Zenit MIXER Serie Manuel D'installation Et D'utilisation page 30

Safety, Installation and Operations Manual – Translation of original instructions
5. ELECTRICAL CONNECTIONS
5.1 General safety precautions
All the procedures involved in connecting the unit to the electrical mains must be carried out by a skilled electrician in accordance with the relevant
regulation.
The degree of protection (IP code) of the electrical panel must be suitable for the installation environment.
Incorrect electrical connections may cause fires and an electrocution hazard, or the risk of damage to the product.
• Make sure that the electrical panel is disconnected from the power supply and that it cannot be accidentally energized.
• Make sure that electrical protection measures have been adopted (e.g. ground connection, residual current devices, etc.) in accordance with all
relevant local and/or national regulations, laws and standards and that the skilled electrician has certified that the system is operating correctly.
• Check that the insulation resistance of the motor is 20 Mohm minimum (reference value based on new mixer).
• Make sure that the power supply line voltage and frequency are as stated on the dataplate and that the power absorption of the mixer is below
the maximum current the system is able to deliver.
• The maximum voltage variation allowed for rated value is ± 5%. Voltage imbalance between phases: max 2%.
• The fuses and protective cut-outs must be of suitable rating for the system's characteristics.
• Protect the mixer motor using an overload cut-out suitable for the electrical data provided on the dataplate.
• The electrical operation and safety of ZENIT mixers are guaranteed for the configuration supplied by the manufacturer: any changes (e.g. addi-
EN
tion of extra lengths of cable to the original power lead) may cause a deterioration in the mixer's characteristics.
5.2 Wiring
• To avoid short circuit, make sure that the electrical cables are not damaged in any way and the ends have not been exposed to dampness and/
or immersed in water. Contact an Authorized Zenit Service Center for replacement.
• Do not underestimate the problems caused by voltage drops.
Secure and mechanically protect the electric cables so that they cannot be twisted, torn and/or crushed.
The ends of the power supply cable must be connected to an electric panel certified for use in potentially explosive atmospheres
if it is installed in a hazardous area.
5.3 Operation by variable frequency drive (VFD)
The three-phase motors are also able to be powered by inverter type "PWM – Constant Torque (U/F=constant)". Set the frequency converter U/f
ratio according to the motor data.
Ex models may never, without exception, be operated using a frequency greater than the rated value indicated on the dataplate
as this may cause motor overload. The lowest frequency must be set so that it does not fall below 30 Hz.
Make sure that the rated current specified on the type plate is not exceeded after starting the motor. The maximum number of
starts according to the motor datasheet may not be exceeded.
The thermal protection of the motor must be connected.
5.4 Ground connection
• Make sure that the ground system and differential security breaker are present and in good working order.
• Check that the ground conductor is about 150 mm longer than the other conductors so that it will be the last to become disconnected from the
electrical panel in the event of accidental tugs.
The predisposition for the connection of the external earth conductor accepts cables with a cross-sectional area of at least 4 mm².
Do not connect the ground wire to a gas pipe, water pipe, lightening rod, or telephone ground wire. Improper grounding could
cause electrical shock.
On -Ex models, make sure that an external earth conductor (yellow and green, with cross section at least of 4 mm²) is connected
to the external earth terminal on the mixer using a secure cable clamp. Clean the surface of the externa earth connection and
mount the cable clamp.
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ZMD05_
ZMD06_ - ZMD07_ - ZMD08_
ZMR08_
better together