T874 MULTISTAGE THERMOSTATS AND Q674 SUBBASES
60-24858118
Fig. 87. Schematic and hookup of T874D with Q674E. Used in standard applications. Fig. 88. Schematic and hookup of T874B,D with Q674E. Used in standard applications.
C2
RISE
C1
RISE
H2
FALL
H1 FALL
L1
(HOT)
L2 1
L1
(HOT)
L2 1
2
1
2
POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.
FIELDWIRE JUMPER TO ALLOW SINGLE SYSTEM TRANSFORMER.
H1 ANTICIPATOR
H2 ANTICIPATOR
C1 ANTICIPATOR
C2 ANTICIPATOR
SYSTEM
SWITCH
FAN
SWITCH
AUTO
ON
OFF
HEAT
AUTO
COOL
COMPRESSOR
CONTACTOR 1
COMPRESSOR
CONTACTOR 2
M4668
1
SYSTEM
FAULT CONTACT
FAN RELAY
HEAT RELAY 1
HEAT RELAY 2
LOCKOUT LED
(RED)
THERMOSTAT SUBBASE SYSTEM COMPONENTS
W1
Y1
RC
W2
B
G
RH
C
X
Y2
11
10
9
8
6
4
C2
RISE
C1
RISE
H2
FALL
H1 FALL
L1
(HOT)
L2
1
L1
(HOT)
L2 1
1POWER SUPPLY. PROVIDE DISCONNECT
MEANS AND OVERLOAD
PROTECTION AS REQUIRED.
H1
ANTICIPATOR
H2 ANTICIPATOR
C1 ANTICIPATOR
C2 ANTICIPATOR
SYSTEM
SWITCH
FAN
SWITCH
AUTO
ON
OFF
HEAT
AUTO
COOL
COMPRESSOR
CONTACTOR 1
COMPRESSOR
CONTACTOR 2
M4669
1
FAN RELAY
HEAT RELAY 1
HEAT RELAY 2
HIGH LED (RED)
LOW LED (GREEN)
THERMOSTAT SUBBASE SYSTEM COMPONENTS
W1
Y1
RC
W2
G
RH
X
Y2
11
10
9
8
6
4