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To avoid overloads on the pumps due to impurities or solid particles in the pumped
liquid, the use of a filter in the suction line is strongly recommended. This filter has to be
regularly checked to avoid obstruction.
If unacceptable working conditions are revealed, the pump has to be automatically
stopped and checked.
The pump is equipped with a conductive ring and so with an accurate ground connection
of the ring there can’t be unwanted electrostatic charges, sources of explosion trigger.
Pumps supplied for ATEX zone 2 must be coupled to suitable Ex-proof motors.
2.8 Motor Connection
Check that the tension and frequency printed on the label of the motor correspond to
those of the electric system to be used.
Don’t connect the electric motor directly to the main system but protect the dedicated
system with a suitable main switch with adequate safety protections against overloads.
The electric connections have to be always carried out by an expert qualified electrician.
The motors have to be supplied with three-phase tensions or if required by the customer,
with mono phase tension. The type of connection of the three-phase motors can be Star
(Y) or Delta (Δ) according with the power supply 380 or 220 VAC (see picture 1).
Make sure that the sense of rotation of the motor is that specified on the pump head and
eventually indicated by a sticker arrow on the motor fan; to change the sense of rotation
it’s sufficient to change two of the three entering line (E.g . L1 with L2) in three-phase
motors.
Picture 1