Process Control - ProFire PF2200-SB Product Manual

2.2.9 PROCESS CONTROL

Once the system has determined the mains can be turned on, it enters the Process Control state. In
this state, the system actively tries to maintain the process temperature setpoint via the actuation of
valves in various configurations. There are three main process control modes offered and they are:
1. On/Off Control
2. Staged Heating
3. PID Control
Any alarms or waits that occur during this state will force the system to transition to the Alarm state or
Waiting state, respectively.
In the Process Control state, the status of each powered outputs is as follows:
Powered Output
Pilot 1
Pilot 2
Coil 1 /2
SSV
HFV
2.2.9.1 ON/OFF CONTROL
This is the simplest mode of operation, requiring only the SSV outputs. In this mode, the SSV outputs
are Energized when the process temperature is below the process setpoint and are De-energized when
above the setpoint. In the case that the process temperature exceeded the setpoint, the temperature
must fall below the setpoint minus the dead-band in order for the SSV outputs to re-energize.
Note: this process control mode does not utilize the HFV or the TCV outputs.
Status
Energized
De-energized if disabled
Energized if enabled
De-Energized
Energized or De-energized, depending on process control
state. See process control modes below for detailed valve
behavior
Section 2: PF2200-SB PRODUCT DESCRIPTION
V 4.0
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