Emerson ControlWave Instruction Manual page 76

ControlWave I/O Expansion Rack Instruction Manual
Software Configuration To use data from any ControlWave AO module in the rack you must
3-28
Figure 3-23. 4-20mA Current Loop AO - Wiring Diagrams
use ControlWave Designer's I/O Configurator to modify the
ControlWave project in the host controller to add an ER_AO8 board
and then configure it. See the ControlWave Designer Programmer's
Handbook (D5125) for more information. That same manual includes
an I/O Mapping section that describes, for advanced users, the I/O map
for this module.
AO with Readback in a Redundant System
Variables in the ControlWave project govern how inconsistencies
between the online AO module and the standby AO module are
handled in redundant systems with AO readback. Information on
configuring system variables is included in the ControlWave Designer
Programmer's Handbook (D5125).
If there is a difference of more than 0.5% (of span) between the value
of the online and standby AO values, a variable mapped by the
_ER_STAT virtual status board will be set TRUE. By default, the
name of the variable follows one of two possible formats.
where n is the I/O slot number of the virtual ER_STAT board, and x is
the I/O slot number of the analog output module. See the I/O
Configurator and I/O Mapping sections of the ControlWave Designer
Programmer's Handbook (D5125) for more information. You can
optionally rename these variables.
You should configure these variables as alarms so you receive
notification of a failure of the backup AO module. See the
ControlWave Designer online help for information on alarm
configuration.
When a read-back failure occurs, the FAIL LED remains RED until the
ERSTAT_n_RDN_IO_x_ERR
ERST_n_RDN_IO_x_ERR
I/O Modules Revised Aug-2015