Solid State Cooling Systems ThermoCube - Page 21

THERMOCUBE PAO CHILLER PART # 52-400-2G-1-PAO
SOLID STATE COOLING SYSTEMS, 167 MYERS CORNERS ROAD, WAPPINGERS FALLS, NY 12590 19
TELEPHONE: (845) 296-1300 FAX: (845) 296-1303 WEB: WWW.SSCOOLING.COM VERSION M9
RS-232 Communication Protocol
Table 2: Command and Data Bytes
Bit Position
Description
Bit =1
Bit = 0
Command
Byte
Bit 7 (MSB)
Set Remote Control
remote control
local control
(chiller)
Bit 6
Remote On/Off
chiller On
chiller in standby
Bit 5
Communication
Direction
remote to chiller
(command from master)
chiller to remote
(status from chiller)
Bits 4 – 0
Parameters being communicated (see table 2)
Data Bytes
1 or 2 bytes depending on parameter (see tables 3 and 4)
Timing: ThermoCube PAO can accept a maximum of three commands per second
Table 3: Control Parameter
Bits 4 – 0
Parameter
No of Data Bytes
00001
Chiller set point 1 temperature
2
01001
Current fluid temperature at chiller coolant output
2
01000
Faults from chiller (fan, pump, RTD failure, etc.)
1
Table 4: Temperature Data Bytes (2 bytes)
The 2 data bytes for the temperature set point and transmission of the current temperature represent the
value of the temperature in 0.1°F increments. For example:
Temperature (examples)
High Byte
Low Byte
Hexadecimal
0.1 F
00000000
00000001
0001
1.0 F
00000000
00001010
000A
10.0 F
00000000
01100100
0064
20.0 F
00000000
11001000
00C8
30.0 F
00000001
00101100
012C
40.0 F
00000001
10010000
0190
50.0 F
00000001
11110100
01F4
60.0 F
00000010
01011000
0258
70.0 F
00000010
10111100
02BC
Table 5: Faults Data Byte (1 byte)
0 = OK, 1 = Fault
Bit Position
Fault Assigned
Hex value when fault is present
0
Tank Level Low
01
1
Fan Fail
02
2
Unassigned
N/A
3
Pump Fail
08
4
RTD open
10
5
RTD short
20
6
Unassigned
N/A
7
Unassigned
N/A