In addition, they must in the event of failure of a component sure turn off. Most manufacturers of radio remote control using digital technology. Because only it offers unlimited possibilities to encrypt the transmitted and received signals. Thus each of the radio remote control is a unique piece, which can be controlled by any other device. This will reduce the command data such as, for example, load”prior to their transfer to the recipient so encrypted, which can clearly identify whether they have been changed by any transmission errors on the path. By a multi-digit numeric address, the receiver detects that the incoming data for it are determined. This address is added to the so-called telegram that also contains the launch information, the actual transmission data, the safety information and the stop information.
Only this self testing transfer mechanism can ensure that the receiver detects the transmitted telegram as a reliable and accurate. The safety function is then, if the receiver normally continuously no longer receives signal broadcast from the transmitter. This can happen because you might encounter a transmitter failure due to a discharged battery, or transmitter and receiver are too far apart. In these cases, the crane is switched off. The system at many manufacturers automatically then goes into the safe state, when the recipient has received no signal for more than 0.5 seconds. More security features provide protection against unintentional and unexpected recovery, because the receiver suddenly regains a signal: responsible for this case so-called zero position monitoring of the recipient ensures that the crane only restarts after renewed activation of a control function. This zero position monitoring also exists in the transmitter. There, she ensures that not immediately and for the operator of surprising a function is running, if, for example, already when the transmitter is switched on depends on a button. Should now despite all precautions once an error occur, it is ensured that he can cause no harm to humans and machines: ensures the passive emergency stop circuit as so-called parent instance: an error occurs, for example, a relay sticking, so the crane is switched off but reliably and instantaneously.