Looked to hardware a few I/O's at a great distant

Hi, it's been a few years since I have posted in this group.

I'm looking for a product of some sort that can connect a handful of I/O's a few hundred feet away from the PLC. Say for example, a level indicator and motor valve control on a water storage clear on the other side of the property. Power is available at the I/O's. I was thinking something really generic that can be transmitted via CAT data cable that runs a simple protocol. Like a module at the PLC converts the electrical signal at the PLC to a data signal that communicate through the CAT cable deirectly to like module at the I/O's. Without the need of network switches, seperate computer, network interfacing etc. something that can handle 4 to 6 I/O. Nothing fancy, not requiring subscription service, not requiring expensive software outside of configuring the unit when setting it up, and can be routed with other CAT cables on exiting cable trays, conduit, etc. sorta like a simple, hard wired SCADA system that's basically plug and play.

It don't have to be PLC dependent. Say for example (theoretically speaking), I get bored and want to use this system to have the light switch in my dining room be interconnected to the room light via the two modules, intconnected via CAT cable.

The simplest solution would be to have a Modbus RTU device connected to the PLC using an RS485 link. The Automation Direct Productivity range do this well. You would be using twisted pair rather than CAT cable though.

Ethernet is good for 300 ft so you would be ok with Ethernet IO
but you may want to consider radio extender
I have used ethernet IO connected with a radio communication with no problems
the PLC dosen't even know the radio is there
you can get radio extenders that will reach over miles just keep in mind it should be line of sight

Use a Ubiquity ethernet radio.

Any CIP capable I/O module should work.

HMS Anybus Wireless Bolt .... 100 meters ... ANY protocol.

https://www.anybus.com/products/wireless-solutions/wireless-bolt

Hi, thanx for the input. I PM'd you

EtherCAT remote I/O station can be extended 100M (328 Ft). You would use one cable (standard CAT5e cable will work). No switches or other hardware required. If you need to reach beyond 100M, then you may need to consider wireless.

I bought a OneFex remoteIO module that uses ModbusRTU over Ethernet (or serial DH485) as a test. It comes in a variety of digital and analog/digital configurations. I bought the 4DI, 4AI, 4DO for $75.



I have it setup - but for my CLX test rack I need to upgrade the ENT card to one that does packets, and as it's a test rack haven't budgeted it yet.


EDIT: If they are ever in good supply the Automation Direct Click can be used as CLX remote IO even if it doesn't have a program in it.

WHat about - https://www.phoenixcontact.com/en-gb/radioline-wireless-system

NetNathan said:

HMS Anybus Wireless Bolt .... 100 meters ... ANY protocol.

https://www.anybus.com/products/wireless-solutions/wireless-bolt

Click to expand...

Not ANY - it doesn't support EtherCAT.

I am questioning the insanity of some of these recommendations.

Have they been used by you in the field? How reliable are they?

For example, Onefex's price point looks good, but it does not seem to be tested out yet by the one who recommended, so you don't even know how reliable it is. The company has an address somewhere in China, and the only communication available is by email or Whatapps. This could be a red flag here. I don't even use WhatsApp. And their chips are probably from Huawei that I probably get to be concerned about.

In the industrial world, Modbus RTU protocol on RS-485 wiring is about as close to a simple, universally compatible communications standard as exists.

But with that widespread use and adoption comes a great deal of variety: no two vendors seem to label the Data +/- terminals the same or choose 0/1 offset addressing the same. The meanings of Modbus flat data register arrays are up to the vendor, every time.

RS-485, if carefully installed and isolated, can go long distances over a variety of wire. For example, A-B's 19.2 kbit/second "DH485" networking, with good isolation and proper Belden twisted-pair wire, is good for 4,000 feet or so.

But with that wide flexibility comes nothing like "plug and play". Every device can be a little different, so you need a working knowledge of the protocol and sometimes a serial tap.

If someone told me "I have a PLC with a Modbus RTU Master port, give me a handful of 24V discrete I/O that are not time critical", I would buy an Advantech ADAM module and be confident I could get it set up with the PLC.

If the order was for thousands of them, or needed fast control, or a complex set of mixed signals, maybe I would choose a different platform.

My experience with RS485 over a distance more than 100 feet has been to use serial port isolators at all the ports BEFORE lightning hits anywhere near that cable rather than AFTER it pops both (or all of) the serial ports that are linked.

Yes, been there and done that with a 750' RS485 link between a P2000 and 2 Yaskawa drives and it was an expensive lesson.