Posts tagged: circuit

Short Circuit vs. Ground Fault

By admin, June 10, 2012 2:36 pm

When a fuse blows or a circuit breaker trips, was it a short circuit or a ground fault that caused it? To the average do it yourself electrician, it’s hard to tell by going to the fuse box or electrical panel. You open the fuse panel only to see a fuse blown, but that’s no clue. Likewise, you go to the circuit breaker panel and see a tripped breaker, but why?

To help explain what happened, we first need to be familiar with the two terms; short circuit and ground fault. A short circuit occurs when a “hot” wire and a “neutral” wire actually touch each other. When this happens, a large amount of current flows, causing a fuse to blow or a circuit breaker to trip, not to mention the sparks and pop that is followed generally by a little smoke. online slots .

The cause of this unfortunate occurance may be as simple as a loose connection on one of these two wires nder a ternimal in a junction box. online casino . A wire slips off of under a terminal and lands in contact with the other wire. Sometimes, an appliance encounters an electrical problem and wires touch that were not meant to. And then there’s the sneaky critter, the mouse, that chews the wire insulation and causes a short circuit between wires run in a bundle.

When a short occurs, a large current flow through a fuse or circuit breaker will open the circuit, blowing the fuse or tripping the breaker. Looking through the sight glass of the screw-in fuse (plug fuses), you’ll notice a blackened glass if the fuse was blown. In the case of a cartridge fuse, there is likely no physical sign, as this fuse is concealed. But you can test it out of the circuit with an ohm meter or continuity tester to see if it is blown.

Now as for a ground fault, that occurs when the “hot” wire comes into contact with the ground wire or a grounded portion of a junction box or grounded part of an appliance or device. Similar to a short circuit, large amounts of current are forced to flow through the fuse or circuit breaker, causing a fuse to blow or a circuit breaker to trip. In the same way as the short circuit, you will be hard pressed to learn the cause without doing a little investigating on the circuit with the trouble.

As you may or may not know, some fuse can only handle the current capacity they are valued at, like 20 amps for a 20-amp fuse. However, and this may be the confusing part for some of you, some fuses are designed to handle a temporary surge of current beyond their rating for a short period of time, called time delay fuses. These are great for appliances and motor driven devices that normally need a larger cuurent to get a motor or pump turning, but then require less to keep them running, thus this fuse suits the purpose well.

As for short circuits and ground faults, we don’t want either, but with the use of protective devices like fuses and circuit breakers, we can rest easy knowing that we have electrical safety devices guarding us at all times. Electrical shorts and ground faults can be caused by working on a circuit that wasn’t turned off first, hopefully not, but it can be no fault of our own.

So the next time you wonder why your fuse blew or breaker tripped remember, the important thing is to have protective safety device in place to save both devices and the wiring throughout your home.

NEW WEBSITE Ecomatic Calculate energy in a SUSTAINABLE way.

By admin, January 26, 2012 10:32 am

Thursday, Jan 26, 2012

Top Cable has developed an innovative measuring tool called Ecomatic which calculates how much energy you save in electrical installations.

Sustainable development is part of Top Cable’s strategy, as shown by their commitment to controlling and reducing their impact on the environment. Strengthening this commitment, the Ecomatic programme calculates the energy that you can save choosing a cross-section that is greater than what is strictly necessary for your installation. A greater conductor cross-section reduces the circuit’s resistance, decreasing Joule losses and optimising the use of energy.

Ecomatic gets you significant energy savings, with a subsequent drop in the electric bill and a considerable reduction in CO2 emissions in the atmosphere. casino online . It is a highly useful tool for engineers, installers, distributors and students.

Source: Top Cable

Christmas Lights Go Out

By admin, November 16, 2011 8:59 am

Ah yes, it’s Christmas time again! Time to decorate the tree with garland and Christmas lights. The glow of colored lights glistening throughout the house while waiting on old St. Nick. But what happens when the lights suddenly go out? Is Rudolf stealing the power to light his nose? Is there a power outage? Well don’t get too excited yet. Let’s examine what some of the probable causes are and how to remedy the problems.

