Baelz Automatic 6490B - 3.6 Actuating time (t.P)

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Device manual 6490B / 6490B-y / 6590B
W. Bälz & Sohn GmbH & Co. Koepffstraße 5 D-74076 Heilbronn Telefon (07131) 1500-0 Telefax (07131) 1500-21
3.2 Proportional band Pb
Setting range: 1.0% to 999.9%
Proportional action of the PI(D) three-position step controller
3.2.1 Three-position controller
Pb = 0.0
tn > 0
Control action adjustable via dead band db
(see also 3.5 db)
3.3 Integral action time tn
Setting range: 1s to 2600s
Integral action of the PI(D) three-position
step controller
3.3.1 Two-position controller
tn = 0
Control action adjustable via dead band db
(see also 3.5 db)
3.4 Derivative action time td
Derivative action of the PID three-position step controller
Setting range: 1s to 255s
3.5 Dead band db
No actuating pulses if control deviation is smaller than db
Hysteresis: db/2
Setting range:
0 to 10th part of the scope of the measuring range
[phys. units]
0 to + scope of the measuring range [phys. units] at dP = 3
(see also 3.2.1 three-position controller
3.3.1 two-position controller)
3.6 Actuating time t.P
(Valve actuation time)
Setting range: 5s to 300s
Time to pass through the setting range 0% to 100% (stroke) at constant OPEN or CLOSE pulse
Setting the valve actuating time t.P has got a very important meaning. It has to be ascertained as
exact as possible for each valve and set to the controller. A bad valve actuating time causes a wrong
manipulated variable.
3.2.1 Three-position controller
3.3.1 Two-position controller
3.5 Dead band