Hitachi L200 Overload Restriction

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“B” Group: Fine Tuning Functions

Overload Restriction

If the inverter’s output current exceeds a preset current level you specify during acceleration or constant speed, the overload restriction feature automatically reduces the output frequency to restrict the overload. This feature does not generate an alarm or trip event. You can instruct the inverter to apply overload restriction only during constant speed, thus allowing higher currents for acceleration. Or, you may use the same threshold for both acceleration and constant speed.

When the inverter detects an overload, it must decelerate the motor to reduce the current until it is less than the threshold.

You can choose the rate of deceleration that the inverter uses to lower the output current.

Motor

Current

Restriction area

B022

0

t

Output

frequency

0
		t
	B023

Configuring ParametersDrive			“B” Function		Run		Defaults
	Func.	Name /		Description	Mode	–FEF	–FU	Units
					Edit
	Code	SRW Display				(EU)	(USA)
	B021	Overload restriction		Select the operating mode	✘	01	01	—
		operation mode		during overload conditions,
				three options, option codes:
		OL Mode	ON
				00... Disabled
				01... Enabled for acceleration
				and constant speed
				02... Enabled for constant
				speed only
	B022	Overload restriction		Sets the level for overload	✘	Rated current x		A
		setting		restriction, between 20% and		1.5
				150% of the rated current of
		OL LVL	002.40A
				the inverter, setting resolution
				is 1% of rated current
	B023	Deceleration rate at		Sets the deceleration rate when	✘	1.0	30.0	sec.
		overload restriction		inverter detects overload, range
				is 0.1 to 30.0, resolution is 0.1.
		OL Cnst	0001.0s