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Current time:0:00Total duration:2:48

Video transcript

okay so we're going to take a look inside of the single-pole double-throw lever switch so we have one pole right here and two throws and what that basically means is that we can connect to three different locations on this switch and control the power and two circuits so we're going to take a little small watchmakers screwdriver and pry open the housing okay so this is the inside of our lever switch you can see it's all taken apart for us and they are their two contacts here there's one con there's one pole here and two throws and so what that means is when the switch is open it can let the power flow in one circuit when it's closed it can let the power flow in another circuit or it can just close that circuit so you can see what happens is there's a little tiny plastic hammer here that pushes against a spring so the lever causes the spring to push down on this copper connect contact and that is switching between this side and this side so the switch is basically opening and closing the circuit between this side and this side and then between this side and this side so if you watch carefully you can see that little copper contact shifting up and down I believe these pieces are made out of aluminum it looks like the spring is spring steel well looks like we have the lever here which is probably nickel-plated steel looks like and we have a copper contact that the spring is connected to and I think the housing is made out of ABS and again that's an injection molded housing you can see that it's it's got these little these little spikes here that stick up I'm not sure if you can see that too well but there's little spikes there and they basically go through the top of the housing here in these little tiny holes so if we put this like this that's how it goes and those little tiny spikes will stick through those holes and then what they'll do is they'll take a hot plate or a hot piece of steel and push it against those those spikes that are sticking through and they actually mush down like a mushroom on top of the top of this and hold it in place and so that's what the top of our single-pole double-throw a lever switch how it's held in place and again that's a looks like an injection molded piece as well so again when we push on the lever switch it switches between this contact this contact is is always connected but it switches between these two contacts so there's single pole this is the pole and there's two throws so you can see these two throws are there and when the switch gets bumped switches between those throws