ethernode® basics


If your Ethernet has to reach outside your office environment - e.g. to an outbuilding with the emergency backup generator or into the cellar with the suction pump - to read switches and sensors or to operate valves or relays a standard PC is inappropriate. This is where ethernode® comes in: An IP65 surface box with LSA terminals for Ethernet installation cable, spring cage clamps for i/o and remote supply through the Ethernet cable (PoE). Despite its small size ethernode® contains a real time kernel, a web server with access to local tasks and i/o, e-mail capability, and TCP/IP sockets. A graphic display option serves the need for local intervention.

An overview of ethernode ® products can be found here.

  • Electrician-friendly IP65 surface box 9x13cm
  • Extended ambient temperature range: -40..+50°C
  • 10/100 MBit Ethernet with remote supply option through commodity PoE switches
  • PoE leaves 24V/>150mA for your user relays, actors, switches,...
  • LSA terminal block for patch or installation cable
  • Cage clamp terminals for all I/Os
  • ARM microcontroller with real time kernel (mCAT)
  • 2MByte Flash-EPROM for your C programs and web pages
  • 256K RAM (1M option) with buffer cap for > 8 days
  • Real time clock; buzzer for acoustic announcements
  • Status-LEDs in the top-cover: User, ETH, mCAT
  • Serial interface Ser0: RS232
  • Serial interface Ser1: Choice of
    • RS232 with RTS/CTS or
    • RS485 full or half duplex
  • Choice of other I/Os:like
    • 24V-inputs, opto-isolated
    • 24V outputs with relays or short-circuit proof ICs
    • Analog inputs Pt100 RTD, thermocouple, 4..20mA
    • 230V mains I/O
  • Web server with mSP tags for live I/O
  • I/O-access directly from Windows through nodeAccess™
  • COM emulation for Windows®-computers
  • SerDrv driver api from a local mCAT-task
  • TCP/IP-communication over socket interfaces.
  • Details

Today, with Ethernet wiring being commonplace in an office and many homes, it suggests itself to use this infrastructure to integrate access to gates, pumps, lights, temperature sensors etc. Getting there, however, might require the descent to inhospitable corners of a building like cellars or sheds. Exactly the area ethernode is meant to be: An electritian can bolt the surface box directly to the wall, cables are neatly kept in a row of cable glands and are easily connected to the spring loaded cage clamp terminals for each wire (yes, we try to provide enough terminals for the returns and shields, too). For Ethernet, you probably won't have a switch nearby, so the box offers an LSA terminal for standard CAT5,6,7 wiring cable - although patch cable fits, too. And as usually there is no 24V-supply in the hindmost corner, ethernode can be supplied over the Ethernet-cable from its PoE-switch. Our PoE DC/DC converter not only feeds the CPU but presents some 24V for local initiators or small valves. The only 9x13cm sized IP65-box made of fiber-glass-reinforced polycarbonate bears rain and performs peaceful coexistence with spiders.

Communication in all directions!

Being rugged doesn't mean ethernode lacks IT-capabilities: Not only one but three built-in web servers allow different services like configuration or maintenance on different ports. Server side processing on ethernode allows live data to show up on web pages, our own "mSP"-tags like are replaced by input data or variables on presentation. Use your preferred HTML-Editor to build pages that display states or even modify recipes for batch processes.
But a browser is not always the agent that will interact with ethernode®, in automated processes, your application program on a PC or mainframe would need immediate data access to ethernode. For such scenarios our nodeAccess™-DLL provides communication with ethernode's i/o and registered objects. After having installed the nodeAccess™-DLL on your Windows® PC, you can work on your ethernode's ports just as if they were local. To use the serial ports on ethernode, there is a virtual COM-interface that emulates the ethernode ports as local ports to your PC.

Some situations would require local programming on ethernode®: Protocol conversion between Ethernet and a custom RS485 subnet for instance or having some stand-alone control application. Here the mCat real time kernel enables complex programming on ethernode - with parallel tasks and message-communication between tasks, interrupts and the network. Ethernet messages are received by ordinary tasks through TCP/IP socket interfaces, hence organically integrated into the standard message exchange mechanisms. The socket interface provides for the most flexible ways of client-server communication and most compilers or data bases on the PC offer a socket communication option.

Mechanical structure

ethernode® consists of two boards: The processor with a clipped-on power supply (24V or PoE) in the protected lid and the in-/output-board in the bottom. Wiring is constrained to the bottom with its pcb protected by an intermediate isolation board from loose cable ends or screwdrivers slipping off. Terminals are properly marked and the spring loaded cage clamps allow for fast wiring. Various in-/output-boards are available depending on whether you prefer relay (any low voltage, AC/DC) or 24V IC outputs (short circuit proof), need analog inputs or would like to switch mains voltage. The minimum i/o-board is the ETH-A7-2SER, it has the two serial lines only. Please select the desired i/o-configuration from the list in the right column.

If local user interfaces would add convenience to your setup, it is a cheap choice to go for the ethernode LCD versions that have a 128x64 pixel graphic display and some function keys integrated into the boxes lid.

A maximum of three M12 and two M16 cable glands are available on the front side of the bottom, while on the left side an M20 thread is available for extensions like the 4I4RHV or particularly thick cables. In case the extension is not used, we can offer a special M20 cable gland with holes for multiple cables (2x6, 3x6, 5x4mm). If you need to have separate cables for each of for instance 3A4IO's inputs, such a multi-cable gland is unavoidable. There, the M16s can be replaced by a special version for three 5mm cables, too. On units with less i/o ports, the M20 is closed by a dummy plug.