GAMMA SYSTEM GP02/E, Use And Maintenance Manual

Page: 18 / 35

Use and Maintenance Manual – Pressure-sensitive bumpers type GSBPS 18/35
7 SELECTING THE BUMPER WHICH BEST SUITS YOUR REQUIREMENTS
In order to make the best choice for your requirements, you should keep into account several important
factors, such as :

The appropriate performance level according to UNI EN ISO 13849-1 Standard and in compliance with
the risk assessment of machinery or requirements demanded by possible products Standards.

Hazardous speed: It is the speed at which the hazardous surface moves. Usually, there is a stationary
surface and a moving one. Maximum possible speed should be considered as hazardous speed. If both
surfaces are moving, then special care should be taken.

Stopping travel of hazardous parts: It is the distance travelled by the hazardous surfaces after a stop
signal has been given to the machine control system by the output signal commutation device. This
travel distance depends on the hazardous speed, on the response time of the machine control system
and on the efficiency of the machine braking system. This travel can be calculated and/or measured. A
suitable safety factor should be used, where appropriate, to keep into account the brake wearing and
measurement tolerances.

Facility to use a set of sensors;

Elimination of dead zones;

Frequency of operating cycles;

Correct operation of the output signal switching device;

Temperature and humidity outside the defined range;

Radiant heat;

Sudden change in temperature and humidity;

Effects deriving from chemical substances;

Effects deriving from foreign bodies (scraps, dust and sand);

Additional cover for the sensor;

Stresses due to vibrations, shocks, etc…

EMC (Electromagnetic compatibility)

Supply voltage fluctuation outside the range specified by the Standards (EN 60204);

Sensitivity level can differ from the requirements of this Standard;

Need for a reset and position of the reset push-button;

Fastening of the sensor;

Change of performance over the time;

Indirect influence such as floor surfaces
;

Recovery time of sensor after deformation: In some applications, the time between subsequent
actuations of the sensor is less than the sensor recovery time. In this case, you should select a sensor
capable of recovering normal operation status within the available time.

Interfacing to the machine control system.