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# Spout's reversing circuit and final assembly

Created by Karl Wendt.

## Want to join the conversation?

• Is the yellow wire connected to the ends of both batteries on the left hand side? If so, why doesn't it form a circuit between them?
• how do you know if it's a pole or a throw?
• What does a pull and throw do?
• its a pole and throw, two throw and one pole known by SPDT it can control upto 2 terminals and DPDT can control upto six terminals. It basically helps us to switch the bateery and control the terminals
• Can someone point me to s simple explanation of how current is or is not flowing in opposite directions in the yellow wire shown in the final assembly (2nd half of this video) when only one of the lever switches is pushed. The motors will run in opposite directions because they are then using separate batteries with opposite polarity. So if you draw the conventional circuit flow for this case you will have arrows pointing in both directions along the yellow wire. I did a little digging around the web to try to explain this simplistically to my 3rd grade son, but haven't found a good explanation. thank you for your help!
• whats the diffrents between red white blue wires
(1 vote)
• Red electrical wire - indicates the secondary live wires in a 220-volt circuit, used in some types of switch legs and in the interconnection between smoke detectors that are hard-wired into the power system. You can connect a red wire to another red wire or to a black wire.

blue electrical wires - are also used to carry power but are not for wiring the outlets for common plug-in electrical devices. These colors are used for the live wire pulled through conduit. Mainly used as a traveler for a three-way or four-way switch

White and gray electrical wires - indicate a neutral wire. White is the color most often used for this function. A neutral wire connects to the neutral bus bar within an electric panel. (A bus bar is made of conductive metal that attracts the electric current for distribution outward to feeders.)

You can connect white and gray only to other white and gray wires. Although neutral, they can still carry current, particularly the unbalanced load — the electricity not being used and being returned to the electrical service.
• how does the sauder help the current
(1 vote)
• Think of the solder as a type of metallic glue. That's what it does; connects two components together.
(1 vote)
• At do your eyes have to be the same color or can you do different colors?
(1 vote)
• Hello, its me and i was wondering if that you would tell me where i can buy this?
(like to meet) this song amazing
(1 vote)
• Like what do I need to make lad lites
(1 vote)
• i don't under stand why scientists don't use this method in robot cars?
(1 vote)

## Video transcript

So this circuit combines the best of both worlds. We've got the forward and the reverse capability with this one because we added something called a "single pole double throw lever switch." It's called a "lever switch" because it's got a little lever here. And this is "single pole double throw" because there's one pole and two throws. And that's the term for these electrical contacts here. We're going to go ahead and turn our switch on, which will let power flow. You can see the motor is spinning. And if we want to back the motor up-- we want it to go the opposite direction-- we can push on this switch. And you can see it causes the motor to reverse. And what's happening is the contact inside that switch is switching from the red wire, which is the positive lead, to the black wire, which is the negative. That causes the power to flow the other direction. And if you're asking, how does it do that, well, it does that because it's flowing through only one battery at a time. So it's going through this battery in this direction under normal circumstances. And then, when the switch is bumped, it goes and flows backwards through this battery. That causes the motor to flip back and forth. Now, if we take that and we combine it with another switch and another motor, we can make the Spout turn around and go back and forth in different directions. OK. So this is the combination of all the previous circuits that we've talked about. We've got our lights, and our light switch circuit here. I believe that's this circuit. So you can see that the lights turn on when we turn that circuit. And then we have our motor circuit. And we have our two single pole double throw lever switches here. Here's another example of what it looks like on the inside. You can see there. We basically extended the switch by just hot-gluing the paperclips on to the end, and that makes it easier for the switch to bump against the wall. It also gives it some more leverage so it doesn't take quite as much force to get the switch to trigger. OK. Let's go ahead and turn it on. So you can see it's moving in this direction. It's moving forward. It'll be carrying Spout in the forward direction right now. And then, if it gets bumped, you'll notice that, when this side gets bumped, this motor backs up. And then, if this one gets bumped, this motor backs up. Again, so what the switch is doing is it's switching the power flowing from one battery-- right now it's flowing from one battery in one direction-- switches it to the other battery that's flowing in the other direction and causes the motor to spin backwards, which means that Spout can back up. If they both get hit, they both back up. So that's what's going on inside of Spout.