Epson RC90 User Manual

Setup & Operation 3. Installation
3.5 Noise Countermeasures
To minimize electrical noise conditions, the following items must be observed in the
system’s cable wiring:
To minimize electrical noise condition, be sure of followings for wiring.
- The earth wire of the power supply should be grounded. (Ground resistance: 100 Ω or
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 3.3 Power Supply.
- Do not tap power from a power line that connects to any equipment which may cause
noise.
- When you tap power for the Controller and the single-phase AC motor from the same
power line, change the phase of one or the other. Ensure that they will not be the same
phase.
- Use a twisted pair motor power line.
-
Do not run AC power lines and DC power lines in the
same wiring duct, and separate them
as far as
possible
. For example, separate the AC motor
power line and the Controller power line
as far as
possible 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. The preferable
example is shown in the right figure.
AC Line duct
DC line duct
As far as
possible
- Wire as short as possible to the I/O connector and EMERGENCY connector. Use a
shielded cable and clamp the shield to the attached connector interior. Make sure to
keep away from the peripheral noise source as far as possible.
- Make sure that the induction elements used to connect to the Controller’s I/O (such as
relays and solenoid valves) are noise suppression parts. If an induction element without
protection against noise is used, make sure to connect a noise suppression part such as a
diode located at the induction element in parallel with it. In selecting noise suppression
parts, make sure that they can handle the voltage and current incurred by the induction
load.
- To start and change revolutions of the conveyer’s (or the like’s) AC motor (ex: an
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.
- As they are easily influenced by noise, keep cable such as USB, Ethernet, RS-232C, or
fieldbus away from peripheral noise sources.
26 RC90 (EPSON RC+ 7.0) Rev.4

Epson RC90 Specifications

General

Brand	Epson
Model	RC90
Category	Controller
Language	English