Honeywell 7800 Series Manual page 16

RM7823A
CHECKOUT
• Flame signal measurement—all installations.
• Hot refractory saturation test—all installations using
Infrared (lead sulfide) Flame Detectors.
• Hot refractory hold-in test—all installations.
• Ignition interference test—all installations using
flame rods.
• Ignition spark pick-up—all installations using Ultra-
violet Flame Detectors.
• Response to other ultraviolet sources—all installa-
tions using Ultraviolet Flame Detectors.
• Flame signal with hot combustion chamber—all
installations.
• Safety shutdown tests—all installations.
See Fig. 14 for location of component parts and see
Fig. 7 or Q7800 Specifications for terminal locations.
PRELIMINARY INSPECTION
Perform the following inspections along with proce-
dures specified by the equipment manufacturer to avoid
common problems. Make certain that:
1. Wiring connections are correct and all the terminal
screws are tight.
2. Flame detector(s) is clean, installed and positioned
properly. Consult the applicable Instructions.
3. Correct combination of amplifier and flame detec-
tor(s) is used. See Table 2 in the Specifications.
4. Plug-in amplifier is securely in place.
5. Burner is completely installed and ready to fire; con-
sult equipment manufacturer instructions. Fuel lines are
purged of air.
6. Combustion chamber and flues are clear of fuel and
fuel vapor.
7. Power is connected to the system disconnect switch
(master switch).
8. Lockout switch is reset (push in reset pushbutton)
only if the RM7823A is powered, see Figs. 1 and 2.
9. System is in the STANDBY condition. POWER LED
is energized.
10. All limits and interlocks are reset.
Flame
Detector
Flame Rod
Photocell
C7012A,C
C7012E,F
C7015A
C7027A
C7035A
C7044A
C7076A,D
a
This minimum or a stronger signal should be easily obtained if the detector is correctly installed and positioned to properly
sense the flame. This voltage must be obtained before completing checkout.
b
The flame signal amplifier circuitry is tested one-half second every five seconds during burner operation and shuts down the
burner if the amplifier fails (all installations).
c
The flame amplifiers are AMPLI-CHECK™ type.
65-0106—2
FLAME SIGNAL MEASUREMENT
in the following checkout tests. Read the flame signal volts dc
at the flame amplifier test jacks + and—(Com).
flame amplifier. Insert the negative (black) probe into the—
(Com) jack of the flame amplifier.
ers, read the average stable voltage, disregarding the peaks
caused by the self-checking operation.
all tests are completed and all adjustments are made.
TABLE 5—FLAME SIGNAL.
Minimum
Acceptable
Flame Signal Steady Dc
Amplifier Voltage
c
R7847A,B 1.25 Vdc
b
R7847C
c
R7848A,B
c
R7849A,B
R7886A
16
Fig. 14—Flame signal measurement.
POSITIVE (+)
METER LEAD
NEGATIVE (-)
METER LEAD
Measure the flame signal at the appropriate times defined
1. Use a 20 kohm/voltmeter with a 0 to 10 Vdc capability.
2. Set the 20 kohm/voltmeter to the 0 to 10 Vdc range.
3. Insert the positive (red) probe into the + jack of the
4. Allow a few seconds for the meter reading to stabilize.
5. If using AMPLI-CHECK™ or shutter check amplifi-
6. The meter reading must be as specified in Table 5 after
Maximum
Expected
a
Dc Voltage
5.0 Vdc at the
Keyboard Display
Module
5.0 Vdc at a
volt-ohmmeter
20K OHM/
VOLT METER
M7554
or