Siemens Simatic S7-1500R System Manual page 132

Safety information
Personal injury or material damage can occur in zone 2 hazardous areas
If you remove or attach a synchronization module during operation, personal injury and
damage can occur in hazardous areas of zone 2. Always disconnect the R/H-CPU from the
power supply before you remove or attach a synchronization module in hazardous areas of
zone 2.
The synchronization module contains a laser system and is classified as a "CLASS 1
LASER PRODUCT" in accordance with IEC 60825-1.
Can cause personal injury.
Avoid direct eye contact with the laser beam. Do not open the housing. Read the
information in the system manual carefully.
Figure 5-10
S7-1500R/H redundant system
System Manual, 10/2018, A5E41814787-AA
WARNING
CAUTION
Class 1 laser products
5.9 Connecting interfaces for communication with S7-1500H
Wiring
131