Position
D
rive to Ignition Position
Preignition (Spark) = ON
Main Valve = ON
Ignition (Spark) = OFF
Interval 1
(Main Stabilization)
Operation 1
(Normal Operation)
Operation 2
(Driving to Low Fire)
Afterburn Time
Drive to Postpurge Position
Mandatory Postpurge
Optional Postpurge
Evacuate
Atmospheric Test
Fill
Pressure Test
Gas Shortage
Phase 00 02 10 12 22 24 30 35 36 38 40 42 44 60 62 70 72 74 78 80 81 82 83 90
Terminal Description Notes
X3-04.1
Safety Loop (Limits)
M
X5-03.1
On / Off Switch
M
N/A
Flame Signal
X X X X X M F X X X X X
X3-02.1
Blower Air Switch (APS) Note 1
F X M
X5-01.2
Low Gas Pressure Switch Note 2
High Gas Pressure Switch Note 2, 3
POC Note 3
F X M
X9-04.2
Valve Proving Pressure Switch
M F X
X3-05.1
Fan
X X X X X
X3-05.3
Continuous Fan
X4-02.3
Ignition
X X X X X X X X X X X X X X X X X X X X X X
X3-05.2
Alarm Note 4
X X X X X X X X X X X X X X X X X X X X X X
X6-03.3
Gas Valve SV (Usually Outdoor)
X X X X X
X8-02.1
Gas Valve V1 (Main, Upstream)
X X
X X X X X X X X X X X X X X X X
X7-01.3
Gas Valve V2 (Main, Downstream)
X X X X X X X X X X X X X X X X X X
Legend :
M
F
X
OUTPUTS INPUTS
Shutdown valve proving, if used.
GAS VALVE PROVINGSTART-UP SHUTDOWN
OPER-
ATION
Parameter 208 (Program Stop)
X5-02.2
Energized
Energized or de-energized
De-energized
Must be energized by end of phase