GE MN-ValVue-v2-8-IOM Manuel de service télécharger pdf (Page 128)

100

101

ValVue Digital Communications Software Ver. 2.80

128

GE Oil & Gas

The Advanced Tuning Parameters dialog appears (Figure 106). Refer to Table 7 for

parameter descriptions.

Figure 106 Advanced Parameters Dialog

Table 7 Advanced Tuning Parameters

Tuning Parameter Description

Dead Zone When the valve position is within the setpoint +/- the dead zone, no additional posi-

tion control is performed. This value is normally 0%, however for high friction valves

(e.g. valves with graphite packing) a higher dead zone (%) helps avoid limit cycling

due to the stick/slip action of the valve. In these cases the dead zone chosen might

be 0.5% to 1%. Range: 0 and 5%.

Beta Beta is nonlinear gain factor, ranging from -9 to 9. When beta is 0, the position con-

troller gain is linear. Otherwise the gain is function of error. The larger the Beta, the

smaller the gain for small error. Typical values for a valve position controller is 7 or 8.

Position Compensation

Coefficient

The response of a valve is different when it is nearly closed than when it is nearly

open. The position compensation coefficient, a number between 2 and 20, allows

you to make adjustments to try to equalize the valve response. The normal value is 6.

Boost The boost field in the PID adjustments controls a supplemental pressure or boost to

speed up initial valve response. Valve response is the amount of time it takes for the

valve to go from setpoint to 100%

Stroke Time Amount of time in seconds required for the valve to be completely stroked.

1 2 ... 123 124 125 126 127 128 129 130 131 132 133 ... 659 660

Commentaires sur ces manuels

Pas de commentaire

GE MN-ValVue-v2-8-IOM Manuel de service Page 128

Commentaires sur ces manuels

Produits connexes et manuels pour Mesure, test et contrôle GE MN-ValVue-v2-8-IOM