Selecting a PLC - General PLC Knowledge - Part 1 from AutomationDirect

hello and welcome to automationDirect Media series we're going to discuss today how to select the correct PLC or how to choose a correct PLC for your application so we're going to break this down into three parts and hope you join us for all three parts so part one we'll discuss some of the PLC's history what is the PLC just goes through some simple stuff and talk about the categories or classes okay first thing as you see here we've got some nice graphics of the PLC's that automationDirect offers here the first is a Burke unit which is the o5 I'm pointing here down at the bottom has an expandable slot and we go into that a little bit later on the next one is a 105 which has no expansion has one communication port but it has some options that people like which is a built-in DC power supply oh six a little bit bigger brick unit a lot of nice i/o here on it you can add four options slots or four option cards to it and you have two communications ports and also this optional LCD readout which is really nice 205 which is called a modular the reason why we call this modular is you buy a rack depending on size different size racks add CPU and add whatever kinds of i/o cards communications or whatever you need there same thing with a 405 and also the 305 okay get into what is a PLC a lot of customers are just getting into this they know they need a PLC somebody referred them to PLC company or referred them to us here at automationDirect and said hey you need a PLC for your application I've had customers do some odd things like maybe they just needed to add a PLC to their trying to control some lights at a art gallery or something like that PLC is a programmable logic controller just think of it as an industrial computer and it contains hardware and you use software to program it and it can perform all kinds of controlled functions I mean pretty much any type of function you could think of it could control depending on the PLC brief example let's just say you've got a light sensor or some type of sensor and a box is going down and conveyor when that box comes across the sensor you want the programmable controller to do something turn on a timer for instance for 10 seconds okay so the PLC turns on that timer after 10 seconds you want a valve to turn on and fill the box full of styrofoam peanuts so that's what it does so versus having a person stand there filling it up all day long you can actually replace that put a PLC in a quicker faster let that person go do something else a little bit more beneficial so you can also think of PLC's as things like controlling automated bottling plant think of things like amusement parks a lot of the rides and stuff are controlled with PLC's that's just some instances okay before PLC's what did we use well relays were used and to get a relay to do several different tasks you had to buy different types of relays but different sizes relays and you had to wire them them together to get these tasks accomplished you'd open up an enclosure it's probably about the size of a wall and it have all these relays tied together and working simultaneously to control machine well now you can just put a PLC in there about the size of a shoebox or smaller to do the same task brief history of PLC's is first introduced in the late 1960s mr. dick Morley of Bedford and so shi'ites presented the first modular digital controller hence the name modicon and if you've been in the PLC field you've probably heard a mano con su mnemonic on this happened in 1968 it was designed to eliminate the large costs of replacing relay based machine control I call sin these things were huge the modicon Oh 8 4 was the world's first PLC in the commercial production ok classes of PLC's Nano PLC's we call these nano because they're gonna have 0 to 14 inputs and outputs anytime you see this little IO that means inputs outputs this is your connection to the real world with devices nanos have 0 to 14 integrated io package or they're a brick often not expandable like our diello 5 is a nano but it does have one expansion slot in it next one is going to be micro it's gonna be 15 I Oh up to 128 it can be brick or modular for instance our diello 6 would be in this class small is going to be 129 to 512 getting up there in some of the i/o range you have things like expansion remote i/o and a lot of specialty cards that you could pop into the PLC and then last is going to be our large which is 512 IO and above modular i/o high densities like our 405 PLC's you have 64 point cards you can often fit 2,000 io in one local system and you can see you get into more sophisticated specialty module some that are take some brains to to program