Grundfos CUE 150 Instrucciones De Instalación Y Funcionamiento página 33

If Active is selected, proceed as follows:
1. Close the isolating valve to create a no-flow condition.
2. Press OK to start the auto-tuning.
Operating conditions for the stop function
It is only possible to use the constant level stop function if the
system incorporates a level sensor, and all valves can be closed.
Description
The stop function is used for changing between on/off operation
at low flow and continuous operation at high flow.
Start level
ΔH
Stop level
Fig. 41 Constant level with stop function. Difference between
start and stop levels (ΔH)
Low flow can be detected in two different ways:
1. With the built-in low-flow detection function.
2. With a flow switch connected to a digital input.
1. Low-flow detection function
The built-in low-flow detection is based on the measurement of
speed and power.
When low flow is detected, the pump will stop. When the level has
reached the start level, the pump will start again. If there is still no
flow, the pump will reach the stop level and stop. If there is flow,
the pump will continue operating according to the setpoint.
2. Low-flow detection with flow switch
When the digital input is activated because of low flow, the speed
will be increased until the stop level (actual setpoint – 0.5 x ΔH) is
reached, and the pump will stop. When the level has reached the
start level, the pump will start again. If there is still no flow, the
pump will reach the stop level and stop. If there is flow, the pump
will continue operating according to the setpoint.
10.7.12 Sensor 1 (3.15)
Setting of sensor 1 connected to terminal 54. This is the feedback
sensor.
Select among the following values:
• Sensor output signal:
0-20 mA
4-20 mA.
• Unit of measurement of sensor:
3
bar, mbar, m, kPa, psi, ft, m
• Sensor measuring range.
3
/h, m /s, l/s, gpm, °C, °F, %.
10.7.13 Sensor 2 (3.16)
Setting of sensor 2 connected to an MCB 114 sensor input
module.
Select among the following values:
• Sensor output signal:
0-20 mA
4-20 mA.
• Unit of measurement of sensor:
3
bar, mbar, m, kPa, psi, ft, m
• Sensor measuring range:
0-100 %.
10.7.14 Duty/standby (3.17)
Settings
The duty/standby function can be set to these values:
• Active
• Not active.
Activate the duty/standby function as follows:
1. Connect one of the pumps to the mains supply.
Set the duty/standby function to Not active.
Make the necessary settings in menu OPERATION and
INSTALLATION.
2. Set the operating mode to Stop in menu OPERATION.
3. Connect the other pump to the mains supply.
Make the necessary settings in menu OPERATION and
INSTALLATION.
Set the duty/standby function to Active.
The running pump will search for the other pump and
automatically set the duty/standby function of this pump to Active.
If it cannot find the other pump, a fault will be indicated.
The two pumps must be connected electrically
Note via the GENIbus, and nothing else must be
connected on the GENIbus.
The duty/standby function applies to two pumps connected in
parallel and controlled via GENIbus. Each pump must be
connected to its own CUE and sensor.
The primary targets of the function is the following:
• To start the standby pump if the duty pump is stopped due to
an alarm.
• To alternate the pumps at least every 24 hours.
3
/h, m /s, l/s, gpm, °C, °F, %.
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