Why do table fans rotate in the clockwise direction, and ceiling fans anti clockwise? Is there a technical reason?
This is mainly because of the diversity in their working principles. Every fan needs a motor that allows rotational motion.Taking into consideration the structure of a motor, there are two major parts - The motor itself and the armature. Out of these two parts, one part is always stationary while the other moves around it's axis allowing rotation of any object that is attached to it.Ceiling fans have a stationary armature and the motor moves in the counter-clockwise direction. Since, the blades of the fan are attached to the motor, the ceiling fan rotates in an anti-clockwise direction.It is exactly opposite for a table fan. The motor is stationary and the armature moves to give motion to the fan blades. Because of Newton's 3 law of motion that states - "Every action has an equal and opposite reaction.", the stationary motor gives the armature a push in the opposite direction. This causes the blades of the table fan that are attached to the armature, to move in clockwise direction.Source : Difference between a Ceiling fan and a Table fan
How do you install a ceiling fan with a red wire?
If the box in the ceiling has red, black, white, and green (or bare copper), then there is a wall switch which energizes the red wire. Disconnect power at the circuit breaker box and check with a meter or test light that the black wire is hot. Also check the integrity of the white wire and the green/copper. If all is well, you have several choices:If you do not wish to have a light kit on the ceiling fan, but do wish to turn it off and on with the wall switch, connect the black wire from the fan to the red wire in the ceiling box. Put a wire nut on the exposed portion of the black wire in the ceiling box. Connect white to white and green/copper to green/copper.If you want the fan to be controlled by the switch on the wall and the light to be controlled by the pull chain on the fan, connect the red wire to the black wire on the fan and the black wire to the black wire on the light kit. Connect white to white and green/copper to green/copper. This is the most common way fans are wired.If you want the light controlled by the wall switch and the fan controlled by the pull chain, just reverse the connections, connecting the red wire in the ceiling to the black wire in the light kit, and the black wire in the ceiling to the black wire in the fan. Connect white to white and green/copper to green/copper.
Which consumes more power thin wire or thick wire?
Let us take a simple example to understand the concept. Further let us try to find out on what factors does power loss depend.Case 1:Assume you have a thin wire of 5ohms resistance & 5A current through it.Hence, total loss=(I^2)*R=(5^2)*5=125WCase 2:Assume you have a stranded conductor made of 5 identical thin wires of resistance 5ohms. These wires are also identical to that of Case 1's wire. The 5A current is now divided into 1A through each wire.Hence, total loss= Summation of individual losses =5*(1^2)*5=25WSo what we observe? The stranded conductor consumes less power than a single thin conductor.Case 3:Now if we take a single thick conductor instead of a stranded conductor, let us see what we get.We choose its length and thickness in such a way that we get its resistance as 5ohms. The formula to calculate R of a wire is,r=resistivity*(length/area)where, resistivity depends on the material and the temperature.Now assume we got R=5ohms of that thick wire.Hence, power loss=(5^2)*5=125WNow we observe that it produces same power loss that of the thin wire! So where did we went wrong? Let us have a look at the above formula to calculate r. r is inversely proportional to area. Case 3's wire has a larger area than Case 1's. So to obtain r=5ohms, either resistivity has to be increased or the length. Assuming same working temperature and material, resistivity can't be changed. Hence, length has to be increased to get r=5ohms. Now if we cut down the length of wire so as to match it with Case 1's, r drops and hence power loss drops (which is obviously less than 125W as in Case 2).So what do we learn?1. The power loss depends directly on the length of wire but inversely with the Area of cross-section.2. The power loss depends on the material we use as a conductor.3. Increase in the temperature increases resistivity and hence the power loss increases. Now, a conductor heats up as current flows through it. Hence this increases the resistivity and ultimately leads to more power loss. So to avoid this kind of situation, we either use a fan or heat sinks to cool down the system.Hope this helps :)
Light switch with three black wires - is it single pole?
