Schematic And Hookup Of T874A With Q674C. Used In Standard Applications; Schematic And Hookup Of T874A-D With Q674C. Used In Standard Applications - Honeywell T874 Product Data

T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
THERMOSTAT
H1
ANTICIPATOR
H1 FALL
RISE
C1
C1
ANTICIPATOR
THERMISTOR
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
2
MOMENTARY POSITION. SPRING RETURN TO "ON" UPON SWITCH RELEASE.
3
FILTER LED ON SELECT MODELS.
Fig. 75. Schematic and hookup of T874A with Q674C. Used in standard applications.
THERMOSTAT
H1 ANTICIPATOR
FALL
H1
FALL
H2 ANTICIPATOR
H2
C1
RISE
C1 ANTICIPATOR
RISE
C2
C2 ANTICIPATOR
2
1
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
2
FOR T874C, DELETE C2.
Fig. 76. Schematic and hookup of T874A-D with Q674C. Used in standard applications.
60-2485—8
SUBBASE
1
SYSTEM SWITCH
OFF
AUTO
4
FAN SWITCH
8
AUTO
ON
2
9
10
11
12
SUBBASE
FAN
1
SWITCH
AUTO
ON
4
6
8
SYSTEM
SWITCH
9 OFF
AUTO
10
11
3 FILTER LED ON SELECT MODELS.
112
SYSTEM COMPONENTS
W1
HEAT RELAY
FILTER LED
(YELLOW)
3
X
A
SERVICE
LED (RED)
FAN RELAY
G
R
O
MOMENTARY
CIRCUIT
O
Y
COMPRESSOR CONTACTOR
T
EXTERNAL
TEMP.
READOUT
T
W1
HEAT RELAY 1
W2
HEAT CHANGEOVER
VALVE
B
RH
RC
COOL CHANGEOVER
VALVE
O
G
Y2
COMPRESSOR
CONTACTOR 2
Y1
FILTER
3
LED (YEL)
X
SERVICE
LED (RED)
A
1
L1
(HOT)
L2
M5731
SYSTEM COMPONENTS
HEAT RELAY 2
L2
1
L1
(HOT)
L1
(HOT)
L2
1
FAN RELAY
COMPRESSOR
CONTACTOR 1
M7025