20
Set How the Drive Stores Parameter Values
(Set the drive to store parameter changes in EEPROM)
By default, parameter changes made via Modbus RTU are only written to Random Access
Memory (RAM). When power to the drive is cycled, these changes are lost. Because it is
possible to write to parameters a large number of times using Modbus RTU, writing values
by default to RAM avoids subjecting the Electronically Erasable Programmable Read Only
Memory (EEPROM) to an excessive number of write operations. To write a parameter
change to the drives EEPROM, first write the value 1 to coil number 65. Then make the
parameter change. Afterwards, to keep future parameter changes from being permanent,
write the value 0 to coil number65.
Modbus RTU Function: 05
HEX
(Force Single Coil)
Overview:
•
Force coil number 65
10
to 1.
Message from Modbus RTU Master to Drive
Byte 0
Byte 1
Byte 2
Byte 3
Byte 4
Byte 5
Slave Address
Function
Coil Addr.,
High
Coil Addr.
Low
No. of Coils,
High
No. of Coils,
Low
01 05 00 40 FF 00
Byte 6
Byte 7
CRC Error Check
8D EE
Modbus RTU message string:
[01] [05] [00] [40] [FF] [00] [8D] [EE]
Coil Address: Coil Number 1 = 65 1 = 64
10
= 0040
HEX
.
Message returned from Drive to Modbus RTU Master
Byte 0
Byte 1
Byte 2
Byte 3
Byte 4
Byte 5
Slave Address
Function
Coil Addr.,
High
Coil Addr.
Low
No. of Coils,
High
No. of Coils,
Low
01 05 00 40 FF 00
Byte 6
Byte 7
CRC Error Check
8D EE
Example 6
{
Summary of Contents for Mobrus RTU TR1 Series
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