6.2 Risk of explosion when pressing the button (ATEX, IECEx)
WARNING
EXPLOSION HAZARD
Do not press the SELECT/SET button when there is an explosive atmosphere.
Note
Commissioning devices with redundancy mechanisms
If you use redundancy mechanisms ("HRP" media redundancy or "MRP" and/or redundant 
coupling of rings over standby coupling), open the redundant path before you insert a new or 
replacement device in an operational network. A bad configuration or attachment of the 
Ethernet cables to incorrectly configured ports causes overload in the network and a 
breakdown in communication.
A device may only be inserted in a network and connected in the following situations:
● HRP/MRP:
The ring ports of the device being inserted in the ring were configured as ring ports. The 
required redundancy mode must also be enabled (see "Configuration Manual SCALANCE 
X‑300 / X‑400", section "X‑300 Ring Configuration"). If the device is intended to operate as 
the redundancy manager, "Redundancy manager enabled" must also be set.
● Standby coupling:
"Standby connection" must be "enabled" and the "Standby connection name" must match 
the name of the partner device. You will also need to configure the port with "Enable Standby 
Port Monitoring" (see "Configuration Manual SCALANCE X‑300 / X‑400", section "X‑300/
X‑400 Standby Mask").
Connecting
6.2 Risk of explosion when pressing the button (ATEX, IECEx)
SCALANCE X-300
Compact Operating Instructions, 11/2019, A5E00982643-18 51