Grundfos VLSE, Инструкция по установке и эксплуатации

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lish (US)
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22.2 Digital input
By means of the , one of the following functions can be selected
for the digital input:
• Normal duty
• Min. curve
• Max. curve
• External fault
• Flow switch
• Dry running.
Functional diagram: Input for digital function
23. External setpoint signal
The setpoint can be remote-set by connecting an analogue signal
transmitter to the input for the setpoint signal (terminal 4).
Fig. 39 Actual setpoint as a product (multiplied value) of
setpoint and external setpoint
Select the actual external signal, 0-10 V, 0-20 mA, 4-20 mA, via
the R100. See section
19.3.3 External setpoint on page 26 .
If control mode uncontrolled is selected by means of the R100,
the pump can be controlled by any controller.
In control mode controlled , the setpoint can be set externally
within the range from the lower value of the sensor measuring
range to the setpoint set on the pump or by means of the R100.
Fig. 40 Relation between the actual setpoint and the external
setpoint signal in control mode controlled
Example: At a sensor
min
value of 0 psi, a setpoint set of 50 psi
and an external setpoint of 80 % (an 8 V analog signal to
Terminal 4 if using an analog signal of 0-10 V), the actual
setpoint will be as follows:
In control mode uncontrolled , the setpoint can be set externally
within the range from the min. curve to the setpoint set on the
pump or by means of the R100. Typically the setpoint is set to
100 % when the control mode is uncontrolled (see section
19.5 Typical display settings for analog-input E-pumps on
page 33 ).
Fig. 41 Relation between the actual setpoint and the external
setpoint signal in control mode uncontrolled
Digital function
(terminals 1 and 9) (terminals 9 and 10) (terminals 9 and 11)
Normal duty
Min. curve
Max. curve
External fault
Flow switch
Dry running
TM0
3
8
60
1 2
0
0
7
Q
H
Q
H
Q
H
Q
H
5 s
delay
Q
H
5 s
5 s
delay
Q
H
Setpoint
External setpoint
Actual setpoint
T
M
02
8
9
8
8
13
04
Actual
setpoint
= (setpoint - sensor
min
) x %
external setpoint
+ sensor
min
= (50 - 0) x 80 % + 0
= 40 psi
TM
02
89
8
8
13
04
0 10 V
0 20 mA
4 20 mA
Actual setpoint
Sensor
max
Setpoint set by means of
control panel, or PC Tool
E-products
Sensor
min
External setpoint signal
Actual
setpoint
0 10 V
0 20 mA
4 20 mA
Actual setpoint
Max
curve
Setpoint set by means of
control panel, R100 or PC Tool
E-products
Min
curve
External setpoint signal
Actual
setpoint