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OKI B4540 MFP – Multi Function Device Review


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Key Specifications

  • Review Price: £537.00

The idea of having all the main paper handling functions in one machine is a very convenient one. One device which can handle printing, copying, scanning and faxing is ideal for a small business or a workgroup within a larger organisation. In the case of OKI’s new B4540 MFP, SMS is added to the mix, as well as optional duplexing.

The B4540 MFP is an odd shape. There’s very little effort to integrate the two key components of the product, a flatbed scanner and a mono LED printer, into a homogenous unit. The scanner stands on two tall pillars which lift it well above the LED engine squatting between them. While you need access to the top of the LED unit to take off the printed pages, there’s still quite a bit of unused space.

Paper feeds from a 250-sheet tray which projects from the bottom of the front panel, with the option of a secondary, 500-sheet tray clipping in underneath, if you need it. The front panel of the LED engine folds forward to reveal a two-piece toner and drum unit, which is very simple to replace.

The control panel of the B4540 MFP is unusual in a number of respects. It starts off conventionally enough, with a two-line, 16-character status display and a ring of controls to navigate through its menu system. Stop and Go buttons skirt either side of this ring and to the right of these is a regular numeric pad for entering fax numbers.

On the left are pairs of buttons headed print, copy, scan, com and fax, with extra functions available in almost all categories. For example, the print button lets you cancel an existing print job and print a list of the device’s many numbered functions. The com button enables you to send an SMS text message to any phone or device that can receive one and to help with this, there’s a complete miniature QWERTY keypad at the right-hand end of the control panel.

It’s not much fun only having a user guide on CD, particularly when the set-up sheet is a single A3 page with very little help on the physical installation of the device. Installation mainly involves fitting trays, which isn’t difficult, but would be easier with printed instructions.

The lack of detail in the documentation extends to the electronic user guide, where quite major functions, like scanning to a PC, are covered in just one short paragraph. OKI claims the device can scan both sides of the paper in one job – but we couldn’t find out how to do it from any of the documentation.

There’s more software to install with the B4540 MFP than normal, as it includes a complete version of PaperPort 8SE, as well as custom-written fax and monitoring utilities from OKI. You can also control it over a network, as the machine is fully Ethernet-compatible straight out of the box.

Printing to the B4540 MFP is a speedy affair, though as usual not as speedy as the manufacturer believes. We saw about seven pages per minute printing straight text, against a claimed maximum speed of 20 pages per minute. Our pages are probably more complex, but also more real-world, than those used by some test laboratories. We time print runs with the test machine fully warmed up. If this machine is in stand-by, you need to add around 20 seconds warm-up time.

Copying our five-page text document from the scanner’s auto sheet-feeder was impressively quick, as the device printed at the same time as it was scanning, taking just 40 seconds to complete.

Print quality, as from previous OKI mono LED printers we have tested, is very good. Text is dense and crisp with even fine detail accurately reproduced. The machine’s standard resolution of 600dpi doesn’t detract from good character formation, with very few artefacts. Business graphics output is also reasonable, though some areas of colour originals produce banding when printed out in greyscales. Photographic output is clean, though some dark grey areas of our test print were reproduced black.

The standard toner cartridge can print 6,000, five per cent cover pages, while the optional high yield version can produce 12,000. The drum is claimed to handle 20,000 pages, so you can expect a good few months printing before you need to replace consumables.

Using the high yield toner cartridge gives a cost per page of 1.91p, which is a little on the high side for a mono device, but nothing too extortionate.


This is a well-designed device for anybody who needs all the key business functions in one, albeit ungainly, unit. However, it’s spoiled by poor documentation which focuses far too heavily on its fax functions. Unfortunately, some of its more esoteric functions may be overlooked.



Trusted Score

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Score in detail

  • Print Speed 8
  • Features 9
  • Value 7
  • Print Quality 9

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