317

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

%

 

 

 

 

 

00Manual torque boost

 

 

 

 

 

 

 

 

V-Bst Slct

MN

 

 

 

 

 

 

 

 

01Automatic 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

 

 

 

 

 

00Constant torque

 

 

 

 

 

 

 

 

CTRL

C-TRQ

 

 

 

 

 

 

 

 

01Reduced torque

 

 

 

 

 

 

 

A244

V/f characteristic curve,

 

00

 

00

 

 

06Reduced 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

Page 91
Image 91
Hitachi X200 Series instruction manual Ctrl TRQ, 2CTRL TRQ