Safety Light Curtain
79
5.2.5 Blanking
Blanking is required for applications including objects which continuously protrude into the safety field, thus
interrupting specific light beams of the ESPE. In order to maintain a high availability of the application even
under these conditions, the interrupted beams are excluded from the evaluation during “blanking”. A safety
field penetration at any other point of the ESPE switches the OSSDs and stops the hazardous motion.
DANGER!
• All blanking functions described below impact reliable detection by the ESPE. A check
should therefore be carried out as part of a risk assessment to determine whether its use
is appropriate and permissible.
• Depending on the parametrized function, the resolution and the response time of the ESPE
may vary. This must be taken into account when calculating the safety clearance.
• Based on the parametrized function, the safety field must be checked for correct function
with the test rod (diameter according to the effective resolution).
• Further requirements and information on the use of the blanking function can be found in
the standard IEC 62046.
5.2.5.1 Principle
An object is located permanently in the safety field of the ESPE. To prevent the object from being classed as
a penetration, the beams covered by the object can be hidden using the blanking function.
Blocked beams
Object
Figure 18: Blanking principle
