C7061M MINIATURE DYNAMIC SELF-CHECK ULTRAVIOLET FLAME DETECTOR
65-0304—05
8
Fig. 7. Wiring diagram for C7061M Detectors with 7800
Series Flame Safeguard controls with shutter drive
circuitry.
IMPORTANT
Do not run the flame detector wiring in the same
conduit with high voltage ignition transformer wires.
Connecting Detectors in Parallel
For a flame that is difficult to sight, using two parallel C7061
Flame Detectors reduces nuisance shutdowns. If only one of
the parallel detectors loses the flame signal, the other indicates
the presence of the flame and keeps the burner running. When
two parallel C7061 Detectors are used, a flame-simulating
failure in either detector causes the burner to shut down. Two
C7061 Detectors can be connected in parallel to the same
terminals on 120 volt flame safeguard controls. To avoid
exceeding the rating of the solid-state shutter switch in the
R7861 Flame Signal Amplifier, do not connect more than two
C7061 Detectors in parallel.
When the flame detectors are connected in parallel, the low
level background signals are additive. This background signal
increases as the temperature decreases.
IMPORTANT
Voltage and frequency: The C7061 is powered from
the flame safeguard unit that delivers the necessary
voltages to operate the tube and shutter.
ADJUSTMENTS AND
CHECKOUT
UV Sensor Tube Test
For initial burner lightoff, consult the burner manufacturer
instructions or the flame safeguard control instructions.
If the system does not start during the initial burner lightoff,
check the UV sensor tube in the flame detector. If a reddish
glow appears when there is no flame present, replace the UV
sensing tube. When performing this test, make sure there are
no extraneous sources of ultraviolet radiation in the test area
[see “Radiation Sources (Other than Flame)” on page 4].
Adjust Detector Sighting
With the flame detector installed and the burner running, adjust
the sighting position of the detector for optimum flame signal.
It is suggested that a volt-ohm meter with a minimum sensitivity
of one megohm/volt and a zero to five or ten Vdc scale be used
for R7861 Amplifier flame signal measurements. Measure the
flame signal as illustrated in
Fig. 8. Be careful to make the proper connections of
positive (red) meter lead to positive (+) control jack and
negative (black) meter lead to negative (-) or (-Com) jack with
7800 Series controls. When the 7800 Series control has a
Keyboard Display Module, a zero to five Vdc voltage is
displayed on the module.
NOTES:
1.
The shutter operation may cause fluctuations in
the voltage reading. Read the average stable
reading, disregarding the peaks.
2.
The flame signal must be steady (or stable as
described in note 1).
Move the detector and sight pipe around to sight the flame
from various positions and angles. Try to get a maximum
steady (or stable) reading on the meter that is above the
minimum acceptable voltage listed in Table 1.
Measure the flame signal for the pilot alone, the main burner
flame alone, and both together (unless monitoring only the pilot
flame when using an intermittent pilot, or only the main burner
flame when using direct spark ignition). Also measure the
flame signal at low and high firing rates and while modulating in
between (as applicable). With the detector in its final position,
all required flame signals must be steady
(or stable) and as specified in Table 1. If you cannot obtain the
proper signal, refer to the Troubleshooting section.
WHITE
WHITE
YELLOW
BLUE
(G)
(F)
WIRING MUST BE NEC CLASS 1.
TERMINAL 5 – SHUTTER DRIVE - - - - - - -
TERMINAL 1 – NOT USED
TERMINAL 2 – FLAME OUTPUT - - - - -
TERMINAL 3 – FLAME PUTPUT - - - - -- - -
TERMINAL 4 – SHUTTER DRIVE - - - - - -
1
2
3
4
5
1 AN R7861 DYNAMIC SELF-CHECK AMPLIFIER MUST BE USED.
TWO C7061M DETECTORS CAN BE CONNECTED IN PARALLEL TO THE
SAME TERMINAL.
C7061M1016 ONLY: KEYED CONNECTOR ALLOWS CONNECTION IN ONLY
ONE POSITION.
C7061M1016 ONLY: REFERENCE MOLEX WOODHEAD 1R5006A20A120
(FORMERLY BRAD HARRISON™ 41310 TYPE CONNECTOR).
2
3
4
3
4
7800 SERIES
FLAME
SAFEGUARD
CONTROL WITH
SHUTTER DRIVE
CIRCUITRY
F
G
22
L2
M34066
