Avid Technology MV3000 DELTA, Техническое руководство

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T1689 Technical Manual Rev 07 Drive (CDM) Design
MV3000 Air Cooled DELTA Mechanical Design principles
Page 83
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Provide a return path for noisy electrical components.
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EMC filters (if fitted) shunt the noise current from the power connection to the local ground. A
low inductance path to the noise source e.g. DELTA transistor module must be provided. So
should be mounted to a metal panel, which is bonded to the metal framework of the DELTA
power modules.
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Bond control components together.
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For best EMC practice the MV3000e controller, I/O panel and MVM unit (if fitted) must be fitted
to the same unpainted, conductive panel.
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A low inductance, direct electrical bond is required and so an unpainted panel (e.g. plated or
galvanised,) must be used.
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See Section 3.6.8: Position Of Control Components for the recommended layout.
3.5.3.1 DELTA Module Earthing/Grounding Requirements
The steel mounting frame into which DELTA Rectifier or Transistor modules are mounted can be used as the
earthing method provided that:
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The earth continuity is checked between the module earth terminal and the main enclosure earth point.
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The earth continuity must be equal to or less than 0.02 Ω (as stated by IEC 61800-5-1 clause
4.3.5.3), with at least 10 A supplied from a source of not more than 24 V, measured between the
M10 earth terminal and the enclosure earth stud.
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If this value is not achieved then the module must be separately earthed via the M10 earth
terminal at the lower front face of the modules. The M10 earth terminal is identified on the
module by the symbol shown in Figure 3–2.
Figure 3–2. – Protective Earth (ground) Symbol to IEC 60417 (Symbol 5019)
3.5.4 Routing & Segregation Of Cables
3.5.4.1 Segregation Of High Current Or Electrically Noisy Cables To Other Circuits
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Screen the control ribbon cables;
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Bond the screen at both ends;
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See Section 2.15.1 – Screened Ribbon Cables for ribbon cables;
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The ribbon cable bonding clamp at the DELTA transistor module end is provided with the
transistor module;
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The ribbon clamp for the controller end must be separately ordered. See Section 2:
Specification.
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All Analogue I/O and communications cables must use screened cable. The screen must be connected
to earthed metalwork using an uninsulated, metal ‘p-clip’;
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Keep apart sensitive control wiring and power cables;
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Maximise the distance between control and power cables;
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Do not run the control wiring in parallel with power cables;
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a.c. power cables between DELTA transistor modules and filters are especially noisy.