Mitsubishi Electric NZ2EX2B-60AD4 User Manual page 238

(2) Installation in a control panel
The module is open type devices and must be installed inside a control panel.
This ensures safety as well as effective shielding of programmable controller-generated electromagnetic noise.
(a) Control panel
• Use a conductive control panel.
• When securing the top or bottom plate using bolts, cover the grounding part on the control panel so that
the part will not be painted.
• To ensure electrical contact between the inner plate and control panel, take measures such as covering
the bolts so that conductivity can be ensured in the largest possible area.
• Ground the control panel with a thick ground cable so that low impedance can be ensured even at high
frequencies.
• Holes in the control panel must be 10cm diameter or less. If the holes are larger than 10cm, radio wave
may be emitted. In addition, because radio waves leak through a clearance between the control panel and
its door, reduce the clearance as much as possible. The leakage of radio waves can be suppressed by the
direct application of an EMI gasket on the paint surface.
• Our tests have been carried out on a control panel having the attenuation characteristics of 37dB (max.)
and 30dB (mean) (measured by 3m method, 30 to 300MHz).
(b) Wiring of power cables and ground cables
• Near the power supply part, provide a ground point to the control panel. Ground the FG terminal with the
thickest and shortest possible ground cable (30cm or shorter).
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