Laser Printers

Brother DR-400: The Role of a Drum Unit on Laser Printer

What is a drum unit? Otherwise called the Photoconductive Unit (PCU) is a laser printer component containing the corona wire or separate charge roller and imaging drum. This consumable is purposely responsible for transferring toner to paper. The laser printer puts toner onto the photosensitive drum (roller) and then prints images and letters by setting toner to paper through heat and pressure. The drum unit can either be incorporated with the toner cartridges/s or a separate unit like the Brother DR-400.

How does it work? The Brother DR-400 drum unit for instance rotates to complete several tasks.

  1. A positive charge from the corona wire allows tiny laser beams to pick up or paint the image to the drum.
  2. As the positive charge paints the text, the negative charge it produces creates a reversed or negative background.
  3. The drum unit then attracts the toner through electrostatic. And as the paper passes through the PCU, the toner imprints on the paper with the image it has painted.
  4. The paper then passes through the fuser unit where the toner is melted and finally creates the final output.

When to replace the drum unit? A drum unit is a consumable; therefore, it depletes overtime. There are mainly two ways to know when the PCU needs replacing.

  1. An alert or message will appear on the LCD display indicating that the toner level is low along with a beeping sound.
  2. One of the most obvious indications that a drum unit needs replacing is when the printout quality begins to deteriorate or is defective.

Some users take no heed of the warning sign on the display and keep running the printer with an almost empty or a low toner level. This is not a good practice because it can damage the printer head and could eventually break the machine. It is fully understandable that the users would want to prolong the inevitable because a genuine drum unit is costly. Yet, there are cheaper but dependable options like the remanufactured Brother DR-400 to avoid damaging the printer.

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    July 14, 2017 at 1:32 pm

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    July 21, 2017 at 7:54 pm

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    July 27, 2017 at 1:17 am

    Your mode of describing all in this post is actually nice, every one be able to simply be aware of it, Thanks a lot.

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    September 4, 2019 at 6:27 am

    Thank you for this information. Glad i got some other hints on how do we know when a drum unit will be replaced. Also i have additional info’s aside from the given signs to replace the drum unit is the prints will get blur or having some black spots, poor print quality is characterized by faded text and images. I am sure the unit will be save long lasting printer.

  • Reply
    September 17, 2019 at 7:41 am

    This was very helpful thank you so much, I thought up until today that a drum was a larger capacity unit that came with the stated capacity of toner. Not just the above information but i also want to know the troubleshooting and maintenance schedule of drum unit, i am looking forward for more good info’s to it. Thanks

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    October 9, 2019 at 7:47 am

    Very nice read, without a drum unit, the toner powder in the cartridge cannot be transferred onto the page. The two parts work together to create a print! You can’t have one without the other and expect the printer to work properly.

  • Reply
    October 29, 2019 at 8:04 am

    Very well written, answers all of my questions as best one could. I wish life was not so complicated, though.

  • Reply
    December 4, 2019 at 6:43 am

    This is a very nice read, it’s nice to know more about device that you’re using instead of just using them.

  • Reply
    December 20, 2019 at 8:18 am

    To keep good print quality, the Brother machine detects the quality deterioration of the drum unit automatically. If the Brother machine displays “Replace drum” error message, you need to replace the drum unit.

  • Reply
    December 29, 2019 at 5:48 pm

    Great information i just knew that its a warn for us to continue printing even its almost empty because this is what i did to my printer and i still practice to over use it but this time i should stop, you saved me. thanks.

  • Reply
    January 7, 2020 at 2:29 pm

    I’ve never known this things before. Thanks for your blog, it really explains well how it works and also when to replace it. I honestly one of those abusive users but when I read your blog, I was worried bout the things I did. I wanna buy drum unit before it’s too late.

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    January 16, 2020 at 3:52 pm

    Useful blog! I”m fun of your blog because it gave me knowledge about the things I’ve disregarded before.

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    January 16, 2020 at 3:55 pm

    Useful blog! I have this feeling of being so addicted to learn more about printer’s parts and functionalities. Your blog really fits my interest.

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    January 28, 2020 at 2:38 pm

    I didn’t mind what’s the use of it before as long as it works well whenever I do the printing. Thanks for your blog! I was informed just today.

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    February 5, 2020 at 2:21 pm

    That was amazing! I thought I was watching television as I imagine things while reading this article.

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    February 13, 2020 at 2:49 pm

    I’ll keep it in mind. Thanks for sharing!

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    February 23, 2020 at 2:34 pm

    Thank you for sharing! Now I know the use of drum unit in a laser printer.

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    March 22, 2020 at 10:19 pm

    Time never wasted when I read your blog. Looking forward to more shared information.

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    March 24, 2020 at 10:13 pm

    Got it! Thank you for this fact it is worth sharing to others, I must tell my friends about this blog.

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    March 30, 2020 at 10:13 pm

    Just done reading it and will read other content too. I finally get some productive activity during this home quarantine life. I’m learning while at peace.

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    April 6, 2020 at 10:20 pm

    I ordered a remanufactured Brother DR-400 at amazon and it keeps my toner printer going well while at work.

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    April 13, 2020 at 8:45 pm

    Nobody informs me of this until I read your blog. Thanks a lot for unlocking my ignorance regarding this thing.

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    April 15, 2020 at 8:54 pm

    In my younger years, I never mind this thing but now I find it useful to know about it. Thanks for this article!

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    April 23, 2020 at 10:46 pm

    This article has given me a lot of information. Helpful one! I hope you continue making articles related to printers because I’ve done reading all and hoping for a new one.

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