Wireless requirement

Hi.

I am pretty sure someone in here has set-up an industrial wireless system. I am very new to this so I am not sure about what type of wireless best suit my application, please help me.

Our client have an existing system they bought from Japan, the brand is Herutu (please see Existing.pdf on attachment). However, as you can observe with the existing system, it can only accomodate 1 set of button per area. They wanted a customized system that will accommodate up to 15 buttons per area (please see OPTION PLANS.pdf files). I am not quite sure what wireless system I will use, what are the important considerations in putting up this sytem & how much will this probably cost.

In my own assessment, the option 1 will definitely cost far less than the option 2. However, I am not sure whether they prefer each box to have its own wireless device or not.

Please do recommend what wireless system suits my application (hopefully most cost-efficient), what do I need to consider (like distance or number of transmitter-receiver that is allowable) & which available systems are cost-efficient.

I was just quite confuse as there are many types of wireless systems available like bluetooth, wi-lan, hart, etc.

Please help. Thank you.

I've worked with three wireless systems.

Wifi (802.11) can cover typically a diameter of 100ft from one access point, maybe up to 200 depending on conditions. Many access points can be used together, but that can increase complexity. I've only worked with units that pass ethernet signals, but I assume RTU type models exist that have IO built in.

WIMAX is an option that has a much larger coverage, on the order of miles from the transmitter. However, this typically requires a license from the the local government telecommunications board (the FCC in the US), which may not be cheap or simple. I've never seen units like these with IO on board, you would probably need a small remote PLC at each station, talking ethernet back to the main unit.

Cell modems are an option when you need a larger area of coverage. You buy SIM cards from your local cell phone provider, and use a data plan to transmit. The downside is that you need a seperate data plan for each radio, which gets expensive. There are probably RTU type devices (on board IO) with cell modems built in.

Another important question is if you only care about the current status, or if you need a timestamped history. If you need to know WHEN the status changed, you might want to look at a protocol with buffering, like DNP3.

Please give a bit more information. Such as: maximum distances needed, I/O types (discrete button/contact type or need of analog), what is the system expected to do (monitor or some control), is a PLC involved and how is it involved.
I have done several wireless I/O systems mostly monitoring discrete and analog signals. A couple of systems were RS485 or Ethernet. Some involved multiple interactions between radios others just sending data to a single point for recording.
Most have been using ELPRO radios (Australia) and have been very reliable. The units used in the US can go 10-20 miles depending on terrain. The power allowed is country dependent. Some of the newer systems can do a mesh communication strategy.

John Soltesz said:

Please give a bit more information. Such as: maximum distances needed, I/O types (discrete button/contact type or need of analog), what is the system expected to do (monitor or some control), is a PLC involved and how is it involved.

Click to expand...

--> 1.) Max. distance is 100 m only, this is inside a production area. 2.) Expecting to send/ receive only discreet signal (1/0) and purpose is only for monitoring.
3.) PLC is involved because it will process the signal received from the buttons, whichever button is pressed the monitoring board will indicate it.

theripley said:

--> 1.) Max. distance is 100 m only, this is inside a production area. 2.) Expecting to send/ receive only discreet signal (1/0) and purpose is only for monitoring.
3.) PLC is involved because it will process the signal received from the buttons, whichever button is pressed the monitoring board will indicate it.

Click to expand...

There are units that will map the remote inputs to MODBUS and communicate to the PLC on an RS485 line. This would save on I/O modules and wiring. I have not needed to do this. Otherwise you can expand the receiving unit at the PLC and connect individual outputs to the PLC inputs. Lots of options.

This system will give you what I think you’re looking for. It has eight discrete inputs on each remote (as well as eight discrete outputs and analog channels) and when using the Protocol Master it will support up to 16 remotes (128 discrete inputs total). The Protocol Master will interface with DF1, EtherNet/IP, Modbus RTU or Modbus/TCP and the PLC reads from it or writes to it as if it were another Allen Bradley PLC or Modbus slave (depending on the PLC used). So in other words, the PLC interfaces with the Protocol Master using one of the above mentioned protocols and reads the status of all of the remotes. They have both 900MHz and 2.4GHz versions all of which are license free. They also have long range version (the CIX versions) or medium range versions (the PLR version). The CIX will go 25+ miles while the PLR will go up to 5 miles so indoor applications are effortless and very reliable.
http://www.data-linc.com/cixfamily/cix6400.htm