This is a common point of confusion for a lot of people. Quite often we will get customers purchasing a drum unit, thinking that is ‘drum of toner’, or a super high capacity cartridge. Or we will get people phoning up confused, as they have pulled both the drum unit AND the toner cartridge out of the printer and are trying to replace it with just the toner.
So what is the difference?!
The drum unit is the part inside the printer that transfers the toner onto the paper. The way it works is it uses an electro-static charge to attract the toner and put it on a photo-sensitive roller inside the drum unit; the toner is then transferred onto the paper using heat and pressure.
It is important to note that the drum unit DOES NOT include the toner, which is purchased separately in a toner cartridge.
The life expectancy of the drum unit can vary dramatically depending on the model and manufacturer, but commonly they will last for around 4-5 toner cartridges.
The toner cartridge is that part that actually contains the toner! Toner is a fine powder that is a mixture of plastic particles, carbon, and colouring agents. Cartridge options can vary, again depending on the model, but you can usually find standard yield or high yield cartridges, and generic (compatible) or genuine options.
In a lot of cases the toner cartridge and the drum will be connected inside the printer, and will come out as one unit. It is very important to remember this, and to check your user manual for instructions to ensure that you don’t damage the drum when replacing a cartridge!