8
The unit is equipped with all those technical arrangements required to ensure a good functioning
under normal situations installation.
The control system has a entry-filter, also have a current overload protection which guarantees
absolute protection when the Inverter is combined with motors that not exceed the maximum power.
For EMC is good that the power wires of control panel and motor power wires (when the motor are
separated from the inverter) are shielded type (or armoured) with individual conductors of appropriate
section (current density <= 5 A/mm2). These cables must be the minimum length necessary. The
screen conductor must be connected to the ground by both sides. On motor use the metal case for
connection to the ground of the screen.
To avoid loops that can create mass disturbances radiated (antenna effect), the motor operated by
the frequency converter must be connected on the ground individually, always with a low-impedance
using the metallic box of the machine.
The wires from power supply to frequency converter and wires from frequency converter – motor (if
the motor is separated to the Inverter) must be spaced as much as possible, not to create loops, not
make them run parallel less than 50 cm.
Don’t observe these conditions could cancel completely or partially the effect of the filter integrated.
4.5 Access to the electronic board
In case is necessary to change damaged cables, pressure transducer or to add the float switch
contact, you need to open the Inverter case.
The operations of a component for the inverter must be performed only by experienced
personnel qualified by the manufacturer, using only original spare parts supplied by the
manufacturer.
Any action with open box of the Inverter must be made after at least 2 minutes after
open line with appropriate switch or the physical separation from the power supply
cable;
In case of failure to one of the cables or the pressure transducer, for the replacement of that should
be opened by unscrewing the inverter cover the N° 12 screws in the back on the heat sink. For the
extraction of a cable, unscrew the three screws that close the cable triangular plate. Remember to
always replace the O-ring seal on the cable under the plate. To connect the cables in the appropriate
terminals follow the pattern of connections in the electronic board below (fig. 10):
Inverter Power supply cable: contact 220Vac + GND (J4)
Pressure transducer with 4-20 mA output: contact +Vcc, S;
Float switch enable: contact ENABLE, 0V (J5);
Motor ON output signal: Contact MOTOR ON, 0V (J5 - closed when the motor is ON, max. 30V,
3mA)
4.6 Connecting the float contact or other NC contact
To connect an enable Normally Closed contact use the poles 2 (Enable) and 5 (common) of J5 (fig.
10). When the contact open, the Inverter stop the pump; when the contact close, the pump may re-
start at previous working condition.
For the connection of the float switch contact you need to change the three poles cable of the sensor
with a four poles cable, passing on the same central exit of the transducer cable.
The new connections of pressure transducer and float switch contact must be done
out of the Inverter box, protecting them to humidity, water and dust. Do not practice
others holes to the Inverter case to avoid damages or decrease of the protection and
insulation grade and interruption in anticipation of the guarantee.
