Setting The Control Mode - Wilo Stratos GIGA Einbau- Und Betriebsanleitung

10.8

Setting the control mode

H
H
max
1 H
s
s
H
2
s
H
min
H
H
H
max
H
1
s
H
2
s
H
min
Fig. 32: Δp-c/Δp-v control
H
H
n
max
n
min
Fig. 33: Constant speed
Installation and operating instructions • Wilo-Stratos GIGA, Wilo-Stratos GIGA B • Ed.01/2023-05
• Make sure that the pump is completely filled up.
• Do not operate for too long with the volume flow being too low.
• Larger pumps require a minimum flow rate amount to operate properly.
• Operating against a closed shut-off device can lead to overheating in the centrifugal
chamber and to damage of the shaft seal.
• Ensure a continual flow to the pump with a sufficiently large NPSH.
• Prevent insufficient counter pressure leading to a motor overload.
• To avoid significant increases in motor temperature and excessive load on the pump,
coupling, motor, gaskets and bearings, perform no more than 10 switch-on procedures
per hour.
Twin-head pump operation
To ensure the standby pump is ready for operation, operate the standby pump every 24 h
at least once a week. See also section "Twin-head pump operation behaviour" and section
"Pump kick".
Δp-c/Δp-v control
Setting
Duty point on maximum
pump curve
Duty point within the control
range
Q
Setting range
Table 16: Δp-c/Δp-v control
Q
Q
Constant speed
"Constant speed" mode deactivates all other control modes. The speed of the pump is kept
to a constant value and set using the rotary knob. The speed range is dependent on the mo-
tor and pump type.
PID-Control
The PID controller used is a standard PID controller as described in the control engineering
literature.
The PID controller determines the difference between the measured actual value and the de-
n = const sired setpoint (control deviation). It attempts to match the actual value to the setpoint by
max
changing the pump speed via its output signal.
Q
The appropriate sensors make various controls possible (e.g. pressure, differential pressure,
Q
temperature or flow control). When selecting a sensor, pay attention to the electrical values
in the "Terminal assignment" table.
The control behaviour can be optimised by adjusting the P, I and D parameters.
The proportional component (P component) of the controller amplifies the controller's out-
put signal directly and linearly. The sign of the P term determines the controller's direction of
action.
The integral component (I component) of the controller integrates via the control deviation.
A constant deviation results in a linear amplification of the output signal until the setpoint is
reached. The I controller is an accurate but slow controller that results in no permanent con-
trol deviation.
The differential component (D component) of the controller does not react to the control
deviation, but only to its rate of change. This affects the rate at which the system responds.
Δp-c
Starting at the duty point,
draw towards the left. Read
setpoint H and set pump to
S
this value.
Starting at the duty point,
draw towards the left. Read
setpoint H and set pump to
S
this value.
H , H see pump curves
min max
(e.g. in data sheet)
NOTICE
Alternatively, you can also set the constant speed or the PID operation
mode.
en
Δp-v
Starting at the duty point,
draw towards the left. Read
setpoint H and set pump to
S
this value.
Move to max. pump curve
along control curve, then ho-
rizontally to the left, read off
setpoint H and set the pump
S
to this value.
H , H see pump curves
min max
(e.g. in data sheet)
127