Hitachi L200 NOTE:, Voltage Gain –, The following table shows the methods of torque control selection

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“A” Group: Standard Functions

Be aware that running the motor at a low speed for a long time can cause motor overheating. This is particularly true when manual torque boost is ON, or if the motor relies on a built-in fan for cooling.

NOTE: Manual torque boost applies only to constant torque (A044=00) and variable torque (A044=01) V/f control.

Voltage Gain – Using parameter A045 you can modify the voltage gain of the inverter (see graph at right). This is specified as a percentage of the full scale output voltage. The gain can be set from 20% to 100%. It should be adjusted in accordance with the motor specifi- cations.

V 100%

20%

Voltage Gain

A045

The following table shows the methods of torque control selection.

0 Hz

Configuring Drive Parameters

		“A” Function			Run		Defaults
Func.	Name /			Description	Mode	–FEF	–FU	Units
					Edit
Code	SRW Display					(EU)	(USA)
A041	Torque boost select			Two options:	✔	00	00	%
				00... Manual torque boost
	V-Bst Slct		MN
				01... Automatic torque boost
A241	Torque boost select, 2nd			Two options:	✔	00	00	%
	motor			00... Manual torque boost
				01... Automatic torque boost
	2VBst Slct		MN
A042	Manual torque boost			Can boost starting torque	✔	5.0	5.0	%
	value			between 0 and 20% above
				normal V/f curve,
	V-Bst V	0005.0%
				range is 0.0 to 20.0%
A242	Manual torque boost			Can boost starting torque	✔	0.0	0.0	%
	value, 2nd motor			between 0 and 20% above
				normal V/f curve,
	2VBst V	0000.0%
				range is 0.0 to 20.0%
A043	Manual torque boost			Sets the frequency of the V/f	✔	3.0	3.0	%
	frequency adjustment			breakpoint A in graph (top of
				previous page) for torque
	M-Bst F	0003.0%
				boost, range is 0.0 to 50.0%
A243	Manual torque boost			Sets the frequency of the V/f	✔	0.0	0.0	%
	frequency adjustment,			breakpoint A in graph (top of
	2nd motor			previous page) for torque
				boost, range is 0.0 to 50.0%
	2MBst F	0000.0%
A044	V/f characteristic curve			Two available V/f curves;	✘	02	02	—
	selection			three select codes:
				00... Constant torque
	CTRL	C-TRQ
				01... Reduced torque