User Manual
EM303B General Purpose Inverter
10
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
demand, and meet needs of most of AC motor drives.
SVC 0—— Open-loop vector control without PG feedback
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.