Honeywell 7800 SERIES

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