I'm in a somewhat urgent need of a temporary solution; so far my experience has been limited to simple hobbyist coding/prototyping with breadboard components but need to address an industrial issue quickly.
Based on sensor input I need to open (de-energize) a 220V single-phase normally-open contactor to a motor. I have the front end (sensor I/O and logic) designed and coded, but don't know where to start with translating the logic output to actuating an industrial contactor. 120VAC is available to power both the microcontroller power adapter and contactor. What sort of components/architecture and signal path do I need to be looking at?
Secondary question--is there a microcontroller out there similar in use/function as an arduino that is built more for industrial applications, i.e. reliable indefinite continuous sensor monitoring? Once I've got a prototyped solution with the arduino I'd like to build a permanent solution of similar design.
Thank you in advance for any advice as I continue to research.
While I probably would not use an Arduino for this, if I had to I would use an interposing relay.
Find a optically isolated relay card that works with the Arduino (like this http://www.amazon.com/Tolako-Module-Arduino-Official-Boards/dp/B00VRUAHLE/ref=sr_1_2?ie=UTF8&qid=1464908814&sr=8-2&keywords=arduino+5v+relay+board
There are numerous micro PLCs that could do this job. I did find a enclosure on Amazon that lets a Uno be mounted on a din rail LINK
Thank you for the ideas, I like the idea of an interposing relay. Unfortunately most of the relays I have found on a quick search that are directly adaptable to a microcontroller, or PLC units, handle up to 10A. It's a 40hp rotary phase converter running off a 250amp single-phase breaker (may be higher, I'm still waiting on more info).
I was recommending a relay like that to act as the run command to the existing motor starter, not run the motor directly, or to drop the run command out.
Do you have the existing motor elementries / wiring diagrams?
It’s a 40hp rotary phase converter running off a 250amp single-phase breaker (may be higher, I’m still waiting on more info).
As I believe it is emphasized in the previous reply, you aren’t needing to control the 250 amp a/c with a relay, rather only the current to the coil of the motor contactor. Perhaps I am missing something?
For this, which may well be in the range of 10’s of amps for a contactor that large, I would imagine you could drive a solid state relay directly off Arduino, though I’ve never tried myself…yet.
Secondary question–is there a microcontroller out there similar in use/function as an arduino that is built more for industrial applications, i.e. reliable indefinite continuous sensor monitoring? Once I’ve got a prototyped solution with the arduino I’d like to build a permanent solution of similar design.
This might be what you are looking for.
DIN rail mount and all.