Honeywell 7800 Series Installation Instructions Manual page 29

STANDBY
INPUT &
OUTPUT
SIGNALS
STANDBY-
PURGE
POWER
POWER
PILOT
FLAME
MAIN
ALARM
IGNITION- T10
PILOT- T8
MAIN- T9
AIR VALVE- T5
FLAME PROVEN- T21
ALARM- T3
MOTOR POSITION- T12-T15 L/H/MOD
@ LOW FIRE INPUT- T18
LIMITS COMPLETE- T7
SF1 SPECIAL FUNCTION- T6
SF2 SPECIAL FUNCTION- T17
SF3 SPECIAL FUNCTION- T19
SF4 SPECIAL FUNCTION- T20
FLAME SENSED
*RM7888A1001 AND A1019 ARE 4 SECONDS. RM7888A1027 IS 10 SECONDS.
Fig. 23. DSI High/Low Stepfire sequence timing diagram.
RM7888A 7800 SERIES RELAY MODULE
HIGH/LOW HIGH/LOW HIGH
STEPFIRE- STEPFIRE-
PART 1* PART 2
2 TO 2 TO
INFINITE INFINITE
SECONDS SECONDS
POWER POWER
POWER
PILOT PILOT PILOT
FLAME FLAME FLAME
MAIN
L L MOD
29
RETURN TO
HIGH/LOW
STEPFIRE-
PART 2
POWER
PILOT
FLAME
(SEE
PREVIOUS
COLUMN
FOR PART 2)
M9499B
32-00214—01