Hot Standby Switchover

140NOC78•00 IP Address Swap Time

The following table details the 140NOC78•00 module IP address swap time in a Quantum EIO Hot Standby system:

Maximum swap time	500 ms (IP address swapping) + connection establishment time (3 s)
Recommended setting for implicit message	Set RPI to 1/2 of MAST cycle time (50 ms maximum)

Timeout multiplier setting:

MAST Cycle Time (ms)	Recommended RPI (ms)	Timeout Multiplier	Connection Timeout (ms)
20	10	16	160
50	25	8	200
100	50	4	200
200	50	4	200
255	50	4	200

NOTE: The maximum swap time may increase if the end device does not respond in a timely manner.

NOTE: During the swap, there may be disruption in communication between the 140NOC78•00 module and the end device. Confirm that the application can tolerate this communication disruption.

implicit messaging

UDP/IP-based class 1 connected messaging for EtherNet/IP. Implicit messaging maintains an open connection for the scheduled transfer of control data between a producer and consumer. Because an open connection is maintained, each message contains primarily data, without the overhead of object information, and a connection identifier.

RPI

(requested packet interval) The time period between cyclic data transmissions requested by the scanner. EtherNet/IP devices publish data at the rate specified by the RPI assigned to them by the scanner, and they receive message requests from the scanner at each RPI.

MAST

A master processor task that is run through its programming software. The MAST task has 2 sections:

IN: Inputs are copied to the IN section before execution of the MAST task.
OUT: Outputs are copied to the OUT section after execution of the MAST task.