Carrier 30GN040-420 Refrigerator User Manual


 
PROCESSOR MODULE (PSIO) (Fig. 20)
Inputs Each input channel has 3 terminals; only 2 of the
terminals are used.Application of machine determines which
terminals are used. Always refer to individual unit wiring
for terminal numbers.
Outputs Output is 24 vdc. There are 3 terminals, only 2
of which are used, depending on application. Refer to unit
wiring diagram.
NOTE: Address switches (see Fig. 20) must be set at 01 (dif-
ferent when CCN connected).
LOW VOLTAGE RELAY MODULE (DSIO-LV) (Fig. 21)
Inputs Inputs on strip J3 are discrete inputs (ON/OFF).
When 24-vac power is applied across the 2 terminals in a
channel it reads as on signal. Zero v reads as an off signal.
Outputs — Terminal strips J4 and J5 are internal relays whose
coils are powered-up and powered-off by a signal from
microprocessor. The relays switch the circuit to which they
are connected. No power is supplied to these connections by
DSIO module.
4 IN/4 OUT MODULE (SIO) (Fig. 22) 4 In/4 Out mod-
ule allows the following features to be utilized:
1. Temperature Reset by outdoor air or space temperature.
A remote thermistor (Part No. 30GB660002) is also re-
quired.
NOTE: This accessory is not required for return water
temperature reset.
2. Temperature Reset by remote 4 to 20 mA signal.
3. Demand Limit by remote 2-stage switch.
4. Demand Limit by remote 4 to 20 mA signal
5. Dual Set Point by remote switch.
The options module is standard. Remember to reconfig-
ure the chiller for each feature selected (see Table 14). For
temperature reset, demand limit, and dual set point, desired
set points must be entered through keypad and display mod-
ule (see Set Point Function section on page 38).
See Table 19 for overall troubleshooting information.
ACCESSORY UNLOADER INSTALLATION
Some of the 30G Flotronic™ II units come standard with
unloader(s), and many permit additional unloader(s) to be
added if desired. See Table 20.
IMPORTANT: The following combinationsARE NOT
permitted (combinations are per circuit):
1. Two unloaders and hot gas bypass
2. Four compressors and 2 unloaders.
3. Four compressors, 1 unloader, and hot gas
bypass.
Fig. 19 Sensor Bus Wiring
(Communications)
PWR Power
Fig. 20 Processor Module (PSIO)
LEGEND
COMM Communications Bus
NC Normally Closed
NO Normally Open
PWR Power
Fig. 21 Low-Voltage Relay Module (DSIO)
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