Rockwell Automation 1746-NO8V SLC 500 8-Point Analog Output Module/ User Manual User Manual
Page 42
Publication 1746-UM026A-EN-P - September 2003
4-18 Configuring the Module
EXAMPLE 5: Set Preset Fault Values
Suppose you have a valve connected to Channel 7 with a 4 to 20
mA operating range and you want to use Engineering Units format.
You would use the following bit settings for the Channel 7
configuration word:
Suppose, also, that you would like the output to go to 12 mA if a
fault condition occurred. You would enter the following for Channel
7 data parameter 1. (Note that data parameter 2 is not used for the
Preset Fault Value.)
O:e.23
12000 (decimal) Channel 7 data parameter 1
Now set the bits in the Channel 7 configuration word:
Monitor bit 4 of Channel 7 Input Status Word 2 (I:e.15). When this
bit is a 1 (Preset Fault Value set), then set the Channel 7
configuration back to its original value with the addition of setting
the Channel 7 configuration word to Preset Output on Fault (bit 13):
If a fault is detected, then the output for Channel 7 will go to 12
mA.
Address
15
Channel 7 Configuration Word
0
O:e.15
0
0
0
0
0
0
0
0
0
0
0
1
0
0
1
1
Address
15
Channel 7 Configuration Word
0
O:e.15
0
0
0
0
1
0
1
1
0
0
0
1
0
0
1
1
Address
15
Channel 0 Configuration Word
0
O:e.15
0
0
1
0
0
0
0
0
0
0
0
1
0
0
1
1