Emc Directive Requirements; Installing The Got On The Control Panel - Mitsubishi Electric GOT2000 Series User Manual

5.2

EMC Directive Requirements

The EMC Directive requires the following.
• Strong electromagnetic waves are not emitted to the outside.: Emission (Electromagnetic interference)
• The product is not affected by the electromagnetic waves from the outside.: Immunity (Electromagnetic sensitivity)
To comply with the EMC Directive, this section explains the precautions for configuring equipment integrating the GOT.
The data described herein are produced with our best, based on the regulation requirements and standards obtained by
Mitsubishi. However, the data do not guarantee that the whole equipment produced according to the data comply with the
above directive.
The manufacturer of the equipment must determine the method to comply with the EMC Directive and conformance to the
directive.
5.2.1

Installing the GOT on the control panel

The GOT is an open type device (designed to be integrated in equipment).
Make sure to install the GOT in a control panel.
This restriction ensures safety and also has a large effect of suppressing noise generated from the GOT by using the control
panel.
■1. Control panel
• The control panel must be conductive.
• When fixing a top or bottom plate of the control panel with bolts, do not coat the plate and bolt surfaces so that they
contact each other.
Connect the door and the box using a thick grounding cable to ensure the low impedance under high frequency.
• To ensure electric conductivity in the large area as much as possible between an inner plate and the control panel,
do not coat the fixing bolt area of the inner plate and the control panel.
• Ground the control panel using a thick grounding cable to ensure the low impedance under high frequency.
• The diameter of cable holes on the control panel must be 10 cm or less.
If the diameter of the hole is 10 cm or more, radio waves may leak.
To reduce the chance of radio waves leaking out, ensure that the space between the control panel and its door is as
small as possible.
Pasting the following EMI gasket directly on the painted surface seals the space, reducing the leak of electric waves.
KITAGAWA INDUSTRIES CO., LTD.
Our test has been carried out on a panel having the damping characteristics of 37 dB max. and 30 dB mean (measured
by 3m method with 30 to 300 MHz).
■2. Connection of power and ground cables
Ground the GOT and connect power supply cables as shown below.
(1) Wiring the ground cable
Provide a ground point near the GOT. Short-circuit the line ground terminal (LG terminal) and the frame ground
terminal (FG terminal) of the GOT, and ground them with the thickest and shortest cable as possible.
(2) Ground cable length
The ground cable length must be 30 cm or shorter.
The LG and FG terminals pass the noise generated in the PLC system to the ground.
Therefore, ensure an impedance as low as possible.
Since the ground cables relieve the noise, the cables themselves carry a large noise.
Thus, short wiring prevents the cable from acting as an antenna.
(A long conductor is an antenna radiating noise more efficiently.)
(3) Treatment of the power cable and the ground cable
Twist the ground cable led from the ground point with the power cable.
Twisting with the ground cable relieves more noise from the power cable to the ground.
When a noise filter is installed to the power cable, twisting the power cable and the ground cable may not be
required.
5 - 4
5.2 EMC Directive Requirements
Manufacturer
RFSG series (Recommended Product)
Series name
0587-34-3651
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