Honeywell 7800 Series Manual page 12

RM7885A
WIRING
Fig. 8—High-low or modulating burner diagram.
S445A
START-STOP
STATION
STOP
B
INTERNAL
JUMPER
D
START
IGNITION
1
L1
(HOT)
L2
MASTER
SWITCH
1 120V, 60 Hz POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
2
DO NOT CONNECT ANY WIRES TO UNUSED TERMINALS.
Fig. 9 shows a recommended circuit for cascading two or
more burners. Each pilot is ignited and supervised by its
respective controller, ignition transformer, limit control,
flame detection system and RM7885A. The main gas valve,
however, is not energized until all pilots have been ignited
and proved, and their respective RM7885A flame relays have
pulled in. Failure of any of the pilots to ignite will prevent the
main gas valve from being energized.
120V ALARM
A
C
LOW FIRE MOTOR
END SWITCH
RECTIFYING FLAME
ROD, RECTIFYING
PHOTOCELL, OR INFRA-
RED (LEAD SULFIDE)
FLAME DETECTOR
OR
C7027A, C7035A, OR
WHITE
C7044A ULTRAVIOLET
FLAME DETECTOR
OR
C7012A,C,E,F OR
YELLOW
C7076A ULTRAVIOLET
FLAME DETECTOR
Q7800
G
L
2
DPST ALARM
(L1
3
SILENCING
)
SWITCH
4
5
6
LIMITS
7
INTERMITTENT
8
PILOT
9
1
0
F
BLUE
BLUE
WHITE
Fig. 10 shows typical connections for a combination gas-
oil application using high-low or modulating valves on both
fuel systems, and pilot ignition on both cycles. With the motor
end-switches and the R482B Relays connected as shown, a
guaranteed low fire start is assured on either cycle. Note that
the fuel switchover control switch is ganged.
Fig. 11 shows the connection for wiring the R4155A
Alarm Silencing Relay.
12
1
2
1
3
2
1
4
1
R482B
5
1
6
1
1 2 6 7 8
7
1
FUEL
8
PRESSURE
SWIITCH
1
9
CONTROLLER
2
MANUAL
0
VALVE
2
1
2
2
HI-LO OR
MODULATING
MOTOR
M5211
R W B
R W B
T T