Raspberry Pi Forums

Hello,

I need to control 36 devices over digital outputs (or relays) and also, I need to get digital signal from it (pressed button), so I need 36 more inputs. I would like to control it from RPI.
Can you suggest any of your devices for that? It is ok, if I will connect several relay stations (controllers) to RPI. Also, should be good solution to connect it over TCP/IP.
So far I found:
http://www.moxa.com/product/ioLogik_E1212.htm
But it is really expensive..

I prefer to buy it as product..

Any suggestions?

Thank you
Lukas

You need to specify the operating voltage for the inputs and outputs.

You will not find a single device, nicely packaged, based on a Pi for your need.

Such industrial I/O is expensive. Google for Opto-22, they have some modules.

If you specified your exact needs, ie how far the I/O needs to be, do they cluster in smaller amounts (ie 8 in / 8 out per location), distance between locations etc you may be able to get more help.

Other important factors are:

- what certifications (if any) is required for the equipment
- will you assemble, into proper housing
- have you done such electrical work etc

I have over 30 years of experience in industrial control, but you did not give enough information for people to be able to help you.

nso wrote:Hello,

I need to control 36 devices over digital outputs (or relays) and also, I need to get digital signal from it (pressed button), so I need 36 more inputs. I would like to control it from RPI.
Can you suggest any of your devices for that? It is ok, if I will connect several relay stations (controllers) to RPI. Also, should be good solution to connect it over TCP/IP.
So far I found:
http://www.moxa.com/product/ioLogik_E1212.htm
But it is really expensive..

I prefer to buy it as product..

Any suggestions?

Thank you
Lukas

PCF8574T IO Expansion Boards (available on ebay for about £3.50 each)

For additional digital inputs and outputs you could use these I2C-Bus modules. You can put eight on a single I2C bus giving you an additional 64 inputs. The pi has two I2C connections (a second one on P5) so I presume you can add 128 digital IO lines.

Hi Lucas,

Some question need to be answered first.

What is the maximum distance between your sensor?
How many modules you need?
Could you use something else than ethernet?
And of course what kind of voltage input you need?

- If everything could be centralized, a simple I2C expander and some Raspberry Add-on board will do the trick.

- If it is around different buildings, maybe an arduino with ethernet shield will be better.

-if it is on different location in the same building then you could use simple PLC controller , like some cheap ethernet modbus PLC at Automation Direct.

I was on the same road and I made myself a board. It is not ethernet but it could use the same cable.
Please check this post.

http://www.raspberrypi.org/forums/viewt ... 06#p618006

This is about a small board I made with 10 I/Os that could be set to different mode.

The cost is just a little more expensive than aduino UNO but at least I do have a plastic box and terminals with screw.

The github contains the Gerber and you could just send directly to iteadstudio.com. The pcbs will cost around $20 (for 10) with shipping.
https://github.com/danjperron/PIC_MULTI_10_IO
If you are not afraid to build the board, this is the cheapest way.

Daniel