Siemens SINUMERIK 840C User Manual

Page 232

Advertising
background image

09.95

6 NC Machine Data (NC MD), NC Setting Data (NC SD)

6.4 Axis-specific MD 1 (axial data 1)

Scaling factor maximum speed setpoint

260*

Default value

Lower input limit

Upper input limit

Units

8 000

1)

10 000

2)

9 000

3)

1
0
1

99 999 999

20 000
20 000

0.01 % of

max. setpoint

Active for all

channels of

mode groups

in STOP

Active:

for all channels of mode group in stop

The multgain factor is used to match the controlled system to the K

V

factor specified in

NC MD 252*. The multgain is a pure multiplier for the specified K

V

factor, and should be used

for precision digital tacho-generator matching in view of the very fine adjustment
capabilities.

Following the correct entry or matching of the multgain, the K

V

factor produced for the relevant

axis must correspond precisely to the specified value.

Note:

Matching of the actual K

V

factor via NC MD 252* (K

V

factor) is not to be recommended, as

different input values would be obtained for the various axes despite identical gain in the
position control loop.

Where U

max

is the speed setpoint voltage at maximum motor speed

Multgain = U

max

[mV]

If problems of precision or restrictions caused by input limits occur, the factors between MD
256* and 260* can be reduced or increased. See Section entitled ”Axis (Analog) and Spindle
Installation”. See MD 141 for digital drive.

Threshold value for drive errors

264*

Default value

Lower input limit

Upper input limit

Units

9 600

1)

12 000

2)

+0

0

15 000
20 000

VELO

0.01% of max.

motor speed

Active on
NC Stop

The specified setpoint speed is monitored; if it is too high (control loop and drive errors), alarm
156* is triggered.

The specified value must be greater than the highest maximum setpoint speed specified in NC
MD 268*.

Recommended value

Approx. 20 % higher than the value in NC MD 268*

See also Section entitled ”Axis (Analog) and Spindle Installation”.

_______

1)

Up to SW 2

2)

As from SW 3

3)

As from SW 4

©

Siemens AG 1992 All Rights Reserved 6FC5197- AA50

6–47

SINUMERIK 840C (IA)

Advertising
This manual is related to the following products: