Posted 6 Feb 2018 Good evening(here at least), I am working on a senior design project that requires the use of a PLC. Due to budget we've had to settle for an older Micrologix 1000 from Allen Bradley. I've managed to get the software running and connect with the programming port. The problem I have right now is trying to decipher how I would connect a load cell(Such that it causes a condition change at a certain weight). Ideally I would want a load cell amplifier connected to an analog input, but I don't think the 1000 has support for that. Would it be possible to use something like the HX711 amplifier(digital output) to be read on one of the input pins of the micrologix? I wanna say the pins don't read a pulse modulated input and I can't seem to register for the AB knowledgebase as the site gives me a web error. I'd appreciate any feedback. Thanks in advance. Share this post Link to post Share on other sites
Posted 6 Feb 2018 Unless your senior design project expects creativity, with control systems, when given a task, answer: Question #1 What similar solutions have other people implemented? There is no need to re-invent the wheel. With any I/O device, that device has a communication protocol (i.e., discrete or analog, 120VAC or 24VDC, PNP or NPN [sink or source], 4-20mA or 0-10V, etc.). First, get a handle on what I/O this PLC supports. There are many MicroLogix 1000 variations with a variety of I/O. Since the teacher/professor has selected the processor, this is what you have to work around. Refer to pg. 41 http://literature.rockwellautomation.com/idc/groups/literature/documents/sg/1761-sg001_-en-p.pdf Next, if your load cell requires an input type that this PLC processor does not support, does the PLC processor allow for expansion modules? http://literature.rockwellautomation.com/idc/groups/literature/documents/um/1761-um003_-en-p.pdf Share this post Link to post Share on other sites