Pump Controllers - Grundfos SL1 Instrucciones De Instalación Y Funcionamiento

8.2 Pump controllers

SL1 and SLV pumps can be connected to a separate Grundfos
Dedicated Controls for level control. Dedicated Controls are
available as accessories:
• type DC for one-pump installations
• type DCD for two-pump installations.
The Dedicated Controls system starts/stops the SL1 and SLV
pumps by means of one of the following transmitters:
• float switches
• pressure sensors
• ultrasonic sensors.
Furthermore, it is possible to control the water level by both float
switches and an analog pressure sensor or ultrasonic sensor.
Optionally, the controller can control a mixer. The Dedicated
Controls system can be extended with an IO 111 module per
pump (for SL1 and SLV pumps with built-in sensor).
When installing the level switches, observe the following points:
• To prevent air intake and vibrations install the stop level
switch in such a way that the pump is stopped before the
liquid level is lowered below the top of the cable entry.
• In tanks with one pump, install the start level switch in such a
way that the pump is started at the required level; however,
the pump must always be started before the liquid level
reaches the bottom inlet pipe to the tank.
• In tanks with two pumps, the start level switch for pump 2
must start the pump before the liquid level reaches the bottom
inlet pipe to the tank, and the start level switch for pump 1
must start this pump correspondingly earlier.
• If installed, always install the high-level alarm switch about
4" (100 mm) above the start level switch; however, the alarm
must always be given before the liquid level reaches the
bottom inlet pipe to the tank.
For further information, see the installation and operating
instructions for the pump controller selected.
Warning
FM
The pump must not run dry.
An additional level switch must be installed to
ensure that the pump is stopped in case the stop
level switch is not operating.
The pump must be stopped when the liquid level
reaches the top of the cable entry.
Float switches used in potentially explosive
environments must be approved for this
application. They must be connected to the
Grundfos Dedicated controls, DC or DCD, via an
intrinsically safe barrier to ensure a safe circuit.
18
Min. 4 Inch (100 mm)
Fig. 11 Start and stop levels
Make sure that the effective volume of the tank does not become
so low that the number of starts per hour exceeds the maximum
permissible number. See section 9.2 Operating modes.
Alarm
Start
Stop S1 operation
Stop S3 operation