pumpa BLUE Series - Motor Safety and Protection; Grounding; Three-Phase Connection

EN
28
The user must ensure that the water level in the well (borehole) is sufficiently high. In the event that it is not possible to
guarantee a sufficient water level, it is necessary to install, for example, an electrode blocking device to block the
pump from running dry.
5.1 Motor safety and protection
• Make sure to install an external mains switch so that the system can be switched off completely at any time.
• Provide installation of protection for all phases.
5.2 Grounding
• When sizing the grounding, take into account the rated power of the motor.
• The motor must be grounded.
Ensure good contact of the protective conductor terminal.
5.3 Three-phase connection
Connect the motor with its direction of rotation according to the direction marked on the unit. This
connection is characterised by the usual circuit with the field rotating clockwise and counterclockwise for
the motor shaft.
5.3.1 Checking the direction of rotation
To check the direction of rotation, look at the arrow on the pump, then switch on the pump for a maximum of 5
seconds. It must rotate in the direction of the arrow.
In case the pump spins in the opposite direction, switch the 2 phases between each other.
5.4 Lightning protection
Surge protection (lightning surge protection) must be installed in the control cabinet on all input phases).
5.5 Insulation resistance measurement
Make this measurement before start-up and during the start-up of assembled units at the location
of use.
The motor is OK if its insulation resistance at 20 °C is at least the following:
Minimum insulation resistance with extension cable:
• for a new motor > 4 MΩ
• for a used motor > 1 MΩ
Minimum insulation resistance without extension cable:
• for a new motor > 400 MΩ
• for a used motor > 20 MΩ