74
SVGm
Instruction Manual
8�2�- PROTOCOL
In the Modbus protocol, the
SVGm
uses the RTU (Remote Terminal Unit) mode.
The Modbus functions implemented in the device are as follows:
Functions 03 and 04
. Reading of n Words (2 bytes).
8�2�1�- EXAMPLE OF MODBUS QUERY
Query:
Value of the Load current of L1
Address
Function
Initial
register
No� of
registers
CRC
0 A
03
92
0002
xxxx
Address: 0A
, Peripheral number: 10 in decimal.
Function: 03
, Read function.
Initial Register: 92
, register from which to start reading.
No� of registers: 0002
, number of registers to be read.
CRC: xxxx
, CRC character.
Response:
Address
Function
No� of Bytes Register no� 1 Register no� 2
CRC
0 A
03
04
0000
00FA
xxxx
Address: 0A
, Responding peripheral number: 10 in decimal.
Function: 03
, Read function.
No� of bytes: 04
, No. of bytes received.
Register: 000000FA
, value of load current L1, with 1 decimal: 0xFA = 25.0 A
CRC: xxxx
, CRC character.
8�2�2�- MODBUS MAP
All Modbus map variables are in hexadecimal format.
For these variables,
Functions 03
and
04
are implemented.
8�2�2�1�- Load Measurements
Table 34: Modbus memory map: Measurements with Load�
Parameter
L1
L2
L3
LN
Units
Current with Load
92 - 93
94 - 95
96 - 97
98 - 99
[Low] + [Hi] A with 1 decimal
Active power with Load
AD - AE
AF - B0
B1 - B2
-
kW with 2 decimal places and sign.
Reactive power with Load
B3 - B4
B5 - B6
B7 - B8
-
kVar with 2 decimal places and sign.
Apparent power with Load
B9 - BA
BB - BC
BD - BE
-
kVA with 2 decimal places and sign.
cos
ɸ
with Load
D1
D2
D3
-
With 3 decimal