  1. Check the Circuit Breaker or Fuse Feeding the Circuit

    Go to the electrical panel and check to see if any circuit breakers are tripped or fuses blown. Use a circuit tester to see if the outlet that the lights are plugged into is hot. If not and the circuit is on, turn the circuit off, remove the outlet, and check the connections to the outlet.

  2. Check the Fuses in the Christmas Lights

    If the Christmas lights go out, it may be as simple as a fuse blowing within the light set itself. Located within the plug-in plug is a couple of fuse. They are hidden behind a sliding door that is clearly marked. Simply unplug the lights and slide the cover to expose the fuses. Remove the fuses and check them with an ohm meter. If there is no resistance, they are good, but if there is infinite resistance, they are bad and should be replaced.

  3. Check the Individual Light Bulbs

    Sometimes the Christmas light bulbs themselves are the troublemakers. They could be loose in the sockets and that can cause them not to light. A bulb could have fallen completely out of a socket or have a bulb wire bent to the side that isn’t making contact with the socket contacts. Usually you’ll have some replacement bulbs that come with the lights for just such an emergency. Replace the bulbs if needed.

Electric Heater Dangers

By admin, November 12, 2011 11:38 am

As the extreme cold snap takes a grip on your area, many times people are tempted to plug in portable electric heaters to add a little extra heat to rooms. Portable electric heaters are a nice addition to heat these rooms as long as you don’t get carried away. The problems start when you connect too many heaters to the same circuit and cause a circuit overload. By overloading the circuit, the electrical wires and connection will heat up and trip the circuit breaker or blow the fuse it is connected to. Obviously there is a problem, but too often, people will just go and reset the breaker or change the fuse. If you reset a breaker too many times, it’s likely that you’ll weaken the breaker and have to cable manufacturerschange it.

These devices are just doing their job and you’re just setting them up for failure if you don’t find the problem. In fact, you’re likely headed for an electrical fire in your home if you keep resetting the breaker or changing the fuse, especially if you install larger fuses than were in the fuse box to begin with.

As you can see in the pictures, the electrical wire insulation breaks down and burns and that in turn causes the wooded walls to smolder and eventually catch on fire. This family was very fortunate that the home didn’t burn down due to the smoldering wire and wood. Luckily, the fire department came just in the nick of time to save the home, but not without a cost. The home now has to be remodeled and the electrical wiring has to be updated and changed, not that that’s not a good thing. Luckily this happened in the middle of the day while they were all awake and able to see the smoke. If they had been asleep when this had happened…who knows?

And while we are on the subject, have you changed your smoke detector batteries lately? Do you have cable manufacturerssmoke detectors in and around sleeping areas of your home. Are they cable manufacturershardwired so that if one goes off, they all sound an alarm? If not, this may be the time to get prepared for a fire in your home.

To avoid electrical fires in your home, be sure that all the electrical connections are tight. Make sure that cord are plugged all the way into an outlet and that that connection is secure. Too often, outlets become worn and they loose their tension strength. This causes the cords to fall out or hang half out from the outlet. This in turn is like adding a resistance to the circuit and causes it to heat up. And of course, you know the rest of the story. Electrical safety is a 24-hour, seven day a week job. Practice cable manufacturerselectrical safety everyday and it will become a routine, not a chore!

Middle-of-run Circuit

By admin, October 15, 2011 10:19 am

Wiring Typical Laundry Circuit

By admin, September 26, 2011 10:31 am

It is commonplace for homes today to have one or more of three different laundry circuits. Each has its own unique assignment for supplying power to the laundry appliances. One is a 20-amp circuit designated to run the 120-volt power for the washing machine and the control power for the dryer. This circuit can also supply general-use devices. It is wired with 12-gauge wire and is usually type THHN or THWN wire. This is a dedicated circuit for the laundry room only.

The second is a 240-volt outlet that supplies a 30-amp circuit to feed an electric dryer. This circuit is wired with 10-gauge wire and is also THHN or THWN type wire. This feed is exclusively for and electric dryer and nothing else.

The third is one you may not have thought of. What would a laundry room be without a circuit for lighting? The lighting circuit may not be an independant circuit, and in fact, usually isn’t. It is likely it will be on the same circuit as an adjacent room or hallway.

