02.05.2024

Tradition meets state-of-the-art technology

Absolute rotary encoder with bit-parallel interface

Absolute rotary encoder with bit-parallel interface

We have now become accustomed to high-tech sensors such as rotary encoders having an industrial Ethernet connection and transmitting their complex actual values (position, speed, other status information) to a (now mostly PC-based) controller via a standardized bus protocol. The times when a separate line was used for each bit of the absolute position value seem to be forgotten. But sometimes this is exactly what is required. The first applications that come to mind are those in which new encoders have to be connected to existing control technology that only has a bit-parallel interface and no bus or even Industrial Ethernet connection.

However, the rotary encoders with parallel interface from TR Electronic can do much more. In addition to the bits for the position, the encoder is also able to generate many different special signals such as direction of rotation, standstill monitors, virtual limit switches and thus replaces additional evaluation electronics for direct on-site evaluation.

Like all encoders of the current Generation 2, various shaft shapes and diameters are also available in the standard modular system when using the parallel interface. Rotary encoders in size 58 mm can be equipped with solid shafts up to 12 mm in diameter, with blind hole and continuous hollow shafts up to 15 mm.
The C_H802 and C_H1102 designs are available for larger shaft diameters. Their through hollow shafts can accommodate machine shafts up to 25 mm (for 802) or 50 mm (for 1102).

Generation 2 of the TR absolute encoders also adapts to customer requirements in other parameters: Fully magnetic scanning with up to 13 bits within the revolutions is available, as is high-resolution optical scanning with 18 bits within the revolution. In addition, 4096 revolutions are genuinely scanned, without the need for a battery or electronic counter - the reliably determined position value is available immediately after switching on, even if the system has been de-energized.

As is usual with the current generation of TR encoders, an additional actual value output can also be combined with the parallel interface. You can choose between SSI and incremental interface. The combination of absolute SSI interface (which itself has been established on the market for many years) and parallel interface offers the best of both worlds: The entire measuring range of true absolute multiturn sensing is transmitted serially without being limited by the number of conductors and additional signals such as a direction of rotation, standstill or speed monitor function are generated and output directly in the encoder. The configuration (resolution, which signal on which output channel...) is carried out using TR's own TRWinprog software, which is used to address the integrated 2-wire programming interface. On the PC side, a USB converter ensures that the programming tool remains electrically isolated from the system and that longer cable lengths between the connection point and the encoder are also possible.

The encoders with parallel interface are usually connected to the controller via multi-pin plug connectors, e.g. SubD. As standard, the cable between the encoder and connector is 0.5 m long, but special length requirements can be accommodated.

And if that is too many options - our colleagues in the various technical offices and at TR support partners worldwide will help you to define exactly the right encoder for the application and put it together from the standard modular system.

Generation 2 encoder with parallel interface in our product selector

Press article including photograph