Multiple AC inputs relay (light PLC)

Thread Starter

my_first_name

Joined Aug 18, 2019
2
Hi,
I have a circuit like in attached diagram (multiple switches associated with light bulbs in different rooms). I'll like to add a new device (the green one with question marks) that has the following "specs":
- 230V AC powered
- 10 to 16 230V AC inputs (the same AC phase, but will be nice to have different phases too)
- 1 to 3 relays (classic NO/NC) outputs
- it should trigger based on how many input lines have active power (the number of active inputs to trigger should be adjustable from outside (jumpers, switches, etc)
As a practical implementation example will be to trigger an actuator which closes a window if there are more than 3 lights turned on and to open the window if there are 3 or less light switched on.
Most probable I need a PLC / PLR, but I hope there are other devices to do this in an easier way. So the question is: Are there such devices? If yes, what is their name?
If I have to go with PLC, can you please recommend some to me? (So far I've seen that there are very few relays, PLCs or actuators running native with 230V AC inputs).
Notes:
- I'll like to keep the light part in existing form (so no Dali/KNX/similar switches)
- It will be nice to be able to associate different "weights" to different inputs.
DiagramAuto.jpg
 

MaxHeadRoom

Joined Jul 18, 2013
19,197
I don't recall coming across any PLC's with 230vac inputs, the majority are 24vdc now, some of the Allen-Bradly ($$$) may have had it, IIRC, but you may be hard pressed to find one now.
The lamps you show are not needed, a PLC has indicators inputs.
Any lamps would go on the output.
You could make one up using a small micro and interface with Opto22 boards and modules that have AC voltage in and any type of out put you need.
Can you now transform the switch inputs to 24v for a off the shelf PLC or Smart Relay?
Max..
 

Thread Starter

my_first_name

Joined Aug 18, 2019
2
The lamps are actually needed to light my rooms. I just want to make an addition to existing circuit but keep my light untouched.
However, I like the idea with Opto couplers. I have to deal with more wires, but this is something I can do if there are no 230V PLCs.
Switch input should be kept at 230V for my lights. Another idea you gave me is to use 10-16 small transformers to switch from 230V AC to 24V DC instead of 10-16 relays and a common DC power source.
I don't like "soldering" part so I like to keep hardware as compact and "single piece out of the box" as possible.
Which PLC would you recommend me if I'll make a conversion somewhere and switch from 230V AC to 24V DC?
 

MaxHeadRoom

Joined Jul 18, 2013
19,197
For those getting into it, the Automation Direct offer a good choice with IIRC free software, I use Mitsubishi primarily, but I have the S/W and PC-PLC cable.
I also posted a link recently where Automation Direct has a PLC tutorial for theirs.
Max.
 
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