Burkert Type 8611 User Manual

Page 77

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77

FunctionsoftheConfigurationLevel

Overview of the valve opening times of the Bürkert process valves depending on the actuator size and pilot
pressure:

actuator size [dn]

pilot pressure

Opening time for valve [s]

closing time for valve [s]

50

6

2

2

5
4

63

6

2

3

5

3

4

4

80

6

4

5

5

5

Table 28:

Valve opening times for Bürkert process valves

0 – 10 - flow-rate control with motor valve and 0 - 10 V control
(For schematic representation see “Figure 37: Example of a flow-rate control with 0 - 10 V control”)

Technical description:

• Motor ball valve with 0 - 10 V control.

• The max. process value change between closed and open position of the valve amounts to 20 l/min.

• The control range of the valve is not restricted:

VALV, MIN = 0, MAX = 10

(see chapter “12.17. VALV - Test function and setting of the control range”).

• According to the manufacturer, the opening and closing time are 90 s each.

Calculation for K

p1

:

100 %
20 l/min

K

p1

=

= 5 % (l/min)

·

100

The opening or closing time for the valve is taken into consideration by the reset time T

n

. As start value for T

n

about 60 - 70 % of the valve opening time can be taken.

2P – T

- Temperature control with open/closed valve

(For schematic representation see “Figure 39: Example of a 2-state temperature control with open/closed valve”)

Technical description:

• Solenoid valve.

• The process value change between closed and continuously opened position of the valve amounts to 10 °C.

• The time for the temperature change amounts to 20 s.

Calculation for K

p1

:

100 %
10 °C

K

p1

=

= 10 % °C

• The reset time T

n

can be set between 15 - 20 s.

• With the controller cycle time T

reg

the switching frequency of the valve can be influenced.

Recommendation: T

reg

= 0.5 - 0.25 T

n

english

Type 8611