Carrier 48/50PD05 - Manual (Page 52)

52
Digital Scroll Control Board (DSC)
The DSC board controls the compressor’s capacity. (See Fig. 19
and Table 22.) It receives a 1--5vdc signal from the AUX1 board
determined by the cooling algorithm.
The DSC has direct control of the compressor and pulses a
solenoid unloader on and off to provide a specific capacity. The
discharge temperature thermistor (DTT) is monitored by the DSC
for compressor safety.
The DSC is equipped with an LED
(light--emitting diode) for diagnostics. See the troubleshooting
section for more details.
C08659
Fig. 19 -- Digital Scroll Controller (DSC)
Table 22 — DSC Connections
DISPLAY
NAME
POINT DESCRIPTION
SENSOR
LOCATION
TYPE OF I/O
CONNECTION
PIN NUMBER
INPUTS
CTLR Digital Scroll Ctrl Pwr 24 VAC 24VAC/24COM
Compressor Discharge Temperature (DTT) Discharge line 86k thermistor T1/T2
CAPC Compressor Capacity 1---5vdc C1/C2
Load Control Power* 19---250VAC L1/L2
OUTPUTS
C.ALM Scroll Compressor Alarm Relay A1/A2
CMP.A Compressor A Feedback Relay M1/M2
Digital Scroll Unloader
Compressor
section
Relay U1/U2
* Voltage used for contacts M1 & M2, U1 & U2, and V1 & V2 (24 VAC used).
48/
50P
D