I'm on a work assignment to replace some old hardware, a TECO SG2-20HR-D.
http://www.factorymation.com/Products/F ... 0HR-D.html
We're using it for a very basic application, sensing 2 pressure switches (GEMS PS75) and actuating one of 2 contactors to power a solenoid A/B valve for forward/reverse in a hydraulic circuit. This is on a large wood grinder, it uses a hydraulic ram to feed material.
Here is the current setup:
Here is what I think could work, by replacing the SG2 with an RPi+3v3/5v conterter+24V relay:
Does this look like it could work? Sorry for the childish graphic but I'm not an electrical engineer and don't have any circuit software.
Also, my boss wants something "plug and play", without any soldering or breakout boards. Ideally something that accepts 5v or 24v hi/lo inputs, can send 24v output, and interface via USB with the RPi. Any suggestions?
This might work? But for $275 instead of about $20. the USB-4761: http://www.bb-elec.com/Products/Remote- ... dules.aspx
UPDATE: I found a board from Karlsson Robotics that should work out.
http://www.karlssonrobotics.com/cart/us ... hannel-io/
4 relays with 5A 110Vac / 24Vdc
6 configurable I/O