Honeywell 7800 Series Product Data page 18

7800 SERIES RM7896A,B,C,D RELAY MODULE
INITIATE
LED
DISPLAY
BURNER
OPERATING
CONTROLS
AND
1
INTERLOCKS
FLAME
SIGNAL
1
Ignition Trials
1. Pilot Flame Establishing Period (PFEP):
a. The pilot valve and ignition transformer, terminals 8
and 10, are energized. The RM7896A,B has an
intermittent pilot valve, terminal 8. The RM7896C,D
has an interrupted pilot valve, terminal 8.
b. Flame must be proven by the end of the 4 or
10 second PFEP to allow the sequence to continue.
If flame is not proven by the end of PFEP, a safety
shutdown occurs.
c. At the end of PFEP, the ignition, terminal 10, is
de-energized.
2. Main Flame Establishing Period (MFEP):
a. After the Ignition Trials, and with the presence of
flame, the main fuel valve, terminal 9, is powered. If
a flameout occurs, the RM7896A,B will lockout or
recycle within .8 or 3 seconds, depending on the
Flame Failure Response Time (FFRT) of the
amplifier.
b. The RM7896C,D has a ten second MFEP. After the
Ignition Trials, and with the presence of flame, the
main fuel valve, terminal 9, is powered. If a flameout
occurs, the RM7896C,D will lockout within .8 or 3 sec-
onds, depending on the Flame Failure Response
Time (FFRT) of the amplifier.
INITIATE STANDBY
POWER POWER
PILOT PILOT
FLAME FLAME
MAIN MAIN
ALARM ALARM
65-0193
00 00
STANDBY START
POWER POWER POWER
BURNER/BLOWER MOTOR
LIMITS AND BURNER CONTROLLER CLOSED
AIRFLOW SW. CHECK
AIRFLOW INTERLOCK CLOSED
SAFE START CHECK
AIRFLOW SWITCH CHECK FEATURE IS FOR THE RM7896D.
Fig. 16. RM7896C,D sequence.
STANDBY: PURGE
F/G HOLD HOLD: F/G
(FLAME (FLAME
DETECTED) DETECTED) PURGE
POWER POWER POWER
PILOT PILOT PILOT
FLAME FLAME FLAME
MAIN MAIN MAIN
ALARM ALARM ALARM
Fig. 18. Sequence status LEDs.
00 10 10
TIMED PFEP
PURGE 4 OR 10 SEC MFEP
POWER POWER POWER
PILOT
PILOT PILOT
FLAME
FLAME FLAME
MAIN
MAIN MAIN
ALARM ALARM ALARM
4
IGN.
10
IGN./ PILOT 8
MAIN VALVE
DELAYED MAIN VALVE
L1 TO 6
6 TO 7
FLAME PROVING
RUN
1. The RM7896C,D has a delayed main valve. The
delayed main valve is energized once the RUN period
is entered.
2. The RM7896 is now in RUN and will remain in RUN
until the controller input, terminal 6, opens, indicating
that the demand is satisfied or a limit has opened.
RUN/TEST SWITCH
(RM7896C,D)
SEQUENCE
STATUS
LEDs
RESET
PUSHBUTTON
FLAME
SIMULATOR INPUT
Fig. 17. Sequence status LEDs.
RUN
(RM7896A,B
MAIN
PILOT INTERMIT-
IGNITION
IGNITION TENT PILOT)
POWER POWER POWER
PILOT PILOT PILOT
FLAME FLAME FLAME
MAIN MAIN MAIN
ALARM ALARM ALARM
18
POST PURGE
RUN 15 SEC STANDBY
POWER POWER POWER
PILOT
FLAME
MAIN
ALARM
9
21
AFSC
SSC
M7550
FLAME CURRENT
TEST JACKS
RUN
(RM7896C,D
INTERRUP- RESET
TED PILOT) POST PURGE ALARM
POWER POWER POWER
PILOT PILOT PILOT
FLAME FLAME FLAME
MAIN MAIN MAIN
ALARM ALARM ALARM
CAPTIVE
MOUNTING
SCREW
PLUG-IN
PURGE
CARD
DUST
COVER
RELAY
MODULE
FLAME
AMPLIFIER
M7552
M7551