On the road again
I write this in the car on the way to Illinois. Meeting with a Motion Control Distributor today.
I’ve brought Drew Baryenbruch, our marketing director, along with me on this trip. Drew is real smart about marketing industrial products but more than that he doesn’t mind driving. And I HATE to drive. It’s just such a waste of time, monotonous and frustrating. But I have to watch Drew pretty closely – he’s already taken one wrong turn.
The Motion guys were seeing today brought me an interesting application. They have some CANopen devices that are, of course, out of Europe. As is typical with European manufacturers they build in one of two protocols; Profibus DP or CANopen.
Profibus DP is a very impressive network. High speed, reliable, easy to use. But expensive. VERY expensive. Because it runs at 12Meg, it needs a low level ASIC and that ASIC isn’t cheap. The connectors are specially designed (no power on the bus) and very costly also. The biggest factor in using Profibus is that it’s easy to connect a Profibus DP device to a Siemens S7 PLC. If the application has an S7 – Profibus is usually the best choice.
CANopen is the other heavily used European sensor bus protocol. Were Profibus is almost exclusively used in Manufacturing applications, CANopen is used more in non-industrial and medical applications. You’ll find tons of CANopen in hospitals and medical devices. There are patient beds that use CANopen to send signals to all the motors around a bed.
CANopen is what our distributor friend here has. I had our super smart engineering staff come up with a board for them that adapts that CANopen connection on their device to Modbus TCP, EtherNet/IP and DeviceNet. That makes the device much more saleable in the US.
This is a pretty common occurrence for us. When we build EtherNet/IP Circuit boards, DeviceNet Circuit boards and Modbus TCP circuit boards we customize the device for the target network. When you interrogate the device you get all the identify information that is specific to their company and the objects that are specific to their application. You can’t get that kind of device representation with an off-the-shelf interface module like Anybus.
Another common request for us is to meet some sort of hard, footprint requirement. For example, Aquasensors needed a very tiny footprint DeviceNet board. And as far as I know the board pictured here is the smallest DeviceNet board ever made.
Picture of aquasensor board with quarter
AS I always say: “RTA is the Burger King” of industrial automation development. You get it your way…guaranteed.
Johnr
February 9th, 2010 at 12:19 am
Hi John,
I think you make some interesting and accurate statements regarding CANopen. In my opinion, the only factor which has really held CANopen back from becoming more popular in North America is that the one and only big PLC player in the US, Allen Bradley, spun Devicenet as way of controlling the I/O market. The two network protocols, CANopen and Devicenet provide almost identical network functions. I deal with CANopen on a daily basis, and have developed and programmed a CANopen stack so I’m very familiar with the protocol, and having helped many customers new to CANopen, in my opinion another major factor limiting the network being used more in North American industrial applications is the lack of good low cost network configuration tools and network adapters.
Best Regards,
Frank
(that is one small Devicenet node for sure…)