In the case where two hand control is used, both Safeballs i.e. all four pushbuttons have to be activated within 0.5 seconds. If one or more pushbuttons are released a stop signal is given to the machine. In order to provide the highest level of safety the Safeball designs provides the operator with a dual switching function and short‑circuit supervision in each hand. A Two hand control can be used when it is necessary to ensure that the operator is outside and must be prevented from reaching into the hazardous area. If the operator decides, after the start signal has been given to the machine, to make an 'after‑grasp' i.e. try to adjust the part that has been placed into the machine, then a dual stop signal is given to the machine.