All of the wires should be tested. That being said...What is likely the case, you have two wires that are in the "push down" connection and one is on the side screw. The screw connection and the "push down" connection that is beside it are the same connection. What is sometimes done in a tight box is; instead of splicing the wires together which would take up room in the box the electrician will use the side screw connection AND the push down connection and use that as a splice to carry the feed wire to another location. If this is the case When you disconnect all the wires from the switch (Take note of which wire went to each connection on the switch) you will notice that the power turned off in either a receptacle or the lights in another room. If this happens, then you know to connect (splice) the two wires that are next to each other (Push down connection and screw connection).Splice those two together with one of the dimmer wires. and then the other wire will splice to the other dimmer wire. Good Luck
How do I wire up a double switch to control two separate light sources?
The unit is two switches in one box. On the right side, there are two common (still connected) and one ground (green screw). On the left side, there are A1 and B1. Inside the box, we have two old house leads (one white, one black) and we have some new 14 gauge wire to an outlet (1 hot, one neutral, one ground). When we have everything hooked up, one switch controls the overhead room lighting perfectly as expected. When we turn on the other switch, though, it has no effect and supplies no power to the outlet. What are we doing wrong?
I HAVE 2 BLACK 2 WHITE AND 1 RED WIRE GOING INTO LIGHT SWITCH BOX. HOW DO I INSTALL LIGHT SWITCH TO CEILING LI?
Sounds like a 3 or 4 way switch. In other words a light that has more than 1 place to turn it off. That is the only reason there should be a red wire. The red wire should be a jumper. Going from one box to the other. If that is what you have, you have to have a special 3 way switch for it to work. Actually you have to have one for each place to turn it on or off. Directions are on the boxes those switches come in.
Bedroom light switch "rocker" plate got broken, is it dangerous for me to replace it myself or do I have to hire an electrician?
My son was messing around and broke the "rocker" switch that turns his bedroom light off and on. (It's one of those ~3 inch x 1 1/2 inch large, "flat" type switches.) The upper portion still work and the light turns off and on just fine, but it just looks awful. I'm getting ready to put my house on the market and have spend a small fortune doing small repairs, new paint, etc., (in other words...I'm broke at the moment), so I'm wondering if I can replace this myself or do I have to hire an electrician? I went to the store and a new rocker switch costs $10, but it will cost ~$75 to hire an electrician. The people at Home Depot and Lowes both said it's really easy to replace...but I'm not sure. My also friends told me it's super easy to change it and it only takes a few mins, and I just need to make sure the electricity is cut off to that room, but I'm a little nervous. Has anyone who is NOT an electrician changed one out? If so, was it difficult? PLEASE don't just tell me to hire an electrician, it's not an option for at least 6 weeks, it's either keep the ugly, broken one or replace it myself. Btw, I've never done any electrical work, this would be my first time. Thanks for the advice !
When trying to replace a light fixture in a very old home, what do you do when there is no junction box and no ground wire? There’s only a black and white wire sticking out of the ceiling. Picture in comment.
Wow, that’s pretty old. Be careful, and it’s best to call a qualified electrician to do this, as the insulation on these types of wire is pretty fragile and you don’t want to have them short out against each other.First of all, find the breaker which controls the circuit and turn off the circuit. Looks like you might not have a breaker in this case, however. It’ll probably be one of those screw-in glass fuses. Unscrew it, and kill the circuit.You’ll need what’s called a ‘remodel box’, which will be a blue plastic equivalent of a JB for a light fixture. You’ll have to cut a hole in the ceiling large enough to insert it and fasten it. I would use construction adhesive around the edge as well. The wire you’ve shown needs to be fished through the back of it before installing it into the ceiling.Understand that this type of fixture will not hold any real weight. It totally relies on the surrounding ceiling material for its support strength. Therefore, your new fixture needs to be the lightest one you can purchase. Or, you need a long light (like a fluorescent fixture) that you can hold up on the ceiling with anchors.Since there’s no ground wire, you’ll be hooking black-to-black and white-to-white from the existing wire to the new fixture. Use a yellow wire nut, or one sized for 12–14 ga wire. Check your work by screwing back the fuse, and testing quickly at the switch.CAVEAT — Be careful handling the old wire. The wrapped insulation fabric is quite fragile, and you do not want to be knocking it off and baring the wire. If you do, wrap electrical tape around the wires to avoid having bare spots which could short the circuit.