Lenze MCH Series Drives Modbus Communications - Manual (Page 31)

27 RG-MHMOD
Drive Control & Communication
Unlocking the Drive:
1. The first write necessary to the drive to perform any function (start,change speed, change a parameter,
etc) needs to be an unlock command.
To only control the drive over the network you can write a value of 0 to the drive’s Modbus register
40049 (AC Tech register 48).
To both control the drive and alter any programming parameters then write the drive’s programming
password to Modbus register 40049. The default password for the MCH drive is 0019.
2. You should only need to send the unlock command once after power up. As long as the communications
do not timeout you should not need to write another unlock to the drive before writing any other
function.
7.3 Basic Drive Commands
The following are the basic drive commands. ONLY ONE OF THESE CAN BE DONE AT A TIME:
1. To STOP the drive using the stop method programmed in Parameter 26 (STOP), write a value of 0004hex
to Modbus register 40002 (AC Tech register 1).
2. To Start the drive write a value of 0008hex to Modbus register 40002.
3. Drive direction cannot be contolled via Modbus on the MCH series drive.
4. If you want the network to control the speed of the drive, set Parameter 24 (Auto Source) to KEYPAD
and write the speed to the Keypad Speed Command Register, Modbus register 40041 (AC Tech register
40). Speed is written in 0.01Hz (so 4120 would be 41.20 Hz). In this mode the drive’s initial speed
reference on power up will be the last speed written to the drive.