Specifications

Control Properties
PlantScape Server and Client Configuration Guide 153
Control Modes
The current control mode of a point determines whether or not an operator is
permitted to control the OP or SP of the point.
The available control modes are: manual, automatic, cascade, and computer.
Cascade and computer are only available with specific controllers. Most
PlantScape device interfaces support just single bit modes (that is, values of 0 and
1, displayed by default as MAN and AUTO).
For PLC devices this is used to scan/control a bit within the controller that is used
for mode control within its logic. Other device interfaces define specific behavior
for the mode values (for example, S9000 supports this feature).
Normal Mode
When defining a point that includes a control you can specify what is to be the
“normal mode” for that point. The normal mode applies:
• By default for this point.
• When an authorized operator presses the appropriate function key(s) to
reset the mode after manual intervention. (For details, refer to the Operators
Guide.)
For most points, the normal mode is Auto.
Property Description
Man When the manual mode is set, an operator is permitted to change either the
set point or the output value.
Auto When the automatic mode is set, the controller itself (or sometimes the
PlantScape Server) controls the output and operators cannot change the
output value, unless “Disable mode checking on output” is set (see “Control
Confirmation” on page 152).
Casc Cascade mode is specific to S9000, TDC, and UDC controllers. The cascade
mode is used when the SP is coming from the output of another PID loop
within the controller (that is, PID loops are cascaded together). When the
mode is set to cascade, operators cannot change either the set point or the
output value.
Comp This mode is specific to TDC controllers. The computer mode is used when
the SP is coming from a computer that is performing automatic control.
When the mode is set to computer, operators can change either the set point
or the output values.
plscpcg.book Page 153 Monday, May 28, 2001 10:11 AM