Noise Countermeasures - Epson RC420 Manual

Setup & Operation 3.4 Noise Countermeasures (Installation)

3.4 Noise Countermeasures

To minimize electrical noise conditions, the following items must be observed in the
system's cable wiring:
- The earth wire of the power supply should be grounded. (Ground resistance: 100Ω or
- Do not tap power from a power line that connects to any equipment which may cause
- When you tap power for the Controller and the single-phase AC motor from the same
- Use a twisted pair motor power line.
- Do not run AC power lines and DC power lines in
- For I/O lines, wire as short as possible and use a shielded cable and clamp the shield to
- Use a shielded cable for the EMERGENCY connector and clamp the shield to the
- Make sure that the induction elements used to connect to the Controller's I/O (such as
- To start and change revolutions of the conveyer's (or the like's) AC motor (ex: an
- As they are easily influenced by static electricity or the noise from power source, keep
NOTE
It is sometimes effective in suppressing such noise to wind the keyboard or mouse cables
around a ferrite core several times.
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less)It is important to ground the frame of Controller not only for prevention from
electric shock, but also for reducing the influence of electric noise around the
Controller. Therefore, be sure to connect the earth wire (yellow/green) of the
Controller's power cable to the ground terminal of the factory power supply. For
details about the plug and AC power cable, refer to the Setup & Operation "3.2.2
Power Plug.
noise.
power line, change the phase of one or the other. Ensure that they will not be the
same phase.
the same wiring duct, and separate them by at least
200 mm. For example, separate the AC motor
power line and the Controller power line by at least
200 mm from the sensor or valve I/O lines; and do
not bundle both sets of wiring with the same cable
tie. If more than one duct/cable must cross each
other, they should cross perpendicularly.
preferable example is shown in the right figure.
the attached connector interior.
interior of the connector.
relays and solenoid valves) have surge suppressors. If an induction element without
surge suppressor has be used, make sure to connect a rectifying diode right in front of
the induction element. In selecting a rectifying diode, make sure that it can handle
the voltage and current incurred by the induction load.
induction motor or three-phase induction motor) regularly or abruptly, make sure to
install a spark suppressor between the wires. The spark suppressor is more effective
when placed closer to the motor.
the mouse and keyboard away from peripheral noise sources.
AC Line duct
200 mm or more
DC line duct
The
RC420 Rev.9