TWO-HAND CONTROL PANELS
Application:
Two-hand control panels are non-separating protection devices. In general, they serve to ensure the machine operator's hands are located on the control panel when the control signal for a hazardous movement is issued. Two-hand control panels thus ascertain that intervention by the operator in dangerous moving processes is avoided when a machine or plant has been started.
The areas of application include presses for metal working, powder metallurgy, printing and paper processing machines, croppers and similar, as well as machinery in the rubber, plastic and chemical industries.
Two-hand control panels are the preferred protection devices for use in setting-up work and single-stroke operations for feed and removal processes.
Further information on the use of two-hand operation consoles and their evaluation is given in EN 574.
In order to achieve Category 0 to EN 60204-1, an additional signal evaluation circuit is needed. Safety monitoring modules for secure evaluation of signals from two-hand control panels and Emergency Stop devices are to be found in chapter xx.
Design and mode of operation:
Two-hand control panels are protection devices, which require the simultaneous use of both hands for their actuation. By virtue of their forced location, both hands are kept out of the area of danger. In order to start and continue the operation of a machine or plant which can be dangerous, the location of the hands is controlled as long as danger can continue to be present.
The two-hand control panels are mounted as standard with an Emergency Stop push button to EN ISO 13850 and two operating units. In addition, there are guard hoods over the operating elements, which prevent simple manipulation of the protection function using hands, elbows, stomach, hips, thighs or knees, for example.
EN 574 differentiates between various types of two-hand switching circuits with regard to their technical degree of control security. In this respect, the selection of the type depends on the evaluation and the risk assessment.
