimally.  But the estimate is
purposefully a pessimistic one.  We pushed our engine well past that
limit, and it still lasted for two years.  We could have had that
specific engine repaired and refurbished and returned to us, but that
would have taken longer than just having it replaced with an already
refurbished one.  So our two year old engine is actually still in
commission---it was refurbished and sold to another customer.  We just
don't know where it is.

			William LeFebvre
			Department of Computer Science
			Rice University
			<phil@Rice.edu>