Running a printer on a UPS

[tyler.s._apc]

This was originally posted on APC forums on 9/4/2013

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I have a customer who wants to run a desktop PC, monitor and "small printer" on a UPS for 30 minutes.

I confirmed that the printer is a necessity, and needs to be able to run during an outage (rules-out running it through a surge-only outlet).  Is there a Back-UPS and/or Smart-UPS capable of this?  In the past, I've always recommended the printer NOT be used, and it's usually not an issue.

Thanks!

Tyler

[BillP · Accepted solution]

This reply was originally posted by Angela on APC forums on 9/4/2013

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Is it a laser printer? We'd need to know the power consumption of the devices too. My thought is if you HAD to use a laser printer, you need to size the UPS accordingly to handle in-rush from the printer warm up.

[tyler.s._apc]

This was originally posted on APC forums on 9/4/2013

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I knew you'd be able to help, Angela! 🙂

I'm waiting to hear back from the customer on the model of the printer. If it's not a laser printer, are there any other necessary requirements I should look out for? Is stepped approximation safe or is a pure sine wave required?  According to some Google perusing, it looks like a lot of basic ink jet printers only pull 15-30 watts while printing.  Obviously, laser printers have huge in-rush currents to worry about, but that doesn't seem to be the case with ink jets. I've heard that printers in general should not be used with UPS units. Any truth to that, or are laser printers just giving printers in general a bad reputation?? 🙂

Thanks!

[BillP · Accepted solution]

This reply was originally posted by Angela on APC forums on 9/5/2013

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Hi Tyler,

No problem. Here is some info one of our UPS support folks after I asked for some feedback to make sure I didn't miss anything:

The issue is only with laser printers. Ink Jets are no problem as long as the load is sized for their draw while printing (which is usually 15-30 watts like the you said.) With laser printers, the issue is the fuser assembly. It is essentially a heating element that fuses the powdered toner to the paper. The sine wave isn't actually a problem but it's initial inrush which can be huge. You can usually get away with a Smart-UPS 1500 VA for smaller desktop lasers, although anything more commercial sized might be better off with a 2200. I would probably direct the user to an SMX unit just because it has a higher watt rating than the SMC/SMT. Most customers just save the print job in their queue and reprint when power returns.