Control Panel Build Series Part 20-Wiring the PLC

Wiring_the_PLC_Panel_Build_Series_Part_20.pdf

Wiring the PLC

Depending on the hardware that is being used, this may not be necessary other than to provide power. - Many PLC prove the option for Pre-wired harnesses that you can simply plug into the PLC - This eliminates the need to wire any of the IO to the PLC itself, you only need to wire at the terminal block side of the signal. - Some PLC do no offer this option, in which case you will need to wire the PLC manual. There are many different variations of PLC’s, and they are all wired a bit differently. In today’s video we will show you have to wire one specific type, but will provide some examples of what other PLC’s look like when wired. Understand that PLC wiring can be tricky in that the terminals are often very small, and can be difficult to work with - Make sure the wire you are using will fit I the terminals on the PLC Make sure not to fray or “birdcage” your wire terminations on the PLC - This can cause your PLC to short circuit and not function Review your drawings and the PLC manual to make sure that you are terminating wires in the correct locations - PLC wiring typically requires several conductors to be terminated to a very tight area, so It can be easy to make mistakes. Make sure to label each wire you terminate so that when the time comes to wire the terminal block side of the signal, you know what wire should go where Go slow, and take your time.

Transcript:
[0m:4s] Hi I'm Josh Bloom, welcome to another video in the RSP Supply education series. If you find that these videos are helpful to you, it certainly helps us out if you could give us a big thumbs up and subscribe to our channel.
[0m:16s] In today's video, we will move on to the next step in building an industrial control panel. If you haven't already seen the other videos in this series, we encourage to go back and watch from the beginning so that you might better understand the entire process.
[0m:29s] The step in which we will focus on today is continuing on in the wiring phase of the build but focusing on wiring the PLC and any IO modules associated with the various IO points throughout the panel.
[0m:44s] When wiring a control panel, there are most likely going to be quite a few different signal types that are included in this panel. We have already showed you how to wire those various signals such as digital and analog signals in the panel as it pertains to terminal blocks. Today, we will focus on how to wire the PLC side of the signal.
[1m:6s] Keep in mind, in many cases, the manufacturer will provide Prewired cable harnesses that have all of the wiring completed to the PLC side of the signal. This is the method that we have chosen for the panel being fabricated in this series. However, there are many cases when these prewired harnesses are not used and you need to wire the PLC as well.
[1m:31s] That is what we intend to show you in this video today. As always, the process of which we will discuss today is just one method of many that can be performed to achieve the very same results. So let's get to it.
[1m:45s] When wiring a PLC, much like the wiring with our digital and analog signals,

[1m:51s] it may not actually be necessary to wire the PLC depending on the hardware that is being used.
[1m:57s] It may be an option for the distributor or manufacturer of the PLC to provide us with a prewired harness. Like we've shown in the last few videos, these are the harnesses that we are using for this particular build.

[2m:14s] Now, again, there are many PLCs that provide this option.

[2m:18s] As well as there are many PLC that do not provide this option or also, it may be available to you, but you can choose to not use the prewired harness and to wire the the PLC yourself just depending on the situation. Some people like to use a heavier gauge wire than the harnesses typically provide,

[2m:42s] and so, in those scenarios, you would wire up
[2m:45s] the PLC yourself, so keep that in mind. Depending on the hardware you use, iIt may dictate that you need to wire the PLC.

[2m:54s] In the case of this particular video, we are going to show you how we would wire a PLC module for the PLC that we use for this particular build. Now, this is just one specific PLC module they're all very similar, at least in this particular brand of PLC. Now, there are a
lot of different brands of PLCs that are all wired a bit differently. So we're going to try to show you some images of some PCs that are wired that are done just a little bit differently than the video we have here for you today. So keep in mind that each PLC is going to be wired a little bit differently, but the concepts are typically the same, and wiring in a PLC, much like a terminal block is somewhat similar.

[3m:43s] So a few things to really keep in mind when wiring a PLC. Typically the terminals

[3m:50s] are a little bit more tricky. They're smaller and can be difficult to work with. So

[3m:57s] a few things to consider it's important to make sure the wire that we select will actually fit in the terminals on the PLC. If we use a wire that's too large,

[4m:6s] you'll find that it's very, very difficult to fit those wires into the PLC terminals and torqueing those terminals tight becomes more difficult. Also, one thing to keep in mind on some PLCs when you torque those terminals down, they don't often like to come back up as easily as say a regular terminal block. They're kind of meant to be terminated one time and left alone. So again, depending on the manufacturer that can differ a bit, but

[4m:31s] in our experience, we have found that these terminals are a bit more finicky than just a regular terminal blocks. So, keep that in mind, make sure the right wires being used and you shouldn't have any problems.

[4m:42s] Much like when we're wiring any portion of our control panel, or any wiring for that matter at all, we want to make sure that our wires are not frayed or bird caging in any way. This is really critical, especially on PLC. If there's any fraying on a PLC you're going to be really very prone to short circuiting and damaging your PLC, which is they're obviously very, very expensive.

[5m:4s] And where the terminals are typically very, very close together you're going to be more prone to these types of short circuits. And we really want to take our time make sure there's no frame or bird caging on the end of our wiring and that we're securing these wires properly and cleanly.

[5m:20s] Just like with any of the other wiring we've done throughout this entire process, we want to make sure we review our drawings often. We also want to reference our PLC manual to make sure that we're terminating the wires in the correct locations. As I've mentioned before, when we're wiring a PLC,

[5m:37s] you're going to be bringing a lot of conductors into a very, very tight area, so it can be really easy to make mistakes. So again, reference your drawings often, review your PLC manual before you really get started, and cross reference that with your drawings, just to make sure that you have a clear understanding of where every conductor goes so that we don't make any mistakes. Along with that, we want to make sure that we label each wire as we terminate in our PLCs. This helps us avoid any mistakes wiring the PLC, and it also helps us identify each wire as we go to terminate that wire on the terminal block side of that particular signal. So make sure that you label your wires as you wire them into your PLC.

[6m:25s] If you follow some of these steps and just take your time, go slow, wiring a PLC is really not that difficult, really no more difficult than wiring any other portion of the control panel.
[6m:35s] It's going to be a little more sensitive, so you want to again be cognizant of that. Take your time. You should be just fine and ready to move on to the next step.
[6m:45s] As you can see, wiring PLC modules can be difficult and requires a great deal of patience and concentration. If a mistake is made during this step, it can cause all sorts of issues later on as you begin testing your panel and functionality.
[7m:0s] Take your time during this step and you will reduce the amount of errors you could potentially encounter.
[7m:6s] As always, we appreciate your interest and participation in the series and hope you continue to join us throughout remainder of the build process.
[7m:14s] In our next video, we will wrap up the wiring phase of the build by taking time to review the work that we have done and doing some simple testing to ensure our wiring is correct. So make sure to join us next time as we continue to build.
[7m:28s] For a full line of industrial control panel hardware and thousands of other products, please go to our website. For more information or other educational videos, go to RSPSupply.com, the Internet's top source for industrial hardware. Also, don't forget: like and subscribe.