User Manual EM303B General Purpose Inverter 1.2 Definition of EM303B Operation Status 1.2.1 Operation Status of Inverter Parameters setting status After power is on, inverter finishes initialization and enters standby status without fault or start-up command. Meanwhile, it does not output. Normal running status After receiving active start command through keypad, control terminal or RS485, the inverter drives motor in accordance with the requirements of setting input. JOG running status Set by keypad, external terminal or RS485 to make motor run as per JOG input speed.
JOG stop status Refer to the process that the output frequency drops to zero in JOG deceleration time after JOG running command is not active. Autotuning status Set by keypad to autotune motor’s parameters in stationary or rotational autotuning. Stop status Refer to the process that the output frequency drops to zero in given deceleration time after running command is not active. Fault status Status of inverter at protections, all kinds of faults and failures. 1.2.2 Control Modes of Inverter The control modes of inverter refer to that the inverter controls motor rotation as per required speed and torque with open loop or close-loop control mode. The control modes include:
General open loop space vector control——V/F control Applicable to the applications of low speed changes and low speed stability accuracy SVC 0—— Open-loop vector control without PG feedback demand, and meet needs of most of AC motor drives. Only estimate speed in real-time, but no feedback control. Output current is under real-time close-loop control, output of motor reaches 150% of rated torque at 0.5Hz, and inverter automatically traces load variables and limit output current to make it not exceed the maximum value.
Even if there is sudden load change, quick acceleration or deceleration, inverter will not trip overcurrent, short-circuit, and etc., and keep high performance and reliability. SVC1—— Torque control(Close-loop vector control without PG feedback) Not only estimate speed in real-time, but also conduct feedback control. Speed and current are under real-time close-loop control. Not only speed control but also torque control can be realized. A regular AC induction motor can perform as an AC variable speed motor and an AC torque motor by adopting this control mode. It is a genuine sensorless vector control. 10