84
4
Quadrant
Energy Analyzer
4
Quadrant
Energy Analyzer
SECTION 4 MODBUS PROTOCOL
There should be a time gap, which is at least 3.5 characters wide, between RTU messages.
For instance, when client device requests any information, server device should reply
after at least a 3.5 character wide time gap. Following the response of the server, client
device should wait 3.5 characters long period, before requesting information again.
Data types used in KLEA are as follows
Tablo 4-2 int (32 bit) data type
b31 (Bit 31) ----------------------------------- b0 (Bit 0)
MSB (Most Significant Bit) ------------------------------------ LSB (Least Significant Bit)
int:
32-bit integer value. Byte order starts from the lowest byte address as b0, b1, b2 and so
on.
float:
It is a 32-bit flo ting-point number in IEEE 754 standard.
string:
Character array in ASCII standard. It is only used for Klea device name and Klea
configuration name variables.
4.4 Implemented functions for ModeBUS-RTU Protocol
Tablo 4-3 Implemented functions for ModeBUS RTU Protocol
Function Name Function Code
Read Holding Registers 03H (decimal value 3)
Write Single Register 06H (decimal value 6)
Write Multiple Registers 10H (decimal value 16)
Read file record 14H (decimal value 20)
4.5 Data and Setting Parameters for KLEA
4.5.1 Measured and Calculated Data
Calculated and measured data are “read-only” values.