Elettronica Santerno SINUS K, Руководство пользователя

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INSTALLATION
SINUS K
INSTRUCTIONS
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14.1.2. O
UTPUT
T
OROID
F
ILTERS
Ferrite is a simple radiofrequency filter. Ferrite cores are high-permeable ferromagnetic materials used to
weaken cable disturbance:
•
in case of three-phase conductors, all phases must go through ferrite;
• in case of single-phase conductors (or 2wire line) both phases must go through ferrite (incoming and
outcoming conductor cables that are to be filtered must go through ferrite).
14.1.3. C
ABINET
To prevent input and output of electromagnetic emissions to and from the cabinet, draw particular attention to
the cabinet doors, opening and cable paths.
A) Use a seam-welded metal frame ensuring electrical continuity.
Provide an unpainted, reference grounding support on the frame bottom. This steel sheet or metal grill is to be
connected to the metal frame, which is also connected to the ground mains of the equipment. All components
must be bolted directly to the grounding support.
B) Hinged parts or mobile parts (i.e. doors) must be made of metal and capable of restoring electrical
conductivity once closed.
C) Segregate cables bases on the type and intensity of electrical quantities and the type of devices which they
are connected to (components that may generate electromagnetic disturbance and components that are
particularly sensitive to disturbance):
- analog inputs and outputs: voltage reference and current reference
- sensors and measurement circuits (ATs and VTs) high sensitivity
- DC supply (10V, 24V)
low sensitivity - digital inputs and outputs: optoisolated commands, relay outputs
low perturbation - filtered AC supply
- power circuits in general
- inverter non-filtered AC supply
- contactors
high perturbation
- inverter-motor wires
Measures to take when wiring the cabinet or the system:
•
Sensitive signals and perturbator signals must never exist within a cable.
•
Avoid that cables carrying sensitive signals and perturbator signals run parallel at short distance:
whenever possible, paths of cables carrying sensitive signals and perturbator signals should be reduced
to a minimum.
• The distance between segregated cables should be proportional to the cable length. Whenever possible,
cable crossing should be perpendicular.
Wires connecting the motor or load mainly generate disturbance. Disturbance is important in inverter power
drive systems or the devices installed on the machine, and could interfere with local communication circuits
located near the inverter (radiotelephones, mobile phones).
Follow the instructions below to solve these problems:
•
Provide for a motor cable path as short as possible.
• Screen the power cables to the motor; ground screening both to the inverter and to the motor. Excellent
results are obtained using cables in which the protection connection (yellow-green cable) is external to
the screening (this type of cables are available on the market with a cross-section up to 35mm
2
per
phase). If no screened cable having a suitable cross-section is available, segregate power cables in
grounded, metal raceways.
•
Screen signal cables and ground screening on the inverter side.
• Segregate power cable from signal cables.
•
Leave a clearance of at least 0.5m between signal cables and motor cables.
•
Series-connect a common mode inductance (toroid) (approx. 100 μ H) to the inverter-motor connection.