User Manual

3SU12 compact units
6.1 Overview
SIRIUS ACT 3SU1 pushbuttons and signaling devices
System Manual, 02/2015, A5E03457306020A/RS-AB/002
125
6.1.2
Sensor switches
Sensor switches are capacitive sensors that are actuated when the sensor surface is
touched (without application of force or pressure).
Sensor switches are used to operate machines or as door opening switches and stop call
buttons. Thanks to the water-sealed electronic circuitry and rugged enclosure materials used
in their construction, these capacitive and fully electronic sensors are extremely durable.
Since sensor switches have no moving mechanical parts, they are maintenance-free. Two
integrated status display LEDs provide the user with visual feedback.
Sensor switches
Typical diagram
Material
Article number
Plastic / Plastic 3SU1200-1SK10-2SA0
(http://mall.industry.siemens.com/mall/en/en/Catalog/Product
s/10221502)
Application example
When the sensor switches are combined with the appropriate Siemens DIN EN 574-
compliant evaluation devices with type III C certificate (devices from the SIRIUS 3SK1
Advanced safety relay range or devices from the 3RK3 Modular Safety System (MSS)), they
can be deployed as a safety relay, for example, in two-hand control applications. A two-hand
control device requires simultaneous actuation with both hands in order to start up a
machine and to keep it in operation in a potentially risky situation. The two-hand control
device must be located outside the hazard zone (and the hazard zone must be clearly
visible) in order to prevent the operator from entering the zone before the machine has
reached a complete standstill.
The control command is sent by actuating both pushbuttons simultaneously within 0.5 s.
The following properties must be provided for mobile two-hand control devices:
Stability
The safety distance must be maintained between the control actuating devices and the
hazard zone
In the case of adjustable control actuating devices, a latch must be available
The sensor switch provides effective shock protection and the operating surface is easy to
clean (type of protection IP69)