With the following electrical wirng tips, you’ll be able to add an outlet, install a dryer outlet, or install a single-pole switch in no time.

How To Wire An Outlet

How To Wire A Dryer Outlet

How To Wire And Install Single-pole Switches

What is Grounding and How Does it Work?

By admin, September 15, 2011 9:26 am

Grounding is a method of giving electricity the most effect way to return to the service panel. You see current flows from the panel to the outlet or device to power it up. The neutral wire is the return path for unused current. The ground wire is an additional path for electrical current to return safely to ground without danger to anyone in the event of a short circuit. In that instant, the short would cause the current to flow through the ground wire, causing a fuse to blow or a circuit breaker to trip.

An ungrounded electrical box, appliance, power tool, or extension cord could become a danger if there is no path to ground, except through you. You see, without a ground wire, your body may complete the ground path and you may be shocked or electrocuted.

A properly grounded circuit has boxes, devices, and service panel grounds that give the electrical current the easiest path to ground and that reduces the chances of someone getting a shock or getting electrocuted. Household electrical systems are required by the National Electrical Code to have a grounded system connected to earth ground via a ground rod. The earth absorbs the over-current or short circuit harmlessly and having done so, eliminates the threat to anyone that may have otherwise been the ground path.

But ground rods and ground wires to boxes, devices, and service panels are not enough. You must remember to bond the grounds to the house’s copper water lines. You certainly wouldn’t want a short circuit to travel through the water pipes while you’re in the shower, bathtub, or using a sink. Remember that water and electricity don’t mix!

And while we’re on the subject of grounding, I’m often asked if using a receptacle adapter is OK. First of all, I’m not a fan of doing something half way. I’d rather change the receptacle to a grounded receptacle and have the ground wire connected to the receptacle and the box. Although you can use an adapter and connect the center cover-plate screw to the adapter to gain a ground if the box is grounded, it just seems like a skimpy, lazy way to fix the real problem, the need for a new receptacle.

Receptacles that have only a hot and neutral slot are called polarized receptacles. By having a smaller hot wire slot and a larger neutral slot on a polarized receptacle, the electrical current flows the appropriate way through the circuit. For safe use of these receptacles, double-insulated power tools can be used in polarized receptacle circuits. These safety features can reduce the risk of electrical shock, but once again, my advice is to replace the receptacle and rewire if needed to convert the circuit into a properly grounded circuit and receptacle.

Testing Receptacles For Ground

By admin, September 15, 2011 9:26 am
It is important in this day and age to have a ground on the receptacles in your home. You likely have on of two types of receptacle, a polarized or a three-slot receptacle. In order to perform this test, you’ll need some type of electrical tester. This could be a neon tester, a receptacle tester, a voltage tester, a receptacle tester, or a multi-meter. Let’s take a look at the testing procedures for both polarized and three-slot receptacles.

1. Polarized Receptacle Power Check

When testing a polarized receptacle, first check for power to the receptacle by placing the red lead of the tester in the smaller slot and the black lead into the larger slot.  If the tester lights, you have established that the receptacle is powered up and you can continue testing.

2. Polarized Receptacle Center Ground Screw Test

Once you verify that you have power, remove the black lead and touch it to the screw in the center of the cover plate.  If the tester lights up or registers, the outlet is grounded and wired correctly.  If not, continue to the next test.

3. Polarized Receptacle Reversed Wiring Test

Place the red test lead into the long slot and the black lead on the center screw of the cover plate.  If the tester lights, you have established that the receptacle is wired incorrectly.  The hot and neutral wires are reversed and should be switched to make a correct connection.

4. Polarized Receptacle Absence Of Ground Test

Now try placing the black lead on the screw in the middle of the cover plate and place the red lead in each of the other slots (small and large slots) to see if the tester lights.  If it doesn’t light for either, the receptacle isn’t grounded.

5. Three-Slot Receptacles Power Test

In order to test a three-slot receptacle, check for power between the large and small slot.  Place the red lead into the small slot and the black lead into the larger slot.

