Resistance Measurement - Lorentz PSk2-7 Manuel D'installation Et De Fonctionnement

40 Pump Installation
Centrifugal Pumps:
Check of rotation direction after submersible pump instal-
lation:
(1) Connect the pump to the controller and power supply.
(2) Start the pump and check the delivered flow rate.
(3) Stop the pump, disconnect the power supply and
change two of the three phase leads
(4) Start the pump again and check the delivered flow.
(5) Stop the pump, disconnect the power supply and com-
pare the flow rates from point 2 and 4. The wiring with
the better flow rate has the right rotational direction.
Figure 21: Example LORENTZ PSk2 submersible pumps

9.2.2 Resistance measurement

We recommend checking the winding and insulation resist-
ance before connecting the pump to the controller. For a
submersible pump these measurements should be done
BEFORE lowering the pump into the well.
WARNING – Before starting any work on
the pump system, make sure that the
electricity supply has been switched off
and that it cannot be accidentally switched
on!
To measure the winding and insulation resistance discon-
nect all motor leads from the controller. A good quality
multimeter is necessary to measure the phase-to-phase
resistance with an accurancy to the first decimal place. ("0.1
Ohms"). It is also adviseable to consider the resistance of
the multimeter leads when measuring very low values:
ƒ Hold the tips of the multimeter together and note the
value.
ƒ Always substract this value from your motor resistance
measurements!