6. Electrical connection
E l e c t r i c a l c o n n e c t i o n m u s t b e c a r r i e d o u t
only by a qualified electrician in accordance
with local regulations.
Follow all safety standards.
The unit must be properly earthed (grounded).
Connect the earthing (grounding) conductor to the termi-
nal with the marking.
Compare the frequency and mains voltage with the name-
plate motor data and connect the supply conductors to
the terminals in accordance with the corresponding di-
agram inside the terminal box.
ATTENTION: never allow washers or other metal
parts to fall into the internal cable opening between
the terminal box and stator.
If this occurs, dismantle the motor to recover the object
which has fallen inside.
ATTENTION
: with motor power rating ≥ 5.5 kW avoid di-
rect starting. Provide a control panel with star-delta start-
ing or an other starting device.
The motors with supply current directly
switched by thermally sensitive switches
can start automatically.
Install a
device for disconnection from the mains
(switch) with a contact separation of at least 3 mm in all
poles.
Install a suitable overload cutout in accordance with the
rated current.
Single-phase
MXV-BM
pumps are supplied with a capaci-
tor connected to the terminals and (for 220-240 V - 50 Hz)
with an incorporated thermal protector.
Electrical diagram (only for Calpeda motors)
MXV-B 25,32,40
MXV-B 50
MXV(L), MXV(L)4 25,32,40
MXV(L), MXV(L)4 50-65-80
Refer to any other instructions (if supplied) for use of the
motor.
7. Starting
7.1. Preliminary checks
Make sure the coupling with the pump shaft turns freely
when rotated by hand (see
section 4.
).
Make sure the screws (64.25) of the coupling are tight-
ened (see
section 10.2.
).
Make sure the coupling guard (32.30) is fas-
tened on the lantern bracket.
For
MXV-B
Make sure the shaft turns freely when rotated
by hand.
For this purpose use the screwdriver notch on the shaft
end ventilation side.
7.2. Filling
ATTENTION: never run the pump dry, not even for a
short trial run.
Start the pump after filling it completely with liquid.
When the pump is located above the water level
(suc-
tion lift operation,
fig. 2A
) or with a positive suction head
which is too low (less than 1 m) to open the non-return
valve, fill the suction pipe and the pump through the prim-
ing hole (1) (
fig. 3
).
To facilitate this operation use a flexible tube (or elbow)
and a funnel.
MXV-B, MXV(L) 25-32-48, MXV(L)4 25-32-48
During filling, the needle screw (14.17) in the drainage
plug (14.12) must be kept loose so as to allow a free
passage between the pressure chamber and the suction
chamber (Fig.3a).
MXV(L) 50-65-80, MXV(L)4 50-65-80
In the case of vertical installation, remove the plug (2)
during the filling operation to vent the suction side. After
the liquid has been released, replace the plug (2). Pro-
ceed with filling until the liquid spills out of the venting
hole (1 ) in the upper cover. Top up until the pump is com-
pletely vented before replacing the plugs (1). In the case
of horizontal installation, fill and vent through the holes
(1) in the pump casing (14.00).
When the liquid level on the suction side is above the
pump
(inflow under positive suction head,
fig. 2B
), fill the
pump by slowly and completely opening the inflow gate
valve while keeping the delivery gate valve and air vent
holes (1), (2) (
fig.3
) open to release the air.
During filling, keep the air vent holes (1)(2)
open only if the inflowing liquid presents no
possible danger on account of its nature, tem-
perature or pressure.
Only for MXV(L)50-65-80, MXV(L)4 50-65-80, If neces-
sary, install joints with a tap/valve device to holes 1 and 2,
to control the outflow of the liquid and its direction of flow.
With a delivery pipe arranged horizontally, or lower than
the pump, keep the delivery gate valve closed during
the filling operation.
(3)
(1) (2)
2)
1)
(3)
(3)
4.93.215
Fig.3 (1) Filling and air vent
(2) Suction side air vent
(3) Draining
13
W2 U2 V2
U1 V1 W1
L3 L2 L1
W2 U2 V2
U1 V1 W1
L3 L2 L1
W2 U2 V2
U1 V1 W1
L1 L2 L3
W2 U2 V2
U1 V1 W1
L1 L2 L3
Fig. 3a
Filling:
internal passage open
Fig. 3b
Operating:
internal passage closed
4.93.008
4.93.306
14.12
(1)
14.17
Filling and
air vent 14.04
MXV-B, MXV 25-32-48
Fig. 3c Drainage
MXV.. 50-65-80
