PRON NA60-MB0
Version 3.50
PRON NA60-MB0 Remote Setting Manual
Page: 15 of 59
4 Examples
For all the examples, the following symbols are assumed:
S
= Slave Modbus address (1-247)
F
= Modbus Function code (1,2,3,4,5,6,15,16)
B
= number of byte in the DATA field
ADR
= Modbus DATA address
DIM
= number of Modbus DATA address
CRC
= Cyclical Redundancy Check
DATAx
= register x of DATA field
VALx
= value x of the variable
4.1 Example 1. How to read a variable
Let’s read from the Slave address 1 the value of the “Relay phase nominal current - In ”.
From the Address Data Table (Appendix A) we find out the following information;
VAR
REF IDX DIM
TYPE
UM Kv
ENUM
Relay phase nominal current - In
3x
50
1
UWORD
A
1
The REF field value specify an Input Register (3x), so the function 0x04 is used for reading. From the IDX the
Modbus address is derived: Modbus address = IDX -1 = 50 - 1 = 49. DIM specify the number of register to be read.
01
04
00 3E
00
02
-
-
TX
S
F
ADR
DIM
CRC
01
04
04
00
05
-
-
RX
S
F
B
DATA
CRC
The TYPE field value is equal to UWORD. Applying the rules described in the chapter 2.1, the following value is
obtained
VAL = 0x0005= 5.
Il UM field specify the Unit of measure that is “Ampere”, while Kv = 1 means that the value doesn’t need to be
scaled. The “Relay phase nominal current – In” is equal to 5A.
