Rockwell Automation 1771-OFE Analog Output Module Installation Instructions User Manual
Page 6

Analog Output Module
6
Publication 1771-IN044C-EN-P - October 2002
Voltage Output Version of the Module
If you are using the voltage output version (1771-OFE1), you must
set several configuration jumpers on the module’s circuit board. You
must set these jumpers before you can proceed with configuring the
module. When you set these jumpers, you configure each channel for
one of the three voltage ranges listed above. The module is shipped
with the jumpers in the +10V position.
Set the Last State Configuration Jumpers
The LAST STATE configuration jumpers determine the value of all
the module’s outputs whenever communication between the module
and the processor is lost. This condition occurs when a processor or
adapter faults, or the processor is placed in the PROG or TEST
mode, or if the remote I/O cable breaks.
This is a significant safety feature. You can choose to have the
module’s outputs go to the minimum, middle or maximum of their
respective ranges or hold their last state if a module or system fault
occurs or if the system processor changes from RUN to PROG
mode.
You do this by placing the LAST STATE configuration jumpers on
eight (four jumpers on sets of pins) of the stake pins corresponding
to MIN, MID or MAX. If you do not place configuration jumpers in
one of these positions, the module defaults to the HOLD LAST
VALUE setting.
IMPORTANT
•
On power-up, the module’s output is
disabled until the module receives the first
block transfer write. The output then enables
with the value that you send it in the block
transfer write block.
•
We ship 1771-OFE modules with the LAST
STATE configuration jumpers in the MID
position.
!
ATTENTION
Switch 1 of the I/O rack affects the function of the
configuration settings as indicated in the table below.
Rack Switch 1
Configuration Jumper Setting
Setting
MIN
MID
MAX
HOLD LAST STATE
Last State
Last State
Last State Last State
Last State
Reset
Min
Mid
Max
Last State
Rack switch 1 determines what output conditions occur during a rack
fault.