Weed Instrument 2C20 Interface Module Guide De Spécification

Weed Instrument Fiber Optics

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Weed Instrument’s EOTec 2000 ControlNet communications
modules are designed to provide networking solutions in
harsh industrial environments. The 2C20
ControlNet electrical interface module can be used
alone for electrical communications on the physical
media layer of a ControlNet trunk line, or with any
EOTec 2000 optical interface module for greater
distances and higher reliability between ControlNet
devices. Problems such as ground loops, EMI/RFI
noise and lightning strikes are eliminated by using
fiber optic cables in lieu of copper coaxial cables.
Create your own “stack” to build a ControlNet repeater,
extend the length of a ControlNet network via copper or
fiber, create a STAR or daisy-chain topology using copper

or fiber, or, combine all three topologies in one network.

Each EOTec 2000 communications module features a

truly scalable DIN-rail mount package that allows for
up to five modules to be snapped together on one
stack powered by one or several power supply 
modules.

Communications takes place through its unique

“backplane port” with no external wiring between
modules. LED indicators are provided for local
determination of communication failures. In addition,
Weed offers optional modules with enhanced 

diagnostics that can be wired to provide failure information
at a remote location.

Easy Plug-In

Connector

A ControlNet communications stack can 
be equipped with up to four standard optical
interface modules (2Exx series) or optical
interface modules with enhanced 
diagnostics (2Dxx series). Optical interface
modules with diagnostic outputs have an
internally powered 4-20 mA output, which
provides indication of the received optical
power level (light intensity) from the fiber.

The EOTec 2000 system can be used to create many differ-
ent network topologies using copper coax cable or glass
fiber cable. Adding additional modules provides users with
a string of communication stations or communication to an
array of stations (STAR) from a centrally located “hub”. In

the simplest case, the modules can be used to convert a
copper line to a fiber optic cable to increase the noise
immunity of the system. Depending on the application
other networks are possible.

The output is calibrated for each model
so that a reading of 4mA means the opti-
cal receiver is at its threshold for recover-
ing the optical signal (optical link failure is
imminent). A reading of 20mA corre-
sponds to the full optical budget being
available at the optical receive port (very

healthy optical link).