Micromod MOD: Modcell 2050R Users Guide - Manual (Page 157)

IB-23C650
BASIC OPERATION
STARTUP
Procedures may vary from application to application, depending upon
individual requirements and controller setup. The initial operating mode
(usually manual), the set-point source (usually local), set-point value, and
controller output can be configured for specified safe values when power to
the controller is first applied. Each time a control application is first started up,
check all these items before turn-on.
Startup Without Set-Point Tracking
To start up the controller in the manual mode:
1. Place controller in manual mode with local set-point.
2. Adjust controller (local) set-point to starting value required for process
variable.
3. Adjust manual output of controller to a safe starting value for the process.
This is usually below 0% or above 100% of span.
4. Open block valve ahead of control valve or perform any other procedure
required to make the process variable available, such as starting a pump,
turning on a power supply, etc.
5. Manually adjust output of controller to bring process variable up to set-
point value. Ramping the output should be slow enough to allow the
process to respond to the change without overshooting the set-point.
Process is now operating under manual control with process at the set-
point.
Startup With Set-Point Tracking
The startup procedure is simplified when set-point tracking is used. With the
controller in the manual mode, the set-point tracks the process so that the
process and set-point values are together when the operator switches to the
automatic mode.
To start up the controller with set-point tracking:
1. Place controller in manual mode.
2. Adjust manual output of controller to a safe starting value for the process.
This is usually below 0% or above 100% of span.
3. Open block valve ahead of control valve or perform any other procedure
required to make the process variable available, such as starting a pump,
turning on a power supply, etc.
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