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Bob Larter Bob Larter is offline
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Default UPS: "Do not connect laser printer..."

notme wrote:
What is it about laser printers that causes UPS manufacturers to recommend
they not be powered by a "stepped approximation to sine" UPS? It's a SMSP,
isn't it? What makes it special such that it needs sine-only? No such caution
re. computers, etc...


The big difference is that lasers usually have a mains powered quartz
lamp inside the fuser assembly to cook the toner onto the paper. My
guess would be that the lamp puts a huge current spike on the mains each
time it powers up, which is every minute or so. If so, that spike might
overload the UPS.

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