30 | Appendix B: Modbus ASCII Parameter Table
Thermo Fisher Scientific ULT Freezers
Appendix B: Modbus ASCII
Parameter Table
The MODBUS interface is intended to be used with cable DLCPTDATA101 (328928H02)
If you plan to use your own harness:
J6, pin 3 is RS485A
J6, pin 2 is RS485B
J6, pin 5 is ground
Protocol
MODBUS ASCII
Baud Rate
2400bps to 57.6Kbps
Data Bits
7
Stop Bits
1
Parity
Even
Flow Control
None
Address
0 to 255
S.No
Parameter
Function
code
Address in
hexadecimal
Size
Modbus
command
Relay
Enclosure
Response
Data
Data
Type
Remarks
1
cabinet
setpoint (c)
0x03
530
2
3a 31 39
30 33
30
35 33 30
30 30 30
32 41 44
0d 0a
3A 31 39
30 33 30
34
46 46
46 46 46
43 45 30
30 32 0D
0A
0xFFF
FFCE
0
int
Convert the data value
into signed 2's
complement and divide
with 10, which gives the
setpoint.
Ex: Signed 2's
complement
of the 0xFFFFFCE0 is
equal to 800.
–800/10= –80.
So the setpoint is –80C.
2
Warm
Alarm
Setpoint
(C)
0x03
538
2
3a 31 39
30 33
30
35 33 38
30 30 30
32 41 35
0d 0a
3A 31 39
30 33 30
34
46 46
46 46 46
44 34 34
39 44 0D
0A
0xFF
FFFD
44
int
covert the data value int0
signed 2’s complement
and divide with 10, which
gives the setpoint.
EX: signed 2’s comple
-
ment of the 0xFFFFFD44
is equal to -700.
-700/10=-70.
so the WA setpoint is
-70C.
