What is Encoder?

an encoder is a device that is used in many industries to provide feedback in the most basic terms an encoder regardless of the type which we will cover later senses position direction speed or counts [Music] before we get started on today's video if you love our videos be sure to click the like button below then make sure to click Subscribe and the little bell to receive notifications of new real Parrs videos this way you never miss another one encoders will use motion under a variety of technologies and translate it into an electrical signal that signal is then sent back to a controlling device such as a PLC and is interpreted meaning scaled to represent a value that will then be used within the program analogies involved in encoders are magnetic mechanical resistive and optical optical is the most widely used encoder motion translating technology are different types of encoders such as absolute and incremental we will describe those in greater detail in a future lesson but for now an example of an incremental optical type encoder uses a beam of light that passes through a disk that has opaque lines in a specific pattern somewhat like the spokes of a wheel on the other side of the disk is a photo sensing device that will interpret the light based on the pattern on the disk picture a shutter blocking and unblocking the light the pulses of light are then converted to an electrical signal to be sent back to the processor through the encoders output encoders have a wide range of uses which include closed loop applications such as servo or VFD control measuring and counts here are some examples of processes that may use an encoder VFD control you may be running a pump on a VFD to fill a tank full of a liquid you are requesting a certain speed and want to verify that the pumps VFD is at the requested speed an encoder on the VFD may be used for feedback of speed next let's give an example for a measuring process in this application you will need to cut some aluminum product to a particular size you are passing a long roll meaning hundreds of feet of the aluminum sheet through a cutting mechanism you need to determine the amount of aluminum fed so that you can cut the sheets to the proper size that will be used in a separate manufacturing process an encoder attached to the conveyor and reading the material that is feeding through your cutting assembly will indicate the length of material that has been fed since the last cut that feedback can then be used to adjust the cutting blade to sever the length required for an example of counts consider this process you have a conveyor line that has bottles running on a conveyor they are counted by a photo I sensor when entering the assembly they have a cap with an aluminum tamper proof foil on top that needs to adhere to the bottle once the foil is sealed the bottle will then move down the conveyor line and verified that it exited the cap ceiling assembly via and exit photo I sensor some of the requirements for this station are the same number of bottles that enter the assembly must exit in a predetermined timeframe the bottle must not remain in front of an entrance or exit sensor the bottle must not be exposed to the inductive sealer longer than a predetermined amount of time you must make this assembly flexible enough to handle many types of bottles and entrance and exit sensor placement consider a prescription bottle easy right no handles just a bottle that is a standard size now consider an antifreeze bottle with a somewhat small cap and a very large handle how in the world are you going to meet the requirements for the machine and remain flexible if you put a pill bottle in yep easy peasy right bottle in seal bottle out no censors blocked if any of the requirements fail bottle in seal tips over and isn't counted out Machine halts and alerts on operator of a malfunction how about the antifreeze bottle bottle in cap passes in front of an entrance sensor bottle counted then the handle the system faults because it sees a blockage at the entrance how do you tell the machine that this is expected behavior an encoder of course and a selector switch for a set up mode setup insert your product in this case the antifreeze bottle you make sure to feed cap first and it must contain a foil your program reads an entrance on the sensor and records an encoder reading as well as determines that this is a cap and records that fact your program then reads another entrance and determines that this is not cap it must be some other acceptable part of the bottle possibly a handle the single bottle continues down the line where the exit sensor is triggered at that point you again record the encoder value you now have an encoder count that registered at the entrance and exit in the code you subtract the entrance from the exit and you have a bottle count you now know precisely how long it will take that bottle to move through the system meeting thee must enter an exit in a predetermined timeframe in this case encoder counts you have also made the flexibility aspect of different types of bottles as well as being able to place the entrance and exit sensors any reasonable distance apart when back in run mode the code knows that there's a handle to ignore when it comes into the process and doesn't fault a machine you register the encoder at each bottle entrance and predetermine when the bottle must exit if the bottle doesn't exit the machine in a timely manner which is based on your projection and the current encoder count the Machine faults this is a great use of an encoder that is fully configurable count in count out subtract done don't miss the next lesson where we are going to discuss incremental and absolute encoders want to learn see programming in an easy-to-understand format and take your career to the next level head on over to real parse com [Music]

Channel: RealPars

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Keywords: Encoder, Absolute Encoder, Incremental Encoder, Encoder Technologies, Optical Encoder, Magnetic Encoder, Mechanical Encoder, Resistive Encoder, Encoder Types, Encoder Applications, Encoder Feedback, VFD control using Encoder, Measuring with Encoder, Counting with Encoder, Encoder Output Pulses

Id: k2GQVJ4z0kM

Length: 8min 40sec (520 seconds)

Published: Mon Mar 04 2019