Siemens SINUMERIK 840D Description Of Functions page 129

04.00
02.99
5487 NEG_DUAL_GAIN_COMP_S_FLOW
Knee-point compensation neg. flow saturation
Unit: Default:
% 100.0
5488 NEG_DUAL_GAIN_COMP_S_VOL T
Knee-point compensation neg. voltage saturation
Unit: Default:
% 100.0
Offset
5470 OFFSET_COMPENSATION
Offset compensation
Unit: Default:
– 0
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SINUMERIK 840D/SIMODRIVE 611 digital Descr. of Functions HLA Module (FBHLA) – 04.00 Edition
Minimum: Maximum:
0.2 100.0
Minimum: Maximum:
0.2 100.0
To calculate the inverse characteristic, the beginning of a saturation range with
parabolic rounding in the positive quadrant of the valve characteristic is defined
in MD 5485 and MD 5486 and in the negative quadrant with MD 5487 and MD
5488.
The positive and negative valve flows at the beginning of the saturation region
referred to rated flow (MD 5107) are entered in MD 5485 and MD 5487 respec-
tively.
The positive and negative valve voltages referred to valve rated voltage (MD
5109) are entered in MD 5486 and MD 5488 respectively.
The saturation region is compensated by a root characteristic such that the in-
tersection point lies on a continuous tangent and the characteristic ends at the
point (100%, 100%).
With default 100% set in MD 5485 and MD 5486 or in MD 5487 and
MD 5488, there is no saturation region in the positive or negative quadrant.
For more detailed explanation, see also Section 2.3.1 and Appendix A.
Minimum: Maximum:
–4000 4000
Since the valves are operated under analog control, an offset voltage of the D/A
converter or valve amplifier may cause a zero point error and thus a position
deviation (if no I-action component has been activated). By adding a compensa-
tion value, the offset error can be largely eliminated.
An automatic offset adjustment can be initiated with MD 5650 (see Section
3.9.2).
Note
When closed-loop force control is active (MD 5241), offset compensation is
absolutely necessary because the I component of the velocity controller is de-
activated with closed-loop force control.
4 Firmware Drive Functions
4.5 Output of manipulated variables
Cross ref.: –
Relevant for: Protection level:
HLA 3/3
Data type: Effective:
FLOAT Immediately
Cross ref.: –
Relevant for: Protection level:
HLA 3/3
Data type: Effective:
FLOAT Immediately
Cross ref.: –
Relevant for: Protection level:
HLA 3/3
Data type: Effective:
WORD Immediately
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