PLCs & Ladder Logic

• Are there any home automation controllers that use ladder logic?

• Related, has anyone here used an industrial PLC in home automation?

I used to do some industrial automation years ago (I'm not up to speed on the latest and greatest) and I'm also building a new home. In brainstorming how to prepare the house for automation, I was thinking about how we used to design our industrial automation systems.
 
I don't think an industrial PLC lends itself to home automation, but I'm curious if its been done and how it was done.

Welcome to CT
 
A lot of us here used the Ocelot from Applied Digital which incorporates a 'ladder logic' like structure.  It's pretty dated now though.
 
I believe there were some here that tried incorporating an industrial PLC (though older one) and have some posts related to the modbus interface.  The main problem with an industrial PLC is it doesn't interface well with conventional home automation hardware.

You might consider checking out the driver for the Koyo CLICK PLC on the CQC forum.  I haven't followed it recently (and it looked beyond my capabilities), but it may give you some ideas.

I use the Click with CQC (and started the driver for it).  I have just purchased my second Click and I am in the process of installing it now.  There is a thrid one planned for use with a VSD for an irrigation system.  At the price they can't be beat
 
Highly recommend it for home automation as long as you can integrate it with your HA system.  In my case CQC is the glue to tie the PLC to the HVAC, Lights and everything else.
 
I went down this path because like you I do industrial automation (mainly DCS') and have some 4-20ma loops installed.  Using a hack on the M1 automation panel I was able to get them (4-20mA signals) into the system, but the PLC supports 4-20 natively and is better suited to control over the M1 - I will leave the M1 for alarm duties only.
 
As an example of what they are doing.
 
The first one is connected to my power meters and counting the kwh pulses and every 15 minutes there is an interval pulse.  I totalize these and on CQC calculate the power cost for the last 15 minutes.  Because I have solar being sold back to the grid I can tell at the end of the day if I have made any money or not.  I can also see when I need to change habits to effect power usage.  This PLC also monitors the electric fence alarm, turns a valve on for supplying water to the horses.
 
I would also consider using one as a weather station, connect the appropriate sensors to it and let it calculate the values and then pass that back to CQC.
 
The new one will have water tank level, water pressure, hot water tank temp, fire sprinkler valve and all other general monitoring and control not associated with the alarm.
 
Just ask away if you have any more questions
 
Mick
 
Others may not agree - this is a personal preference.

I'm glad I registered and asked the question! Thank you for the responses. I'm sure I'll have more questions, but first I need to go study the Click / CQC.

I work in the Industrial Automation industry and the whole of the industry as come together around OPC (Ole for Process Control) as a protocol to talk with devices. If HA could use OPC then a lot of the benefits could cross the fence. Plus all my consignment software would work  

Mayhem702 said:

I work in the Industrial Automation industry and the whole of the industry as come together around OPC (Ole for Process Control) as a protocol to talk with devices. If HA could use OPC then a lot of the benefits could cross the fence. Plus all my consignment software would work

Click to expand...

I agree.  There are a lot of us here that have industrial automation experience.  This will never happen though as developers will put time into drivers/interfaces for the main stream buyer.  This is unfortunate though as it would be interesting...