Rockwell Automation 442L-SFZNMN SafeZone Mini Safety Laser Scanner User Manual - Manual (Page 13)

Rockwell Automation Publication 10000337275 Ver 01—October 2014 11
Chapter 3 Product description
The SafeZone Mini works on the principle of time-of-flight measurement. It sends out very short pulses of infrared light
(send pulses). At the same time an “electronic stopwatch” is started. When the light hits an object, it is reflected and
received by the safety laser scanner (receive pulses). From the time between sending and reception (
t) the SafeZone
Mini calculates the distance to the object.
Fig. 2: Principle of operation,
rotation of the SafeZone Mini
In the SafeZone Mini there is also a mirror rotating at constant speed that deflects the light pulses such that they cover an
arc of 270°. In this way an object can be detected in the protective field within 270°. The first beam of a scan starts at –45°
relative to the back of the safety laser scanner.
The SafeZone Mini sends a pulse of light with an angular resolution of 0.5° . As a result resolutions between 30 mm
(1.18 in.) and 70 mm (2.76 in.) can be achieved  .
Due to its active scanning principle, the SafeZone Mini does not require receivers or reflectors. This has the following
advantages:
•
Your installation effort is lower.
• You can easily adapt the monitored area to the hazardous area on a machine.
• In comparison with contact sensors, electro-sensitive scanning is nearly wear-free.
Field set comprising protective field and warning field(s)
Protective fields and warning fields form the so-called field set. You can configure these field sets with the aid of the SCD
software. The fields can be configured as circular, rectangular or of arbitrary shape. If the area to be monitored changes,
then you can re-configure the SafeZone Mini in software without additional mounting effort.
You can configure field sets comprising one protective field and one or two warning fields.
The SafeZone Mini secures the hazardous area on a machine or vehicle. As soon as the safety laser scanner detects an
object in the protective field, it switches the OSSDs to the OFF state and thus initiates the shutdown of the machine or stop
of the vehicle.
Fig. 3: Field set with one
protective field and
two warning fields
You can define the warning fields such that the safety laser scanner detects an object before the actual hazardous area.
Warning field 1 can be used in particular for vehicle protection to detect an object even before the actual hazardous area
and to slowly retard the movement of the vehicle or bring it to a standstill. In this way the wear on the brakes on an AGV
can be reduced. Warning field 2 can also be used to trigger a warning signal.
225°
-45°
90° 0°


180°
Protective field
Warning field 1
Warning field 2