Omron VARISPEED E7 User Manual page 172

Setting Motor Protection Operation Time (L1-02)
Set the motor protection operation time in L1-02.
The motor protection operation time is the time for that the motor can handle a 150% overload when it was
running with the rated load before (i.e. operating temperature was reached before applying the 150% over-
load). Set the motor protection operation time in L1-02. The factory setting is 60 sec.
The following diagram shows an example of the characteristics of the electronic thermal protection operation
time (L1-02 = 1.0 min., operation at 50 Hz, general-purpose motor characteristics, when L1-01 is set to 1)
Operating time (min.)
Setting Precautions
If multiple motors are connected to one inverter, set parameter L1-01 to 0 (disabled). To protect each of the
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motors, use a control circuit that switches off the inverter output when one of the motors overheats.
With applications where the power supply is often turned ON and OFF, there is a risk that the motor cannot
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be protected even if this parameter has been set to 1 (enabled), because the thermal value will be reset after
inverter power supply switch off.
For safe overload tripping, set the value in parameter L1-02 to a low setting.
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Setting the Motor Overload Pre-Alarm
To enable the Motor overload pre-alarm enable the motor overload protection function (i.e., L1-01 must be set
to 1) and set H2-01 or H2-02 (multi-function output terminals M1-M2 and M3-M4 function selection) to 1F
(motor overload OL1 pre-alarm). If the electronic thermal value reaches minimum 90% of the overload detec-
tion level, the output terminal that has been set will be turned ON.
Cold start
Hot start
Motor current (%)
(E2-01 is set to 100%)
Fig 6.25 Motor Protection Operation Time
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