Hitachi X200 Series instruction manual Ctrl TRQ, 2CTRL TRQ

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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 specifications.

The following table shows the methods of torque control selection.

V	A045=100
100%
80%
	A045=80
0
fbase	fmax

Configuring Parameters

		“A” Function		Run		Defaults
Func.	Name /		Description	Mode -FE -FU				Units
Code	SRW Display			Edit	(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 motor				00		00	%
	2VBst Slct	MN
A042	Manual torque boost value		Can set boost starting torque	9	1.8		1.8	%
			between 0 and 20% above normal
	V-Bst V	0005.0%	V/f curve,
A242	Manual torque boost value,		range is 0.0 to 20.0%	9	0.0		0.0	%
	2nd motor
	2VBst V	0005.0%
A043	Manual torque boost		Sets the frequency of the V/f	9	10.0		10.0	%
	frequency adjustment		breakpoint A in graph (top of
			previous page) for torque boost,
	M-Bst F	0003.0%
			range is 0.0 to 50.0%
A243	Manual torque boost			9	0.0		0.0	%
	frequency adjustment,
	2nd motor
	2MBst F	0000.0%
A044	V/f characteristic curve		Two available V/f curves;		00		00	−
			00…Constant torque
	CTRL	C-TRQ
			01…Reduced torque
A244	V/f characteristic curve,				00		00	−
			06…Reduced torque1
	2nd motor
	2CTRL	C-TRQ
A045	V/f gain setting		Sets voltage gain of the inverter,	9	100.		100.	%
	V-Gain	00100%	range is 20. to 100.%
A245	V/f gain setting,			9	100.		100.	%
	2nd motor
	2V-Gain	00100%

Drive