5. ELECTRICAL CONNECTIONS
Always switch off the mains power supply before working on the electrical or
mechanical part of the system. Before opening the equipment, wait at least 10
minutes after disconnecting it from the power supply. The capacitor of the direct
current intermediate circuit remains charged with dangerously high voltage even
after the mains power has been turned off.
Only firmly cabled mains connections are admissible. The appliance must be earthed
(IEC 536 class 1, NEC and other applicable standards).
Ensure that the voltage and frequency on the data plate of the MCE-55/C are the same
as those of the power mains.
5.1
Connection to the Power Supply Line
The connection between the three-phase power supply line and the MCE-55/C must be made with a 4-core
cable (3 phases + earth). The characteristics of the power supply must satisfy the indications in Table 1.
The input terminals are the ones marked with the words LINE RST and with an arrow entering the
terminals, see Figure 1.
The maximum section accepted by the input and output terminals is 6 mm².
The external diameter of the input and output cables accepted by the cable glands for correct tightness
varies from a minimum of 11 mm to a maximum of 17 mm.
The section, type and laying of the cables for supplying power to the inverter and connecting to the
electropump must be chosen according to the regulations in force. Table 2 supplies an indication on the
section of the cable to be used. The table refers to 4-core PVC cables (3 phases + earth) and gives the
recommended minimum section with relation to the current and the length of the cable.
The electropump current is generally specified on the motor data plate.
The supply current to the MCE-55/C may be assessed in general (allowing a safety margin) as 1/8 more than
the current absorbed by the pump.
Although the MCE-55/C has its own internal protections, it is still advisable to install a suitably sized thermal
magnetic circuit breaker.
ENGLISH
Figure 1: Electrical connections
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