DN over the years has produced and converted a large variety of materials testing devices. They can be divided into the following categories;
Force is generated by a hydraulic ram, driven by hydraulic pressure from a pump.
Earlier versions interfaced with the computer via the Moller board, the electronics being first contained within a desk or cabinet and later in the "cube" electronic console. A ribbon cable was use to connect the Moller board to the electronics. Not many such devices survive. They require Issue 6 software.
Later versions use the Compact Controller drive, interfacing with the machine via a thick round cable. They use Issue 7 or Windows software.
Later still, a few USB machines were delivered. They require Windows software.
The sample is located between a fixed and a moving crosshead, the moving crosshead being driven by a couple of lead screws.
In earlier versions there was an electronic box connected to a Moller board in the computer, again by a ribbon cable. The box in turn is connected to the frame. Issue 6 software is required.
Later versions use the Low Cost Board in the computer connecting to the frame by a thick round cable. Issue 6 or Issue 7 software may be used.
There were a few specialist test frames produced - all conversions of machines by other manufacturers. There is a single precision lead screw driven by a powerful motor. They look like hydraulic machines, but of course there is no oil pump. They are controlled by the Compact Controller and require Issue 7 software.