P
AGE
46
Remote Setpoint (Optional)
The instrument setpoint can be adjusted by supplying a signal to the remote setpoint
terminals as indicated in the installation section. Local or Remote setpoint operation is
selected by pressing and releasing the SCROLL key until the upper display reads setpoint
select SPS. Press the DOWN key to enter the Setpoint Select mode. The lower display
will change to show the current setpoint mode, either local loc or remote rSP. To change
the setpoint mode press the SCROLL key. To exit the setpoint mode press the UP key.
To prevent unwanted setpoint mode changes, the Setpoint Select mode can be disabled in
the Enable mode, ESPS. When remote setpoint is active, the AUTO TUNE key is ignored.
Remote Selection of Dual Local Setpoint (Optional)
To use this feature, a remote dry contact closure needs to be connected to the instrument
between terminals 8 and 5 as shown in Section 2.2, page 11. In the Program mode, set
the setpoint configuration value to 3 - Local Dual Setpoint. Exit the Program mode and
follow the instructions for the Local Dual Setpoint to adjust the two setpoint values that are
desired. Return to the Program mode and change the setpoint configuration parameter
value from 3 to 4 - Remote Selection of Dual Local Setpoint. In this configuration, the
AUTO TUNE key is ignored.
When a dry contact closure is sensed between terminals 8 and 5, the setpoint value will be
the SP1 value. If no contact closure is sensed, the controller will be using the SP2 value.
The setpoint values can be adjusted by using the Digital Communcations Option. Refer to
the Protocol Manual (Form 2878) for more details about this option.
Process Re-transmission Output
If the instrument is provided with a current output not used for process control, this output
may be assigned to provide a linear re-transmission of the process value. This output can
be used to provide a process signal to remotely installed recorders, panel meters and
data loggers. The process output is scaled for the application by using the Program mode
parameters, process value upper Pou and process value lower PoL. The current output
resolution is 200 steps, so for the best re-transmission accuracy the span between Pou
and PoL should be as small as possible.
The example illustrated in Figure 4-4 shows a process re-transmission application for
0 to 200 degrees F.
FIGURE 4-4
PROCESS OUTPUT / RETRANSMISSION VALUES
EXAMPLE
INPUT
OUTPUT
0%
100 %
0
F
200
F
