Carrier 48/50PD05 Air Conditioner User Manual


 
52
Digital Scroll Control Board (DSC)
The DSC board controls the compressor’s capacity. (See Fig. 19
and Table 22.) It r eceives a 1--5vdc signal from the AUX1 board
determined by the cooling algorithm.
The DSC has d irect control of the co mpressor 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 2 2 — DSC Connections
DISPLAY
NAME
POINT DESCRIPTION
SENSOR
LOCATION
TYPE OF I/O
CONNECTION
PIN NUMBER
INPUTS
CTLR DigitalScrollCtrlPwr 24 VAC 24VAC/24COM
Compressor Discharge Temperature (DTT) Discharge line 86k thermistor T1/T2
CAPC Compressor Capacity 1 --- 5v dc 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
DigitalScrollUnloader
Compressor
section
Relay U1/U2
* Voltage used for contacts M1 & M2,U1 & U2, and V1 & V2 (24 VAC used).
48/50PD