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ABB Low Voltage Industrial Products 0312
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Sensors and switches
Why you should use sensors and switches
- to supervise doors and hatches around dangerous machines!
Assurance that a machine stops when a door or a hatch is opened can be solved
by using different types of switches and sensors which are monitored with a safety
relay or a safety PLC. Switches and sensors are available both as non-contact
(dynamic or magnetic) and various types of interlocking devices. Interlocking
devices can be used when it is required, via a signal, to lock a gate during proc-
esses that cannot be stopped during certain operations. They are also used with
machines that have a long stopping time to prevent someone from entering before
the machine has stopped.
- to manage the safety in harsh environments!
Non-contact dynamic sensors have a long lifetime because they are not physically
mechanically operated. They also endure very harsh environments, e.g. cold, heat,
high-pressure wash-down which is important in the food industry for example.
Because the sensors are small, they are very easy to position and can even be
completely concealed in doors and hatches.
- to ensure that a position is reached!
The sensor monitors that the robot is standing still in a monitored position when
someone enters the robot´s working area. The robot is then only stopped by the
program. If the robot leaves the position the power will be cut directly. This is used
when the robot does not stop safely without restarting problems.