Created Date: October 28,2019

Created by: rdean72

I am doing some work for a local community. The water towers have an automatic level detection system. This system is based on sensors providing a 4-20 mA signal to a chart recorder. When the level is too low the chart recorder turns on the water pump at the water plant. When the level gets to the correcty level, the pumps are turned off. This 4-20 mA signal is sent over a dedicated analog line provided by AT&T. It is extremely expensive. I would like to convert the 4-20 mA signal to digital, send it across ethernet to our water plant and convert back to 4-20 mA. We would be getting rid of the analog line and using AT&T Internet with static IP. Any ideas or information would be a big help. I have purchased a laurel electronics Model LTE20P Analog input, ethernet & Isolated 4-20 mA outputs device and routers to start with.

Created Date: October 28,2019

Created by: Garry

https://www.automationdirect.com/adc/shopping/catalog/programmable_controllers/click_series_plcs_(stackable_micro_brick)/plc_units/c0-12dre-1-d

Two Click PLCs with Ethernet and Analog Current on board would work.

Click PLCs would communicate with each other using Ethernet (Modbus TCP).

https://accautomation.ca/modbus-rtu-click-plc-master-to-brx-plc-slave-communication/

The above post will use a Click as the master communicating to a BRX Do-More slave, but this program would be similar to the communicating over ethernet using two Clicks.

I hope this helps you out.

Regards,

Garry

Created Date: October 28,2019

Created by: OkiePC

Depending on the distance, you could use radio modems and eliminate the monthly internet expense altogether. What modems to use depends on distance mostly, but also budget. We have used $75 Ubiquiti NanoStation M2 with the Click PLC for distances up to about a mile with good line of sight, and could probably go farther.

I normally use an add on analog module at the tower PLC since that part will eventually get zapped by lightning and is easier to replace (along with the pressure sensor) and doesn't require any programming. I am a big fan of the ProSense 4-20mA transmitters with the 4 pin DC micro connector. At a little over $100 they are truly plug and play for my non-technical customers who run small town and rural water systems.

At the other end PLC, I will usually use a HMI that allows operators to view tank level, adjust start, stop and alarm settings, and offer email/sms alerts (since most water plants or main offices already have internet). We also like the Stridelink VPN router for secure remote access. The operator can view tank level and start and stop pumps from anywhere in the civilized world with his smart phone. And if he gets in over his head or there is a PLC problem, I can remote access the PLC and HMI and make a diagnosis or even change the logic.

Created Date: October 28,2019

Created by: MikeN

If this is a city thing with the water towers then pushing permits through for Ubiquiti equipment should be a breeze. They have equipment for between 0-10 miles, as well as BIG radios for long haul stuff that goes 10-30 miles. I have personally used some of their lower end stuff to shoot a LAN about 6 miles across a city without big towers or needing permits.

You should look at the monthly cost for data lines from ATT for each water tower, then compare that to the cost of using Ubiquiti equipment If the ATT stuff would add up to the same cost or more in a year compared to the initial expenditure for Ubiquiti hardware then you should probably just go with dedicated hardware. I have used the stuff for around 5 years now without a single issue.

Created Date: October 29,2019

Created by: rdean72

https://www.automationdirect.com/adc/shopping/catalog/programmable_controllers/click_series_plcs_(stackable_micro_brick)/plc_units/c0-12dre-1-d

Two Click PLCs with Ethernet and Analog Current on board would work.

Click PLCs would communicate with each other using Ethernet (Modbus TCP).

https://accautomation.ca/modbus-rtu-click-plc-master-to-brx-plc-slave-communication/

The above post will use a Click as the master communicating to a BRX Do-More slave, but this program would be similar to the communicating over ethernet using two Clicks.

I hope this helps you out.

Regards,

Garry

Thank you Gary,

I am going to research this. I am fairly new to the programming part.

Created Date: October 29,2019

Created by: rdean72

Depending on the distance, you could use radio modems and eliminate the monthly internet expense altogether. What modems to use depends on distance mostly, but also budget. We have used $75 Ubiquiti NanoStation M2 with the Click PLC for distances up to about a mile with good line of sight, and could probably go farther.

I normally use an add on analog module at the tower PLC since that part will eventually get zapped by lightning and is easier to replace (along with the pressure sensor) and doesn't require any programming. I am a big fan of the ProSense 4-20mA transmitters with the 4 pin DC micro connector. At a little over $100 they are truly plug and play for my non-technical customers who run small town and rural water systems.

At the other end PLC, I will usually use a HMI that allows operators to view tank level, adjust start, stop and alarm settings, and offer email/sms alerts (since most water plants or main offices already have internet). We also like the Stridelink VPN router for secure remote access. The operator can view tank level and start and stop pumps from anywhere in the civilized world with his smart phone. And if he gets in over his head or there is a PLC problem, I can remote access the PLC and HMI and make a diagnosis or even change the logic.

Thank you OkiePC,

Are their any videos out there describing these process?

Created Date: October 29,2019

Created by: rdean72

If this is a city thing with the water towers then pushing permits through for Ubiquiti equipment should be a breeze. They have equipment for between 0-10 miles, as well as BIG radios for long haul stuff that goes 10-30 miles. I have personally used some of their lower end stuff to shoot a LAN about 6 miles across a city without big towers or needing permits.

You should look at the monthly cost for data lines from ATT for each water tower, then compare that to the cost of using Ubiquiti equipment If the ATT stuff would add up to the same cost or more in a year compared to the initial expenditure for Ubiquiti hardware then you should probably just go with dedicated hardware. I have used the stuff for around 5 years now without a single issue.

Thank you MikeN,

I am working on another project in the country for a friend. They want to connect to a friends broadband connection about 5 miles away. I bet this would work for his problem. I will also check out the prices and put it to the city council to verify the permits and expenditures.

Created Date: October 29,2019

Created by: OkiePC

Thank you OkiePC,

Are their any videos out there describing these process?

There are probably some videos on the different pieces involved, but not all of them and not one video for the whole project. Click PLC hardware and software videos exist for that part of it:

Click analog modules kickstart video:

https://www.youtube.com/watch?v=acl_Pak_JP4

Created Date: October 29,2019

Created by: MikeN

Thank you MikeN,

I am working on another project in the country for a friend. They want to connect to a friends broadband connection about 5 miles away. I bet this would work for his problem. I will also check out the prices and put it to the city council to verify the permits and expenditures.

Prices are pretty cheap. Main cost is usually permits and getting the installation done, however it sounds like you already have power to each tower so the hard part of installation is already done. Depending on what models you go with you may not even need permits. Around me, CalTrans uses Ubiquiti gear when doing freeways and they string up a bunch of point to point dishes along the freeway and dont need permits at all. These are the products I would be looking at:

https://www.ui.com/airmax/powerbeam-ac-iso/

https://www.ui.com/airmax/litebeam-ac-gen2/

https://www.ui.com/airfiber/airfiberx/

https://www.ui.com/airfiber/airfiberx-antenna/

Configuration on all of them would be identical or nearly so to the video Garry posted.