Method for monitoring an output unit
AssigneeSiemens Aktiengellschaft
InventorsHartmut Schuetz, Andrea Ringler, Manfred Mueller, Johann Schinnerl
Life of this patent
Estimating the term…
Abstract
A method for monitoring the output function of an output unit (9). In particular, the output unit is a binary output unit of a safety-oriented programmable logic controller, which controls actuators (11) of an external technical process. The output function of the output unit (9) is monitored within a predetermined time interval by using bit patterns, which are produced by the external technical process, and by using bit patterns, which have not been transmitted by the output unit (9) to the actuators (11) of the external technical process. Therein, the number of output test bit patterns is reduced to a necessary minimum.
Claims5
A method for monitoring an output function of an output unit, wherein the output unit controls actuators of an external technical process, wherein the output function of the output unit is checked within a predetermined time interval by means of only such bit patterns that have not been transmitted, within the predetermined time interval, by the output unit to the actuators of the external technical process, and wherein second bit patterns that are transmitted by the output unit to the actuators of the external technical process are balanced.
A method for monitoring an output function of an output unit, comprising:
- commencing a predetermined time interval;
- and
- executing an external technical process by
- controlling actuators with operational bit patterns during the time interval;
- comparing the operational bit patterns with test bit patterns;
- and
- testing the output function by checking with only those test bit patterns that do not coincide with the operational bit patterns.
Dependencies are inferred from the claim text.