6. Three-slot Receptacle Center Ground Screw Test

Once power is established, take the black lead out of the large slot and move it to center screw of the cover plate.  The tester should light if the ground connection is good and the receptacle is connected properly.  If it doesn’t light, continue to the next test.

7. Three-slot Receptacle Reversed Wiring Test

Place the red test lead into the long slot and the black lead on the center screw of the cover plate.  If the tester lights, you have established that the receptacle is wired incorrectly.  You can also place the red lead in the small slot and the black lead into the round slot.  If the tester lights, you have once again found out that the hot and neutral wires are reversed and should be switched to make a correct connection. 

8. Three-slot Receptacle Absence Of Ground Test

Now try placing the black lead in the round hole and try placing the red lead in each of the other slots (small and large slots) to see if the tester lights.  If it doesn’t light for either, the receptacle isn’t grounded.


9. No Power On The Receptacle

If there is a case where there is absolutely no power on the receptacle at all, you have another problem.  It may be that the wiring from the circuit breaker or fuse is damaged and not completing the circuit.  It may be a circuit breaker has tripped or a fuse has blown. In these cases, you can reset a breaker or replace a fuse if the the circuit looks to have no visible defects.  It is likely, however, that something caused the tripping of the breaker or blowing of the fuse.  Try unplugging everything connected to that circuit, reset the breaker or replace the fuse, then one at a time, pluf the devices back into the circuit to find the problem, if any.

Electrical Basics 101

By admin, September 10, 2011 8:43 am

A breaker panel consists of a main breaker that is sized according to your homes’ load needs. It is used to turn the power on and off to the entire electrical panel. Typically, homes have a 100 amp or a 200 amp service.

A main breaker of 100 amps will only allow 100 amps to flow through it without tripping. In a tripped state, no current will flow throughout the panel. It is the interrupt between the service and the branch circuits of the panel.

This main breaker protects the main service wires from damages that would occur given an overload. In that case, the wires would heat up and eventually could cause a fire.

  • Introduction
  • Electrical Service Connection
  • Disconnect Switch
  • Main Breaker
  • Branch Circuit Breakers
  • Switches
  • Outlets
  • Wiring


Single-pole Circuit Breakers

By admin, September 9, 2011 3:56 pm

The standard for circuit breaker panels is either single- or double-pole circuit breakers. Single-pole breakers are an important part of electrical distribution as a safe way to manage branch circuits from a circuit breaker panel. Single-pole circuit breakers supply 120-volt power to circuits, while double-pole circuit breakers supply 240-volts to circuits. Single-pole breakers come in a wide range of amperage ratings, with 15-, 20-, and 30-amp circuit breakers being the most commonly used in most household installations.

These circuit breakers come in different shapes and sizes, depending upon the manufacturer of the circuit breaker box. Single-pole breakers supply and protect 120-volt branch circuits from the service panel. They have a handle to manually turn the circuit breaker both on and off. This handle has a specific amperage labeled on it that is the maximum amperage allowed to pass through the circuit breaker before it trips.

Single-pole circuit breaker is designed to trip if the amperage rating labeled on the handle is exceeded. This occurs when the circuit is either overloaded or a short circuit occurs somewhere within the branch circuit that it is connected to. An overload occurs when too many things or to great a load is connected to any one circuit. A short circuit occurs when the hot wire is forced to connect to either the neutral or ground wire within a circuit. It could be a motor winding shorting two wires together or as simple as a hot wire falling off of a terminal within an outlet box and hitting the ground wire.

Single-pole circuit breakers supply many things throughout the home including general lighting, outlets, furnaces, electric baseboard heaters, fans, all types of 120-volt appliances, curling irons, hair dryers, vacuums and many other everyday 120-volt electrical appliances. But the list doesn’t stop there. They control outdoor lighting, electronic devices, air conditioners, and those power tools many of you use in garages and out buildings.

So you see, single-pole circuit breakers are a very important part of your overall electrical circuit protection safety devices and they do their job very well. Many single-pole circuit breakers have a clear peep sight that shows red when the circuit breaker has tripped. This along with the handle moving to a center position gives you a clear indication of which breaker has had trouble on it. The nice thing about circuit breakers is that they can easily be reset from a tripped state.