Every machine needs to have a large, red and easily accessible emergency stop button – but what if the operator is some distance away, or cannot reach it, when things go wrong? The answer is a wireless remote control. And while wireless can never be totally immune to interference or blocked signal, the measures taken in the Esalan wireless system from Schmersal make it about as reliable as is practicable.
The hand-held units come in various versions, with up to four movement control buttons, plus a prominent stop button. The units are operated either in the 433 MHz or 869 MHz band, switching between the two bands, if necessary. The system has a 200ms response time and a fault tolerance of 7, so the system sends a signal every 25ms. This means that the system reacts only when seven messages are missing or are transmitted damaged.
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