Modbus — Onrobot

You write 100 (for 10.0 mm), but the gripper moves to 25600 . Cause: Modbus TCP is big-endian. Your PLC might be little-endian. A 16-bit register can be interpreted in reverse byte order. Fix: Swap the bytes in your PLC logic (e.g., using SWAP instruction in Siemens or BSWAP in Rockwell).