Applied Air IOMDFCDFM-1, Руководство по эксплуатации

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SECTION VII - TROUBLE SHOOTING
HONEYWELL RM7897A1002, RM7897C1000
7800 SERIES RELAY MODULES
PRINCIPAL TECHNICAL FEATURES
The RM7897 provides all customary fl ame safeguard
functions as well as signifi cant advancements in 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. Confi guration jumpers have been changed (after
200 hours) - Fault Code 110.
d. AC line power errors occurred, see Operation.
e. Four minute INITIATE period has been
exceeded.
2. STANDBY PERIOD
a. Airfl ow lockout feature is enabled and the airfl ow
switch does not close after ten seconds or within
the specifi ed purge card timing.
b. Flame signal is detected after 240 seconds.
c. Ignition/pilot valve terminal is energized.
d. Main valve terminal is energized.
e. Delayed main valve terminal is energized
(RM7897C).
f. Internal system fault occurred.
g. Purge card is removed.
h. Purge card is bad.
i. Preignition Interlock open.
3. PREPURGE PERIOD
a. Airfl ow lockout feature is enabled and the airfl ow
switch
opens.
b. Ignition/pilot valve terminal is energized.
c. Main valve terminal is energized.
d. Delayed main valve terminal is energized
(RM7897C).
e. Internal system fault occurred.
f. Purge card is removed.
g. Purge card is bad.
h. Flame signal is detected for 30 seconds.
i. Preignition interlocks open durning stand by.
4. PILOT FLAME ESTABLISHING PERIOD (PFEP)
a. Airfl ow lockout feature is enabled and the airfl ow
switch
opens.
b. No fl ame signal at end of PFEP.
c. Ignition/pilot valve/intermittent pilot valve
terminal is not energized.
d. Main valve terminal is energized (RM7897A).
e. Delayed (second stage) main valve terminal is
energized
(RM7897C).
f. Internal system fault occurred.
g. Purge card is removed.
h. Purge card is bad.
5. MAIN FLAME ESTABLISHING PERIOD (MFEP)
(RM7897A, teminal 21)
a. Airfl ow lockout feature is enabled and the airfl ow
switch
opens.
b. Ignition terminal is energized.
c. Ignition/pilot valve terminal is not energized.
d. Main valve terminal is not energized.
e. Delayed main valve terminal is energized.
f. Loss of fl ame signal
g. Internal system fault occurred.
h. Purge card is removed.
i. Purge card is bad.
6. RUN PERIOD
a. No fl ame present (JR2 removed).
b. Airfl ow lockout feature is enabled and the airfl ow
switch
opens.
c. Interrupted pilot valve terminal is energized
(RM7897A, terminal 21).
d. Main valve terminal is not energized.
e. Delayed main valve terminal is not energized
(RM7897C).
f. Internal system fault occurred.
g. Purge card is removed.
h. Purge card is bad.
i. Ignition terminal is energized.
OPERATION
Sequence of Operation
The RM7897A has the operating sequences listed
below; see Fig. 5 and 6. The RM7897A LED provide
positive visual indication of the program sequence:
POWER, PILOT, FLAME, MAIN and ALARM.
Initiate
The RM7897A Relay Module enters the INITIATE
sequence when the relay module is powered. The
RM7897A can also enter the INITIATE sequence if the
relay module verifi es voltage fl uctuations of +10/-15%
or frequency fl uctuations of ±10% during any part
of the operating sequence. The INITIATE sequence
lasts for ten seconds unless the voltage or frequency
tolerances are not met. When not met, a hold condition
is initiated and displayed on the optional KDM for at
least fi ve seconds; when met, the INITIATE sequence
restarts. If the condition is not corrected and the hold
condition exists for four minutes, the RM7897A locks
out.