Omron EJ1 - 07-2008, Operation Manual

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Conformance to EC Directives
The EJ1 DeviceNet Communications Unit complies with EC Directives. To
ensure that the machine or device in which the Unit is used complies with EC
Directives, the Unit must be installed as follows:
1,2,3... 1. The Unit must be installed within a control panel.
2. You must use reinforced insulation or double insulation for the DC power
supplies used for the communications power supply, internal power supply,
and I/O power supplies.
3. Units complying with EC Directives also conform to the Common Emission
Standard (EN50081-2). Radiated emission characteristics (10-m regula-
tions) may vary depending on the configuration of the control panel used,
other devices connected to the control panel, wiring, and other conditions.
You must therefore confirm that the overall machine or equipment complies
with EC Directives.
4. The Unit is a Class A product (products for industrial environments). In res-
idential environment areas it may cause radio interference, in which case
the user may be required to take adequate measures to reduce interfer-
ence.
The following example shows one means of reducing noise.
1,2,3... 1. Noise from the communications cable can be reduced by installing a ferrite
core on the communications cable within 10 cm of the DeviceNet Unit.
Ferrite Core (Data Line Filter): 0443-164151 (manufactured by Fair-Rite Prod-
ucts Co., Ltd.)
Impedance specifications
25 MHz: 105
Ω
100 MHz: 190
Ω
30 mm
13 mm
29 mm
33 mm
2. Wire the control panel with as thick and short electric lines as possible and
ground to 100
Ω
min.
3. Keep DeviceNet communications cables as short as possible and ground
to 100
Ω
min.
30 mm
13 mm 29 mm
33 mm