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Operation
-
Operating
Modes
Release M
DR4500A Classic Series Circular Chart Recorder With or Without Control Product Manual
129
April 2017
5.6 Operating Modes
Available modes
The recorder can operate in any of three basic modes:
Manual
Automatic with Local Setpoint
Automatic with Remote Setpoint
Manual and Automatic with Local setpoint are standard features and Automatic with Remote Setpoint is
optional.
Mode definitions
Table 5-10 Operating mode definitions
Operating Mode
Definition
MANUAL
When switched to manual mode, the recorder holds its output at the last
value used during automatic operation and stops adjusting the output for
changes in setpoint or process variable.
Instead, you adjust the output by changing the value shown in the lower
display. See “
Selecting Modes”
.
AUTOMATIC with
LOCAL SETPOINT
In automatic local mode, the recorder operates from the local setpoint and
automatically adjusts the output to maintain the setpoint at the desired
value.
In this mode you can adjust the setpoint. See “
Setpoints
”.
AUTOMATIC with
REMOTE SETPOINT
In automatic remote mode, the recorder operates from the setpoint
measured at input 2.
Adjustments are available to ratio this input and add a constant bias
before it is applied to the control equation. See
subsection 3.10 Control
Set Up Group.
What happens when you change modes
Table 5-11 explains what happens to the recorder when you switch from one mode to another.
Table 5-11 Changing operating modes
Operating Mode
Definition
Manual to Automatic
Local Setpoint
The local setpoint is usually the value previously stored as the local
setpoint.
Manual or Auto Local to
Automatic Remote SP
The second input value with ratio and bias applied is used to calculate the
control setpoint.
Automatic Remote SP to
Manual or Auto Local
Setpoint
If configured for RSP Tracking, when the recorder transfers out of remote
setpoint, the last value of the control setpoint is inserted into the local
setpoint.
If RSP tracking is not configured, the local setpoint will not be altered
when the transfer is made. See
subsection 3.10 Control Set Up Group
"SP TRACK".
Selecting manual or automatic mode