User Manual Instruction Manual

Application Notes 13-13
Not to be confused with Sensorless Vector above, Encoderless Vector is
based on a patented field oriented control technology; a feedback device is
not
required. Torque control can be achieved across a significant speed
range without feedback.
2. Closed Loop (with Encoder)
Vector control with encoder feedback utilizes sophisticated drive control
algorithms. This technology allows the drive to control torque over the entire
speed range, including zero speed. For those applications that require
smooth torque regulation at very low speeds or full torque at zero speed,
Closed Loop Vector Control is the answer.
Speed Regulators
The GV6000 (Volts/Hz, Sensorless Vector or Vector) can be set up to regulate speed.
Speed regulation and torque regulation must be separated to understand drive
operation.
The GV6000 can offer improved speed regulation by adding speed feedback. Using a
speed feedback device (encoder) tightens speed regulation to 0.001% of base speed
and extends the speed range to zero speed.
13.6 Motor Overload
For single motor applications the drive can be programmed to protect the motor from
overload conditions. An electronic thermal overload I
2
T function emulates a thermal
overload relay. This operation is based on three parameters; Motor NP FLA (42),
Motor OL Factor (48) and Motor OL Hertz (47).
Motor NP FLA (42) is multiplied by Motor OL Factor (48) to allow the user to define the
continuous level of current allowed by the motor thermal overload. Motor OL Hertz
(47) is used to allow the user to adjust the frequency below which the motor overload
is derated.
The motor can operate up to 102% of FLA continuously. If the drive had just been
activated, it will run at 150% of FLA for 180 seconds. If the motor had been operating
at 100% for over 30 minutes, the drive will run at 150% of FLA for 60 seconds. These
values assume the drive is operating above Motor OL Hertz (47), and that Motor OL
Factor (48) is set to 1.00.