Electrical Connections - FPS VR Serie Manual De Instrucciones

• The connection pipes must be suitable for the operating pressure and the pumped liquid; between the pipe
connections and the pump, proper seals should be inserted.
• The pipes should be properly supported (Fig. 6-1), without resting on the unit. Do not force the position of the
pipes by affixing them, using bolts, to the pump (see Fig. 12 for maximum forces and stresses applicable to
connections). Flexible hoses or expansion joints (Fig. 6-2) are necessary to avoid vibrations being transmitted
from the pump to the piping and vice-versa. To prevent air bubbles in the suction pipe, arrange it at an
inclination of no less than 2%. The diameter of the pipe should not be smaller than the diameter of the suction
vent and should be sealed. If the suction pipe is bigger, install an eccentric reducer (Fig. 6-6). If the pump is
above the liquid to be lifted (negative suction head pump Fig. 6-A) a foot valve should be fitted to the end of
the suction pipe (Fig. 6-3).
• The end of the suction pipe should be sufficiently immersed to prevent air entering the suction vortex (Fig. 6-7)
when the liquid is at minimum level. Suitably sized gate valves should be fitted to the suction pipes (Fig. 6-4)
and delivery pipes (Fig. 6-8) to regulate flow and to isolate the pump from the circuit in the case of inspection
and maintenance.
• Install a check valve (Fig. 6-5) to the delivery piping to prevent reflux and water hammers when the pump is
switched off.
• See Fig. 8A-B: pump connections size and bolt tightening torques.
WARNING: Depending on the temperature of the pumped liquid, the surfaces of the pump may reach high
temperatures. If deemed necessary, provide guards to avoid accidental contact.

5.4.2 Electrical Connections

WARNING: Low voltage machines are comprised of rotating, hazardous, live parts and sometimes also
hot surfaces.
WARNING: The installer sees to making the connection in compliance with current standards in force in
the country of installation.
Guidelines
WARNING: The following information is valid for the standard motor supplied with the pump. If
the pump alone is supplied and is coupled with a different motor, please refer to the relative
operation and maintenance manual. Protect the electric connections from excessively high
temperatures, vibrations, and shocks.
The power line must be equipped with:
• A short circuit protection device
• A residual current device less or equal to 30mA
• An overvoltage category III all-pole mains isolator in the power supply network according to current standards.
The electric control panel should:
• Be suited to the rated values of the pump to properly protect the motor
• Protect the motor from overheating (circuit breaker protection)
• Be equipped with a system to protect against dry running, which should be connected to the pressure switch,
level sensors, floats and other suitable devices. An inflow pressure switch is recommended if the pump is
connected to the water supply or level sensors/floats if the pump draws from a tank.
WARNING: The data regarding the power supply of the motor are shown on the nameplate of the
same. For more information about the operation and maintenance of the motor, refer to the
motor manual.
Before starting up the motor, check that the electrical supply is compatible with the characteristics of the same.
Wire the electric cable to the motor according to the diagram shown inside the cover of the terminal box. Check
that the earth cable is longer than the phase connections: If the power supply cables are pulled and detached from
their cable stay, the last one that should be disconnected is the earth cable. Make the connection ensuring there
is an effective earth circuit.
WARNING: Once the cables have been connected, replace the terminal box cover; failure to observe
these instructions may cause personal injury.
9