Honeywell C7024E User Manual page 8

C7024E,F
INSTALLATION
Fig. 9—Mounting C7024F Detector.
SCREW COUPLING
ONTO SIGHTING PIPE
COLLAR
HOLE KEYED
TO PIN ON
BODY FLANGE
WIRING
!
CAUTION
When using a C7024E or F with a R7824C Dy-
namic Self-Check Amplifier, be careful not to
short the white shutter leadwires together (by wir-
ing incorrectly, leaving an incorrect jumper wire,
or stripping the insulation so far that the bare
leadwires can touch). If the shutter leadwires are
shorted during the operation, the amplifier will be
permanently damaged and be nonoperative.
1. All wiring must comply with applicable local electrical
codes, ordinances and regulations. Use NEC Class 1 wiring.
2. Keep the flame signal leadwires as short as pos-
sible from the flame detector to the terminal strip or
wiring subbase. Capacitance increases with leadwire
length, reducing the signal strength. The maximum per-
missible leadwire length depends on the type of leadwire
and conduit type and diameter. The ultimate limiting
factor in flame signal leadwire length is the signal cur-
rent. Refer to Table 1.
3. The detector has color-coded plastic-insulated no.
18 leadwires, 8 ft [2.4m] long, rated for 221° F [105° C].
Run these wires in a conduit.
4. If the leadwires are not long enough to reach the
terminal strip or wiring subbase, make the required
splices in a junction box.
5. If splicing is necessary, use moisture-resistant no.
14 wire suitable for at least 167° F [75° C] if the detector
is used with a flame safeguard primary control, or at
least 194° F [90° C] if used with a flame safeguard
programming control.
6. For high temperature installations, use Honeywell
specification no. R1298020 or equivalent for the "F"
leadwire, which is rated up to 400° F [204° C] for continu-
ous duty and tested for operation up to 600 volts and for
65-0156—1
BODY FLANGE
PIPE
UNION
HEX-HEAD
COVER BOLT (6)
COVER
M1955
breakdown up to 7500 volts. For the other leadwire, use
moisture-resistant no. 14 wire selected for a temperature
rating above the maximum operating temperature.
7. Refer to Fig. 10 for wiring connections.
Fig. 10—Wiring diagram for C7024E,F Detec-
tors with RM7824 Flame Safeguard controls
with shutter drive circuitry.
FLAME SAFEGUARD
CONTROL
1
TERMINAL STRIP
F
G
22
L2
3
L2
4
1 A R7824C DYNAMIC SELF-CHECK AMPLIFIER MUST BE USED WITH
A RM7824 FLAME SAFEGUARD CONTROL INCORPORATING THE
SHUTTER DRIVE CIRCUIT.
2 VOLTAGE AND FREQUENCY RATING OF THE C7024E, F MUST MATCH
THE POWER SUPPLY OF THE FLAME SAFEGUARD CONTROL.
TWO C7024E, F DETECTORS MAY BE CONNECTED IN PARALLEL TO
3
THE SAME TERMINALS ON 24 Vdc CONTROLS ONLY.
THE ADDITIONAL YELLOW/GREEN LEADWIRE IS ONLY ON CERTAIN
4
C7024E MODELS THAT MEET BGC OR DIN REQUIREMENTS;
CONNECT YELLOW/GREEN WIRE TO SEPARATE GROUND TERMINAL
ON THE WIRING SUBBASE.
( ) IDENTIFICATION LABEL ON LEADWIRE.
5
IMPORTANT: Do not run the flame detector wiring in
the same conduit with high voltage ignition trans-
former wires.
CONNECTING THE DETECTORS IN PARALLEL
For a flame that is difficult to sight, using two parallel
C7024 Flame Detectors reduces nuisance shutdowns. If
only one of the parallel detectors loses the flame signal,
the other will indicate the presence of the flame and will
keep the burner running. If two parallel C7024E or F
Detectors (with self-checking shutters) are used, a flame-
simulating failure in either detector will cause the burner
to shut down. Two C7024E or F Detectors may be
connected in parallel to the same terminal on 24 Vdc
flame safeguard controls. To avoid exceeding the rating
of the solid-state shutter switch in the R7824C Flame
Signal Amplifier, do not connect more than two C7024E
or F Detectors in parallel.
IMPORTANT: Voltage rating of the C7024 must match
the power supply of the flame safeguard control.
8
2
3
C7024E, F
BLUE
YELLOW
WHITE (S)
5
WHITE (L2)
RED (+)
BLACK (-)
YELLOW/GREEN
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