Hitachi CP-X200 －45, 45, Ovladstop OFF, Ladst LVL, B130, B131 Over-voltage LAD Stop Enable

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B130, B131: Over-voltage LAD Stop Enable

/Level – The over-voltage LADSTOP function monitors the DC bus voltage and actively changes the output frequency profile to maintain the DC bus voltage within settable limits. Although “LAD” refers to “linear acceleration / deceleration”, the inverter only “STOPs” the deceleration ramp so that regenerative voltage will not cause the DC bus to rise enough to cause an over-voltage trip event. Note that acceleration is not affected.

The graph at right shows an inverter output profile that starts deceleration to a stop. At two different points during the deceleration, regenerative voltage elevates the DC bus level, exceeding the LADSTOP threshold set by B131.

B130 = 01 OV LADSTOP = Enable

DC bus voltage

B131

0	t
Output	Stops decel
frequency
	Resumes decel
0	t

Set decel time (F003)

Actual decel time

When the Over-voltage LADSTOP feature is enabled by setting B130 = 01, the inverter										&RQ¿JXULQJ'ULYH Parameters
stops the deceleration ramp in each case until the DC bus level is again less than the
threshold value.
When using the Over-voltage LADSTOP feature, please note the following:
	ξ When the feature is enabled (B130 = 01), the actual deceleration is sometimes
	longer than the value set by parameters F003/F203.
	ξ The over-voltage LADSTOP feature does not operate by maintaining a constant
	DC bus voltage. So it is still possible to have an over-voltage trip event during
	extreme deceleration.
	ξ If B131 is set lower than the normal DC bus voltage (when not in decel) by
	mistake, or if the inverter’s input voltage increases enough, then the inverter will
	apply LADSTOP (if enabled) all the time. In this case, the inverter can accelerate
	and run the motor, but it cannot decelerate. If you are not sure that B131 > DC
	bus voltage, measure the DC bus voltage in your installation and verify that the
	B131 value is higher.
		“B” Function			Run		Defaults
Func.	Name /			Description	Mode	-FE		-FU	Units
Code	SRW Display				Edit	(EU)		(USA)
B130	Over-voltage LADSTOP		Pauses deceleration ramp when DC bus			00		00	
	enable		voltage rises above threshold level, in
			order to avoid over-voltage trip.
			00	Disable
	OVLADSTOP	OFF	01	Enable
B131	Over-voltage LADSTOP		Sets the threshold level for over-voltage		9	380/		380/	V
	level		LADSTOP. When the DC bus voltage is			760		760
			above the threshold value, the inverter
			stops deceleration until the DC bus
			voltage is less than the threshold
			setting again. Two voltage ranges with
			1V resolution:
			330 to 395V (200V class)
	LADST LVL 0	0380V	660 to 790V (400V class)