Download Modicon Quantum

Configuring a Modicon Quantum Hot Standby with Unity System
Power-Up and IP
Address
Assignment
An NOE obtains its IP Address assignment at power-up as follows:
If the HSBY state is ...
Then the IP Address assigned is ...
Unassigned
Configured IP Address
Primary
Configured IP Address
Secondary
Configured IP Address + 1
Unassigned to Offline
See the Offline Mode at Power-up Sequence table following
If two NOEs power-up simultaneously, a "resolution algorithm" determines the
Primary NOE, and after determining the Primary NOE, the "resolution algorithm"
assigns the configured IP Address to the Primary NOE and then assigns the
configured IP Address + 1 to the Secondary NOE.
Offline Mode at Power-up Sequence table:
Offline Mode at Power-up Sequence
Result
Controller A powers-up before controller B
z IP Address of controller A is configured IP
Address
z IP Address of controller B is the configured
IP Address + 1
Both controller A and controller B power-up The resolution algorithm will assign controller A
a the same time
the configured IP address and will assign
controller B the configured IP address + 1.
The NOE performs a "duplicate IP" test by issuing an ARP request to the configured
IP Address. If a response is received within 3 seconds, the IP Address remains at
the Default IP and blinks a diagnostic code.
If no IP configuration exists, the NOE remains in standalone mode, and the IP
Address must be obtained from either a BOOTP server or from a MAC address.
103