Bender B95061094, Руководство по установке

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Modbus TCP server
31 CP9xx-Kit_D00399_00_M_XXEN/07.2019
5.2.4.2 Reference value on channel 1
The following reference value is stored in this channel: 230.0 V undervoltage
Tab. 5.4: Reference data stored in channel 1
5.2.4.3 Reference value on channel 2
The following reference value is stored in this channel:12.34 A
Tab. 5.5: Reference data stored in channel 2
5.2.4.4 Explanation of how to access floating point values
The test value 12.34 can be read out via Modbus TCP using Modbus function 0x04 at the address 0x0014. The
test value has a size of 2 words.
Proceed as follows:
1. Determine the correct byte offset
Interpreting both words as unsigned integer values should result in the following values:
Word 1 with address 0x14: unsigned integer value => 16709 (0x4145)
Word 2 with address 0x15: unsigned integer value => 28836 (0x70A4)
2. Determine the correct byte or word swap
There are four different combinations of swapping. The only correct value is 12.34.
All swapping combinations are represented in the following table.
5.2.5 Channel descriptions for the process image
Word 0x10 0x11 0x12 0x13
HiByte LoByte HiByte LoByte HiByte LoByte HiByte LoByte
0x43 0x66 0x00 0x00 0x00 0x04 0x00 0x4D
Floating point value (Float) AT&T R&U Description
230.0 No/No Volt Undervoltage
Word 0x14 0x15 0x16 0x17
HiByte LoByte HiByte LoByte HiByte LoByte HiByte LoByte
0x41 0x45 0x70 0xA4 0x00 0x03 0x00 0x4A
Floating point value (Float) AT&T R&U Description
12.34 No/No Ampere Overcurrent
Hex value
sequence
Word 1 Word 2
Floating point value
Byte 1 Byte 2 Byte 3 Byte 4
CORRECT
A
41 B
45 C
70 D
A4
12.34
Word swapping
C
70 D
A4 A
41 B
45
4.066E+29
Byte swapping
B
45 A
41 D
A4 C
70
3098.27
Word and byte
swapping
D
A4 C
70 B
45 A
41
-5.21E-17
Value
Measured value description
alarm message operating
Note
0
1 (0x01)
Insulation fault
2 (0x02)
Overload
3 (0x03)
Overtemperature
4 (0x04)
Failure line 1