Siemens SIMATIC IFP1200 Basic Operating Instructions Manual page 80

Markings and symbols
B.1 Safety-relevant symbols
Symbol Meaning
Only for industrial applications and indoor areas (control cabinet)
Install in control cabinet only
Devices approved for Ex Zone 2 in a control cabinet with min. IP54
Devices approved for Ex Zone 22 in a control cabinet with min. IP6x
80
Reference
Operating Instructions, 06/2023, A5E46178354 - AD
IFP Basic