Controlling Solid State Relays (110vac Load)

[klundy]

I have the need to control 50 +/- 110vac Lighting Loads and would like to provide dimming capability.

I believe I can use the Digital Outputs of a T100MD or EXP4040 to turn On & Off Solid State Relays if I use 3-32v Input models.

But can I use the Digital Outputs to provide a PWM type of output using Special Bits / Clock Bits <and/or> some type of a clocked output to provide the dimming function?

If not, is there an expansion module or another solution that would provide a larger quantity of PWM outputs?  

Thanks...

[support]

PWM outputs are only suitable for controlling DC load. AC load are controlled by Triac OR SCR and not easily interface to a PLC.

Since you have so many AC 110V lights, you may want to look for a lighting control system that has RS232 interface (usually designed for a PC to control it). Then you can program the M-series PLC to control the lighting using communication command.

[Joel Moore]

There are analog controlled SCRs out there (e.g. http://www.power-io.com/products.htm).  However you only have 2 analog out per T100MD so if you wanted to control all 50 lights independently you'd need a lot of PLCs.  You could get external analog I/O modules, though, like those from ICP (http://www.icpdas-usa.com/i_7024.html) but you'd need a lot of those as well.

The suggestion above seems like your best bet.

[brettski]

Using a standard output port will only give you a ON/OFF!  What you could use is a Proportional SSR which uses an analogue input for 0-100% of power out.  I use these often and work great!

Hope that helps!

Cheers,

Brett

[cdenk]

Might look at smarthome.com. They have x-10, and others powerline modem stuff that's fairly inexpensive and controllable with RS-232 and maybe other protocols.