Magnetek IMPULSE VG+ Series 3, Instruction Manual, Page: 132 / 183

IMPULSE•VG+ Series 3 Instruction Manual – 07/25/05
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Protection Parameters
• L1 Motor Overload
• L2 Under Voltage Level
• L4 Ref Detection
• L6 Torque Detection
• L8 Hardware Protection
• L9 Automatic Reset
Motor Overload
The IMPULSE•VG+ Series 3 protects against motor overload with a UL-recognized, built-in
electronic thermal overload function.
The electronic thermal overload function estimates motor temperature, based on inverter output
current, frequency and time to protect the motor from overheating. When the thermal overload fault
is activated, an “OL1” trip occurs, shutting OFF the inverter output and preventing excessive
overheating in the motor. As long as the inverter is powered up, it continues to calculate the motor
temperature.
When operating with one inverter connected to one motor, an external thermal relay is not needed.
When operating several motors with one inverter, use the internal thermal protection from the motor
or install an external thermal overload relay on each motor. In this case, set parameter
L1-01 to “0.”
Parameter
Code
Display Function Range
Initial
Value Access
Level
L1-01 MOL Fault Select Enable/disable motor
overload detection. 0-3 3 Adv
0 Disabled
1 Std Fan Cooled
2 Std Blower Cooled
3 Vector Motor
L1-02 MOL Time Const Time for OL1 fault when
motor current is
≥
150% of
the motor rated current.
0.1–20.0 min 8.0 Adv
L1-03 Mtr OH Alarm Sel Operation when the motor
temperature analog input
exceeds teh OH3 alarm level.
(1.17V) (H3-05 or 09 = E) 0-4 3 Adv
0 Decel to Stop (Alarm)
1 Coast to Stop (Alarm)
2 Fast Stop by B5-08 (Alarm)
3 Alarm Only (OH3 Flashes)
4 Stop by B3-03 Method
(Alarm)
L1-04 Mtr OH Fault Sel Operation when the motor
temperature analog input
exceeds the OH4 fault level.
(2.34V) (H3-05 or 09 = E) 0-2 2 Adv
0 Decel to Stop
1 Coast to Stop
2 Fast Stop by B5-08
L1-05 Mtr Temp Filter Motor temperature analog
input filter time constant 0.00-10.00 sec 0.20 Adv