Operating Setpoints Configuration - CleaverBrooks CEJS Installation, Operation And Maintanance

Electrode Boiler

7.12-Operating Setpoints Configuration

The Operating Setpoints configuration screen
allows the user to enter specific setpoints for
normal boiler operations. The remote pressure
and power limit setpoints as well as the power
limit and scaling factors can be set/enabled from
this screen. These operating setpoints are
typically determined at startup. The user must
be logged on to modify operating setpoints.
Factory Settings can be accessed from this
screen.
The following is a descriptive list of the operating
setpoint variables:
• Heater Off Pressure (psi)
Defines the pressure setting at which the back-up heating elements turn-off.
• Press for Release to Mod (psi)
Defines the pressure setting to allow the shield to modulate and control to setpoint after start-up. Until
this setpoint is reached, the shield ramp is moved incrementally based on the setpoints on the Factory
Settings screen. This sepoint is duplicated on the Software Switch Settings (Soft Switch SPs) screen
as the PSL setting.
• Backpress. Hysteresis
Defines the value at which the back-pressure valve begins to modulate into a closed position. The valve
starts closing when the pressure drops below the setpoint value minus the "Backpress. Hysteresis"
value. This creates a deadband/buffer zone for the modulated closing of the valve.
• Press to Limit FW Vlv (psi)
Defines the pressure setting that limits the feedwater valve position during start-up. This setpoint is
duplicated on the Software Switch Settings (Soft Switch Sps) screen as the PSLL setting. When the
boiler pressure is below this set point, the travel of the feed water valve is limited to the High Press
Limit FW Vlv (psi) setpoint value on the Operating Setpoints screen.
• Low Press Limit FW Vlv (%)
Defines the percentage in which the feedwater valve is opened when the boiler pressure is below the
feedwater valve pressure limit setting.
• High Press Limit FW Vlv (%)
Defines the percentage in which the feedwater valve is opened when the boiler pressure is above the
feedwater valve pressure limit setting.
• Chem Pump Stop (s)
Defines the upper conductivity limit at which the chemical pump stops supplying chemicals to the
system.
• Blowdown Vlv Open ( s)
Defines the upper conductivity limit at which the blowdown valve opens to purge the system.
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