Friday, May 22, 2015

3 Way Sockets Vs. 3 Terminal Sockets

Lamp sockets come in a variety of styles, colors, finishes, materials, and flavors. Note: Don't check the flavor of your socket while the lamp is plugged in! There are seriously a lot of things to choose from, but did you know there are also different socket interiors? The socket interiors sit inside the socket shell and come in keyless, push-thru, pull chain, and turn knob. Maybe the most complicated socket interiors are the 3 way and 3 terminal interiors. Begs the question....

What's the difference between 3 Way and 3 Terminal Sockets? 

3 Way Sockets

3 Way sockets have two contacts inside the socket and are made to burn 3 way bulbs. If you look at the bottom of the 3 way bulb there are two contact points on the bulb to match the contacts in the socket. 3 way bulbs have two filaments inside the glass. The 3 way socket allows the filaments to burn independently or in tandem.

3 Way Socket Ineriors
3 Way sockets will burn a standard bulb, but there will be an extra rotation from on to off. 3 way sockets are turn knob or pull chain sockets; they will never be keyless or push-thru. Mogul sockets are also 3 way, but require a mogul bulb.

3 Terminal Sockets

3 Terminal sockets are often confused with 3 way sockets but work completely different. They are designed to run an additional circuit; mostly used for another keyless socket. They are commonly found in 3 tier lamps or Gone-With-The_Wind style lamps. 3 terminal sockets have only one contact with the bulb.

3 Way Socket and 3 Terminal Socket Comparison
 The 3 terminal socket has 3 screws on the bottom for the wires to connect to the different bulbs. The broad headed screw connects the two smooth wires from the plug wire and the other socket. The brass screw connects to the smooth plug wire and the black screw connects to the smooth wire going to the other socket.

Wiring a 3 Terminal Socket Interior
Unlike the 3 way, a 3 terminal could be a turn knob socket or be keyless socket with a 2 circuit switch. Here are some examples of the type of lamps requiring a 3 terminal socket:

If you are repairing a lamp and come across one of these types of sockets, you have just entered the next level of repair. Congratulations!

Friday, May 15, 2015

Red Table Lamp With Arm Gets Rewired

A customer brought in this lamp the other day with a classic arm and gallery at the socket. It needed a new molded plastic lamp cord and socket since it was recently repainted (candy apple red) and didn't have any hardware on it.

The first thing we do is to disassemble the lamp. Take the gallery off the threaded rod and remove the threaded rod from the end of the lamp arm. You can see the old wire still in the lamp body.

Next we take the weight out of the lamp base. Lamp weights are especially important when the materials of the lamp do not weigh enough to support the lamp or keep it from falling over. With this lamp having an arm, the center of gravity is moved away from the base so the use of a weight is most important.

Now we take the lamp body off the lamp so we have direct access to the lamp arm. The old lamp cord needs to be pulled out. It proves to be easier said than done. The old cord was quite stubborn and took many attempts (8 pulls, 4 grunts, 2 in-audibles, and 1 obvious curse word: who's counting?).

Finally with the old wire out and all the pieces separate, we can start the rewiring and reassembly of this lamp.

The new lamp cord had a molded polarized plug and for wiring a lamp that means it has to pass through each part in the right order. Make sure you have all the nuts and pieces in the right order and together. The first thread of the lamp cord is through the base. We pull plenty of wire through and then tie a knot.

As mentioned before, the cord is threaded through each lamp part in order: hex nut, leaded base, outer base, lamp rod and so on.

When you get to the arm, threading the new cord is a bit challenging. Remember the special lamp tools? We are going to use those small clamps to grab the wire from the arm and pull it out.

Next the gallery and socket cap are added to the lamp.

Next the socket interior is wired to the lamp cord. The smooth wire connects to the brass screw and the ribbed wire connects to the silver screw. The cord slack is pulled back through the arm.

The lamp key it attached to the socket interior and the socket shell is snapped into the socket cap.

The pieces of the lamp body are placed back together with the cord slack being pulled from the base. With the lamp back together and the nut screwed on tight, the knot in the base is adjusted.


Total time < 40 minutes Total Cost < $15.00

Thursday, May 14, 2015

White Bridge Arm Floor Lamp Rewired and Repaired

A customer brought in this bridge arm floor lamp the other day and wanted it to be rewired. It had recently received a fresh coat of paint and the lamp cord was cut at the base. The lamp parts needed to rewire this lamp are a new lamp cord. Note: We tested the socket and determined it was good to reuse. Things should only be tossed, canned, replaced for a reason.

The first thing we need to do is take the bridge arm off the lamp. This lamp has two swivels: one on each end of the lamp arm.

Then we remove the socket key, socket shell, and the swivel on the other end of the arm.

The lamp did not have a plug, but there was an old cord in the body of the lamp. We are going to use the old cord to pull our new cord through the lamp. First we strip the old cord and solder our new cord to the old one. TIP: Lay a lamp like this on a table top so you can stand up while you work on it.

With a good solder, we pull the new cord up the lamp tube to the first swivel. Then cut it from the old lead wire.

Then we push the new cord through the arm to the next swivel.

With the new lamp cord at the top swivel, we pull enough slack to wire the lamp socket to the lamp cord. The ends are stripped and attached to the socket interior. The smooth wire connects to the brass screw and the ribbed wire connects to the nickel screw. The socket shell snaps into the socket cap.

With the new socket back together, the top swivel gets put back in place. The cord slack is pulled back through the lamp.

The second swivel is put into position and the rest of the cord slack is pulled from the base.

Add a bulb. Plug it in. Done.

Total Time < 30 minutes Total Cost < $15.00