I took apart an old printer and found two components that look like relays.

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But they have no markings of any kind, save for a small sticker each that I think may be serial numbers.

They are 4335xit3 and 5345xft4.

I would love to find some data sheets to know what they can do, but I don't know how to identify them without markings.

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    \$\begingroup\$ fyi: General discussion about merit of salvaging parts from consumer goods. \$\endgroup\$ – Nick Alexeev Jan 9 '17 at 3:57
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    \$\begingroup\$ While theoretically possible, relays are not common in printers - generally the electro-mechanical components have more to do with the fact the a printer is a type of enclosed robot. If you want to understand what these do, you should consider where they were in the physical assembly. A mechanical actuator that closed a circuit as well as doing something physical would be more likely to be found than a pure relay in the sense of a mechanical actuator that had not purpose other than to close a circuit. It would also be good to state the type of printer. \$\endgroup\$ – Chris Stratton Jan 9 '17 at 4:05

That is the flyback transformer used to generate the high voltage charge in a laser printer.

The comparable circuits in a CRT-based television can remain hazardous for substantial time after power is removed, unless the tube capacitance is carefully drained by someone knowledgeable in the appropriate procedure.

I can't tell you off the top of my head what associated capacitance would be found in a laser printer or what voltage it would charge to, but until you know for certain, you probably don't want to be working on or disassembling the machine - if something is still charged the results could range from surprising through painful to truly hazardous, even when unplugged from the wall. Such hazards are not necessarily confined to televisions or large objects - in childhood I got a rather unique burn from discharging the capacitor in a small camera flash through my finger.

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  • \$\begingroup\$ Hmm, OK. I was hoping to recycle and save some money, but I see that it's probably better to just buy from a reputable source with the data sheets. \$\endgroup\$ – AndyD273 Jan 9 '17 at 4:23
  • \$\begingroup\$ Even before lack of data (which can often be overcome with experience), there's the eternal problem of needing what you find or finding what you need. \$\endgroup\$ – Chris Stratton Jan 9 '17 at 4:27
  • \$\begingroup\$ I've seen an almost identical device in a laser printer, it was providing charge to the toner drum so it's most definitely a HV flyback (3-5kV probably) \$\endgroup\$ – Sam Jan 9 '17 at 22:35

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