Sick has developed a digital motor feedback interface that allows encoder signals to be sent via two wires integrated into motor cables up to 100m long. As well as minimising cabling between motors and frequency converters, the Hiperface DSL interface will save space and costs by avoiding the need for feedback connector plugs on motors.

The interface complies with RS-485 and supports 9.2Mbd transmission speeds. Data transmission takes place synchronously with the control cycle, which can be as short as 12.15µs. The system avoids the need for analogue components on the control side.

The first products to use the new interface are a pair of absolute encoders in a compact, robust 36 housing. The EKS/EKM36 encoders (above) offer a resolution of up to 20 bits per turn, as well as up to 4,096 rotations. Motor data can be stored in electronic “labels” and programming of the position value is said to simplify commissioning.

For more news from the SPS/IPC/Drives Show, see our detailed report.