I'm really loving Node-RED. Kudos to the developers for creating a platform that is so easy to use, well subscribed and well supported.
I'm looking to expand my projects a little with some new end-points, for lack of a better term.
They should be small, take a small power supply and have a few discrete inputs, say 4 and a few discrete outputs, say another 4. Ideally would like to be able to deploy them in multiple rooms over multiple floors in a building.
The arduino nano or pi zero comes to mind but is there something even better suited to this application?
Besides ethernet what comms would you recommend between the end-points and the Node-RED server?
Thanks for those recommendations. Will look into them.
The application is for the control of lighting in each dorm room from a central location. Hence 4 outputs. The inputs would be as a feedback loop to ensure that the contactor that we have switched has indeed responded to have a closed loop system. May use some of the other inputs to check on status of doors and windows if they are open or closed.
Would ethernet be overkill for such an application? Should I be using Modbus or some other means of comms between the server and the clients?
As @Colin suggested the Wemos D1 Mini could be a good candidate for what you want to do.
You mentioned a 'contactor' so I assume you may be switching mains voltage and the current could be significant. In this case you would need some sort of relay (mechanical or solid state) to handle this task.
Please note: As soon as you move into controlling the "mains" you need to pay attention to all aspects of safety (user safety, equipment safety, etc).
For an out of box endpoint shellys are great, no programing required.
multiple protocols and the switches are detachable from the relays, 2 shelly 2 pm's would give 4 outputs and 4 inputs plus power monitoring, they are also work with multiple voltages ac and dc,
They are simple retro to fit . There are shellyi3,i4 and uni to
You haven't said what country you are in, nor shared the building and occupancy types, density, etc.
I suspect that, in most countries, the use of "home made" IoT devices to control large scale mains lighting would be very much frowned upon. That's why most have lots of regulations and require testing and certification.
It is easy enough to build these things as a one-off. To do so safely on a larger scale in areas occupied by ordinary people (or worse - students! ) is something different altogether.
So something like the Shelly's might well turn out a lot cheaper than doing it yourself. Though depending on your locality, a lot more testing and certification might be required even then.
) is something different altogether.