 So motor control overloads is what we're talking about today. Now there's a difference in overload and overcurrent. An overcurrent sense is a rise in current outside the normal path, and I'll show you a picture of that in a second. It usually happens very, very quickly and the amperage is gigantic. So think short circuit is basically what an overcurrent is. We use fuses to take care of that. Now overload sense is a rise in current inside the normal path. Let me show you a couple of examples. This kid here, you've all seen the meme about how he's going places, not college, but places. There's a dead short, so he's going to end up getting fried from that, and he's going to blow a fuse or a circle breaker. This is an example of an overload where you have people plugging way too much into a breaker and it ends up tripping. The same thing applies with motor control. A motor itself will get overloaded, and it will end up causing the current to rise slowly to a point where it's dangerous, over 125% of the rating of the conductor. And then we have an overload heater that senses that in trips. So let's just take a look at our overload heaters here. Now overloads have to have some sense of, or means of sensing the motor current. They have to have some sort of time delay in there because when you start a motor, you can have an inrush current, so you have to make sure that your overloads don't trip right away. It could cause nuisance tripping. Again, I'll go way more into detail during the course. And they are divided into two sections. You have your heater section, one that actually senses the current going through the power circuit, or and the contacts. So that kind of opens up the control circuit. So when we look at this, here I've got, these are the heaters right there. And right down here are the contacts, and they're attached to each other. So when these guys open up, these guys trip. So let's look at the two different types. There's thermal types of overloads, and then there's magnetic type. And I'll just go a little bit into them. You've got your solder pot and your bimetallic strip when you're dealing with the thermal type of overloads. Now solder pot, this is an example of the solder pot wheel right here. You've got your main power coming in. Say this is coming from the motor or coming from supply going to the motor. So current goes through here all as well. This box around here, and I should change the color in this, which I will do for the course, is like a zinc alloy melting alloy. So what'll happen is if it heats up, it'll become more viscous, which means it'll become almost liquidy. And right now you've got this guy here. These contacts are to the normally closed contacts, pushing up, there's this arm here, pushing on this wheel. And it's being held in place by the zinc alloy. If this ends up getting to a point of melting, this spring tension will push up against it. And boom, your normally closed contacts open. So you've got your power circuit up top here and your control circuit along the bottom there. So that's how your solder pot overloads work. So there's an example of what a solder pot looks like. And again, I'll show you an exploded view of that in the course. The bimetallic strip is just basically two different types of metals, brass and steel or whatever. They heat up at a different rate, which causes them, because they expanded at a different rate, it causes this to bend. And with this beautiful picture I've drawn, shows here it's bendy. So what it looks like is if you've got power coming in here, power coming in, going through here and going out, there's my normally closed contacts. So power comes through, goes out. If this heats up, it bends up, like we saw in our last drawing. And boom, the contacts open. So an example of a bimetallic strip. Now magnetic overloads are pretty cool. These guys you see tease, which is just a current transformer. So you bring your lines coming down there, there and there. And then you can use solid state basically. So it's sensing current as it passes through there. And just like your clamp on ammeter does, and you can set these things up. I've used these motor logic plus ones at a time. They are awesome. So you can reset your envelope by pressing this. You can program there's so many different variables. You've got some contacts here that you can use to set off alarms, turn on lights, whatever you want. Very, very robust, very, very awesome. And they're not affected by ambient temperature at all, which is nice. Again, I'll go into some of these settings in the course. But just to give you just the basics, you've got just your line one, line two, line three coming in here, going through the donut type current transformers sensing current. And then if you go over that, then you've set your program in here to a certain amount and it will trip when it sees that. This is a dashpot type, which I will talk way more about when we get into timing circuits. And I do this, the module on timing when we get into the motor control section. But again, you have your normally closed contacts here. It works off of the principle of magnetism as well. So you've got this coil here. You've got this shaft, you're dang right. And you've got this orifice hole, the orifice and the piston, which is just this bar across here. The piston needs to pull up through this oil. The green part is the oil. And so what happens is as this coil is sensing current, if it increases, it magnetizes, which wants to pull the shaft up into it like a solenoid plunger. When that happens, if it happens, it pushes this push rod up, which will open up these contacts. And that's how the dashpot works. It's an older timing circuit as well. But again, I will go way more into that and create a detail in the timing module.