Safety module for SSI absolute value encoders
The S-DIAS SSI 021 safety module, from SIGMATEK, is able to analyse two synchronous serial interface (SSI) absolute value encoders. Its two-channel configuration is said to ensure the safe collection and processing of position values in the SSI in accordance with SIL 3 or SIL CL 3 according to EN 62061 and PL e, Cat. 4 according to EN ISO 13849.
Connecting two SSI encoders to a common signal enables multiple sensors, such as distance measuring systems, to be read at the same time. This is a benefit for applications with synchronisation functions. The signal frequency can be set using software, so that the data transfer can be simply adapted to the cable lengths. The number of data bits can also be configured through the software to provide flexibility in regard to the resolution. With the SSI 021 safety module, safety functions for drift, speed, direction and ramping for example, can be implemented.
With the LASAL SAFETY Designer, users have a tool for programming and configuration. Logic connections and I/O configurations can be easily created. Predefined, certified standard function blocks (logic blocks, timers, counters, etc) and function blocks based on the PLCopen standard simplify Safety programming and maintenance.
Source: Control Engineering Europe - All Articles