Open loop scalar mode
When EMCL works in open loop scalar mode, the motor is excited through direct voltage application, without taking into account sensor feedback. Whenever applicable (brushless AC, brushless DC or AC induction motors), the commutation frequency is also controlled. The following figure depicts a schematic of the open loop processing:
When using brushless motors, this mode generates a sinusoidal current at the specified frequency. Commutation sensors are not required.
Notice that maximum electric-energy-to-torque ratio can not be guaranteed in open loop mode.
Controlword in open loop scalar mode
The open loop scalar mode uses no mode specific bit of the controlword. The target voltage and frequency will be automatically processed after reception.
Statusword in open loop scalar mode
The open loop scalar mode uses no mode specific bit of the statusword.