Honeywell 7800 Series Product Data page 7

15/16 [24] DIA.
2-1/2
(64)
1 (25)
2 (51)
PRINCIPAL TECHNICAL FEATURES
The RM7896 provides all customary flame safeguard
functions while providing significant advancements in the
areas of safety, annunciation and system diagnostics.
Safety Shutdown (Lockout) Occurs if:
1. INITIATE Period
a. Purge card is not installed or removed.
b. Purge card is bad.
c. Configuration jumpers have been changed (after
200 hours).
d. AC line power errors occurred; see Operation.
e. Four minute INITIATE period has been exceeded.
2. STANDBY Period
a. Flame signal is present after 40 seconds.
b. Airflow switch check feature model is selected and
the airflow switch is closed for 120 seconds with
controller closed (RM7896B,D).
c. Ignition/pilot valve/intermittent pilot valve terminal is
energized.
d. Main valve terminal is energized.
e. Delayed main valve terminal is energized
(RM7896C,D).
f. Internal system fault occurred.
g. Purge card is not installed or removed.
h. Purge card is bad.
2-5/32
1 INCH NPT
(55)
6-7/32)
(158)
6-19/32
(168)
15/16–18 UNC
(2 EACH)
Fig. 4. Ultraviolet detectors dimensions in in. (mm) continued.
CELL MOUNT
2-3/4
(70)
2 LEADS IN A
48 INCH [1.2 METER]
FLEXIBLE CONDUIT
BUSHING WITH
MAGNIFYING LENS
Fig. 5. Infrared detector dimensions in in. (mm).
7800 SERIES RM7896A,B,C,D RELAY MODULE
11-13/16 (300)
1-27/32
7-13/16 (198)
(47)
C7076D
HEAT BLOCK
1-5/8 (41)
1-1/16 (27)
1-1/4
1-1/4
(32)
(32)
APERTURE
3/4-14 3/4-14 NPSM
NPSM INTERNAL
THREADS
COLLAR, 3/4-14 NPSM
M1982A
INTERNAL THREADS
C7015
3. PREPURGE Period
a. Airflow lockout feature is enabled and the airflow
switch does not close after ten seconds or within the
specified purge card timing.
b. Flame signal is detected after 30 seconds.
c. Ignition/pilot valve/intermittent pilot valve terminal is
energized.
d. Main valve terminal is energized.
e. Delayed main valve terminal is energized
(RM7896C,D).
f. Internal system fault occurred.
g. Purge card is removed.
h. Purge card is bad.
4. Pilot Flame Establishing Period (PFEP)
a. Airflow lockout feature is enabled and the airflow
switch opens.
b. Ignition/pilot valve terminal is not energized.
c. No flame present at end of PFEP.
d. Main valve terminal is energized.
e. Delayed main valve terminal is energized
(RM7896C,D).
f. Internal system fault occurred.
g. Purge card is removed.
h. Purge card is bad.
7
5-13/16 (147)
5-13/16
(147)
M5084A
65-0193