Pcb Component Functions - Bryant SM03-4 Service Manual

INTERLOCK
DIODES
PLUG
TRANSFORMER
CONNECTIONS
8. T1, T2 and T3 are connections for the primary, high-voltage
side of the transformer.
9. The fan relay is controlled by the thermostat and turns the
fan on and off.
10. A plug is used as the connection for the PCB power and
electric heaters. Note the pin numbers on the plug.
11. Diodes provide DC power for the fan relay and the first
stage of electric heat: W2, W3 or E.
HK61GA001
2FC-1
HK61GA001A
C
3 2 1
6 5 4
9 8 7
12 11 10
TRANSFORMER
AC LINE
T1 T2 T3
COMMON DUMMY
240 VAC
Fig. 6—HK61GA001 Printed-Circuit Board
—9—
LOW VOLTAGE
TERMINAL BOARD
2ND STAGE
3RD STAGE
AUX1
24VDC
AUX2
F4
FAN
RELAY
F3
DUMMY
F2
DUMMY
L2 EAC2
FAN
F1
COMMON
L1 EAC1
240 VAC
ELECTRONIC AIR
CLEANER CONNECTIONS
II. PCB COMPONENT FUNCTIONS
A. Low-Voltage Terminal Board
The low-voltage terminal board connects the indoor thermostat to
the outdoor unit as shown in Fig. 8. The terminals are listed as
follows along with their functional control.
1. R is used to connect the secondary side of the transformer.
The red wire provides low voltage (24v) to the PCB and the
thermostat. R is fused on the HK61GA003 board.
ELECTRIC HEAT
BREAKOFF TABS
FOR STAGING
NOT USED
FUSE
(LOW VOLTAGE)
CONNECTIONS
FOR VARIOUS
ACCESSORIES
FAN CONNECTIONS
A97025