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Laser printers: The imaging drums have a chip on them which counts how many pages they have processed, and will refuse to work after a certain number of pages e
by 72deluxe 10y ago
Laser printers: The imaging drums have a chip on them which counts how many pages they have processed, and will refuse to work after a certain number of pages even if the drum itself is fine. They do this to stop potential damage to the drum.
You can buy cheap chips to put into the printer if you want to risk it - search for "drum reset refill chip".
- Yxven 10y agoIs damaging the drum dangerous, or is it a profit scheme?
- bonzini 10y agoThat's not to stop potential damage to the drum. It's because on average the drum starts showing damage around 30.000 pages (a damaged drum it leaves lighter or darker bands on the paper, same as on old badly-maintained photocopiers). But because _sometimes_ it starts shows damage earlier, and they don't want you to confuse a damaged drum and an empty toner cartridge, they just force you to change it around 20.000 pages. The drum reset refill chip is not even a chip, it's a 56 ohm resistor that acts like a fuse. The drum has two resistors in parallel, one with very low resistance and one that's like 200 000 ohm. If the printer sees a high current when you turn on the printer, the firmware thinks it's a new drum and resets the page counter. After a short while the 100 ohm resistor burns (quite literally), and from that point on the firmware will only see a low current when you turn on the printer, and it will not reset the page counter. So the drum reset refill chip lets you connect the two pads where the printer applies the current with a resistor like the one on a new drum. You can buy a 56 ohm resistor yourself to achieve the same effect. It's literally a resistor and some plastic, only usable once, and they sell it to you for $10, which makes it much more of a scam than anything printer manufacturers do.
- 72deluxe 10y agoThanks for the info!