Carrier 50TCQD17-D24 Service And Maintenance Instructions page 21

Fig. 30 - - Defrost Control Board (DFB) Arrangement
Inputs
Point Name
G Fan
Y1 Cool 1
Y2 Cool 2
W1 Heat 1
W2 Heat 2
R Power
C Common
DFT1
DFT 2
Outputs
Point Name
IFO Fan On
OF OD Fan On
RVS1
RVS2
COMP 1
COMP 2
HEAT 2
COM
Configuration
Point Name
Select Jumper
2 Compressor
Speed- - Up Configuration
Point Name
Speed --- Up Jumper
Speed --- Up Jumper
Jumper for 1- -3 seconds: Factory Test, defrost runs for 9 seconds
Jumper for 5- -20 seconds: Forced Defrost, defrost runs for 30 seconds if DFT2 is open
DIP
Switches
Speed-Up
Jumpers
C09275
Table 7. 50TCQ Defrost Board I/O and Jumper Configurations
Type of I/O Connection Pin Number
DI, 24Vac
DI, 24Vac
DI, 24Vac
DI, 24Vac
DI, 24Vac
24Vac
24Vac
DI, 24Vac DFT--- 1 to DFT--- 1
DI, 24Vac DFT--- 2 to DFT--- 2
Type of I/O Connection Pin Number
DO, 24Vac
DO, 24Vac
DO, 24Vac P3--- 7 to P3--- 5
DO, 24Vac P3--- 6 to P3--- 4
DO, 24Vac
DO, 24Vac
DO, 24Vac E--- HEAT
24Vac
Type of I/O Connection Pin Number
24Vac
24Vac
Type of I/O Connection Pin Number
The DFB is located in the 50TCQ's main control box (see
Fig. 31). All connections are factory- - made through
harnesses to the unit's CTB, to IFC (belt- - drive motor),
reversing valve solenoids and to defrost thermostats.
Fig. 31 - - Defrost Control Board (DFB) Location
Unit Connection
P2--- 3 LCTB--- G
P2--- 5 LCTB--- Y1
P2--- 4 LCTB--- Y2
P2--- 7 LCTB--- W1
P2--- 6 LCTB--- W2
P3--- 1 CONTL BRD--- 8
P3--- 2 CONTL BRD--- 4
Unit Connection
P3--- 9 REHEAT--- 2
OF
P3--- 10 FPT --- REHEAT--- 6
P3--- 8 REHEAT--- 8
HC --- 1 (TB4--- 1)
P3--- 3 HC --- 1 (TB4--- 3)
Unit Connection
P1--- 1
P1--- 3
Unit Connection
JMP17
JMP18
21
DEFROST
BOARD
(HP ONLY)
Note
Note
OFR
Energize in COOL
Energize in COOL
Note
Use for 50TCQD
Note
C12403