Grundfos VLSE, Инструкция по установке и эксплуатации

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29
English (US)
Diaphragm tank
The stop function requires a diaphragm tank of a certain minimum
size. The tank must be installed immediately after the pump and
the precharge pressure must be 0.7 x actual setpoint.
Recommended diaphragm tank size:
If a diaphragm tank of the above size is installed in the system,
the factory setting of
˂
H is the correct setting.
If the tank installed is too small, the pump will start and stop too
often. This can be remedied by increasing
˂
H.
19.3.9 Flow limit for the stop function
In order to set at which flow rate the system is to go from
continuous operation at constant pressure to start/stop operation,
select among these four values of which three are preconfigured
flow limits:
• Low
• Normal
• High
• Custom.
The default setting of the pump is Normal, representing approx.
10 % of the rated flow rate of the pump.
If a lower flow limit than normal is desired or the tank size is
smaller than recommended, select Low.
If a higher flow than normal is wanted or a large tank is used, set
the limit to High.
The value Custom can be seen in R100 but it can only be set by
means of the PC Tool E-products. Custom is for customized set-
up and optimizing to the process.
Fig. 31 Three preconfigured flow limits, Low, Normal and High
19.3.10 Sensor
The setting of the sensor is only relevant in the case of controlled
operation.
Select among the following values:
• Sensor output signal
0-10 V
0-20 mA
4-20 mA,
• Unit of measurement of sensor:
bar, mbar, m, kPa, psi, ft, m
3
/h, m
3
/s, l/s, gpm, °C, °F, %,
• Sensor measuring range.
Rated flow of
pump
[gpm (m
3
/h)]
CRE pump
Typical diaphragm
tank size
[gal (litre)]
0-26
(0 - 5.9)
1s, 1, 3 2 (7.6)
27-105
(6.1 - 23.8)
5, 10, 15 4.4 (16.7)
106-176
(24.2 - 40)
20, 32 14 (53.0)
177-308
(40.2 - 70.0)
45 34 (128.7)
309-440
(70.2 - 99.9)
64, 90 62 (234.7)
441-750
(100-170)
120, 150 86 (325.5)
1RWH
1RWH
Flow limit for the stop function only works if the
system is not set up for flow switch.
TM
03
90
6
0
33
07
Without sensor
(uncontrolled) With pressure sensor
(controlled)
˂
H
Low
High
Normal