Allen-Bradley Logix5000 Reference Manual page 159

Mnemonic Data
Type
.UnconnnectedTimeout DINT
.ConnectionRate DINT
.TimeoutMultiplier SINT
Description
Description
Time out for an unconnected message or for making a connection. The default value is 30 seconds.
If the message is Then
Unconnected The ER bit turns on if the controller doesn't get a response within the
UnconnectedTimeout time.
Connected The ER bit turns on if the controller doesn't get a response for making the connection
within the UnconnectedTimeout time.
Time out for a connected message once it has a connection. This time out is for the response from the other
device about the sending of the data.
· This time out applies only after the connection is made.
· The time out = ConnectionRate x TimeoutMultiplier.
· The default ConnectionRate is 7.5 seconds.
· The default TimeoutMultiplier is 0 (which is a multiplication factor of 4).
· The default time out for connected messages is 30 seconds (7.5 seconds x 4 = 30 seconds).
· To change the time out, change the ConnectionRate and leave the TimeoutMultiplier at the
default value.
The MSG instruction transfers elements of data.
This is a transitional instruction:
· In relay ladder, toggle the rung-condition-in from cleared to set each
time the instruction should execute.
· In structured text, condition the instruction so that it executes only on a
transition.
See Appendix
The size of each element depends on the data types you specify and the type of
message command you use.
Rockwell Automation Publication 1756-RM003N-EN-P - October 2011
Input/Output Instructions (MSG, GSV, SSV, IOT)
B.
Chapter 4
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