Hamilton Electronics EPHUM011 - page 25

pH ARC SensorsModbus RTU Programmer’s Manual (EPHUM011)
624300/01 page 25/ 67
2.5.5.2 Reading the measurementvalue of SMC
The registersdefi nedhere are used to read the measurement values of each SMC.
Start reg. Num-
ber of
reg.
Reg1 / Reg2 Reg3 / Reg4 Reg5 / Reg6 Modbus
function
code
Read
access Write access
Address 6 Physical unit Measurement
value of SMC Standard deviation 3, 4 U/A/S none
Figure 2.5.5.2.1:Definition of register at Address. Measurementv alue ofeach SMC.
Description Address Text Unit Minvalue Max value
SMC1 2472 R glass MOhm 30 600
SMC2 2504 R reference kOhm 0.25 100
SMC3 2536 R auxiliary kOhm 0.25 100
SMC4 2568 E pH vs. ref mV -900 900
SMC5 2600 E SG vs. ref mV -900 900
SMC6 2632 E auxv s. ref mV -50 50
SMC7 2664 E reference mV -900 900
SMC8 2696 pHact pH -0.5 14
SMC9 2728 T act K 253 403
Figure 2.5.5.2.2: Full list of register addresses for the measurement values of SMC1 to SMC9
Example:
Command: SMC1read Modbusaddress: 2472 Length: 6Type: 3Read
Parameter: Unit Value Standarddev.
Format: Hex Float Float
Value: 0x8000 247.56 0.02
Figure 2.5.5.2.3: Example to read register 2472. Physical unit is MOhm (0x8000), the measurement
value of SMC1is 247.66 MOhm, standard deviation of SMC1 is 0.02 MOhm