ProFire PF2200-SB Product Manual page 22

2.1.2.17 TEMPERATURE CONTROL VALVE (TCV) OUTPUT
The Temperature Control Valve output (terminals 13-14) is a 4-20mA output that is intended to connect
to a proportional fuel gas valve on the main fuel train. The TCV output behavior corresponds to the
current state of the system, as outlined by the table below:
System State
Ready, Waiting, Alarm,
Lockout, Power On
Ignition
Main Light off
Transition from Main
Light Off to Process
Control
Process Control (PID)
Process Control (Staged
Heating, ON/OFF)
Where:
Purge Position: User configurable setting from 0-100% corresponding to valve opening
•
percentage (0% = 4mA, 100% = 20mA) – position held while the system is not running
• Pilot Position: User configurable setting from 0-100% corresponding to valve opening
percentage (0% = 4mA, 100% = 20mA) – position held during the Ignition state
TCV Minimum Position: User configurable setting from 0-100% corresponding to valve opening
•
percentage (0% = 4mA, 100% = 20mA) – the minimum position the valve can be told to go by the
Process Control state
Process Control Position: position of the TCV during process control. Either controlled by PID (if
•
enabled), or set to 100% in Staged Heating or On/Off control.
The TCV output also supports a manual override mode, where the output percentage is modifiable via
the user interface. When in manual override mode, the TCV output percentage is mapped to the
manual output position regardless of the system state.
TCV Position
Purge Position
Pilot Position
TCV Minimum Position
TCV Minimum Position -> Requested Process
Control Position
Requested Process Control Position
100%
Behavior
Holding
Holding
Holding
Ramping according to
ramp time setting
Actively controlled by PID
Output railed to
maximum value.
Section 2: PF2200-SB PRODUCT DESCRIPTION
V 4.0
Page 22 of 85