
244
• VACON®
apfiff09 marine
Local contacts: http://drives.danfoss.com/danfoss-drives/local-contacts/
7.12.8
Under load protection
The purpose of the motor under load protection is to ensure that there is load on the motor when the
drive is running. If the motor loses its load there might be a problem in the process, for example, a
broken belt or a dry pump.
The under load curve is a squared curve set between the zero frequency and the field weakening
point. The protection is not active below 5Hz (the under load time counter is stopped).
The torque values for setting the under load curve are set in percent which refers to the nominal
torque of the motor. The motor's name plate data, parameter motor nominal current and the drive's
nominal current I
H
are used to find the scaling ratio for the internal torque value.
P2.12.7.1 Under load protection ID713
“Underload Protec”
0
= No response
1
= Warning
2
= Fault, stop mode after fault according to Stop Function
3
= Fault, stop mode after fault always by coasting
If tripping is set active the drive will stop and activate the fault stage.
Deactivating the protection by setting the parameter to 0 will reset the underload time
counter to zero.
P2.12.7.2 Under load protection, zero frequency load ID715
“UP F0 Torque”
The torque limit can be set between 5.0
—
150.0% x TnMotor.
This parameter gives the value for the minimum torque allowed with zero frequency.
P2.12.7.3 Under load protection, field weakening area load
ID714
“UP fnom Torque”
The torque limit can be set between 10.0
—
150.0% x T
nMotor
.
This parameter gives the value for the minimum torque allowed when the output
frequency is above the field weakening point.
Underload
area
Torque
5 Hz
fn
Freq. Out
Содержание apfiff09 marine
Страница 1: ...vacon nx ac drives apfiff09 marine application manual ...
Страница 2: ......
Страница 310: ......