SAFE INSTALLATION ELECTRICAL AND SERVICE PANELS IN RESIDENTIAL CLOSETS

This month’s column discusses contentious issues and topical topics that usually resurface in NECA’s online “Code Question of the Day.” The columnist shares his opinions through his responses and welcomes feedback on the topic covered. Give your thoughts via email.

QUESTION: Can a service panel for a residence be installed in a walk-in closet? Section 240-24(d) is unclear on this.

ANSWER: According to section 240-24(d) of the National Electrical Code (NEC), which specifies that “Overcurrent devices shall not be located in the vicinity of easily ignitable material such as in clothes closets,” you are not permitted to do so. This section doesn’t distinguish between one clothes closet type or another. This is further confirmed by the denial by the NFPA code-making panel of a proposal for the NEC 1999 edition, which demanded an exception to 240-24(d) to read: “If the working clearance room specified in Section 110-26(a) is met, panels shall be allowed in walk-in closets.” The reason for the proposal was that “Jobs would no longer fail if sub-panels are placed in walk-in closets”. This exception would also address the option of challenging sub-panel positions to satisfy Code requirements, especially in large custom homes. “In opposing this suggested revision of the NEC, the panel statement reads:” A walk-in closet is designed for storage of materials, many of which may be easily ignitable, and installing overcurrent devices in this area woud constitute a hazard. There’s no way to control how this space would be used since it has been designed for storage, even in a big custom home. “Author’s remark: Actually, walk-in closets are designed to store items, many of which can easily be ignited. But as far as constituting a threat is concerned, we no longer talk of mounting fuses in a wooden cutout box in porcelain fuse tubes. Currently, overcurrent systems are enclosed in metal enclosures, which would have me curious about other places if not deemed worthy of living in a walk-in closet— in fact any place where panels are permitted. Should we say that store spaces, basements, garages and basement do not contain items that are easily ignitable? The only point to note here is that of “proper clearances.” I would doubt the logic behind installing panels in a single-family home in any sort of closet, but there may be conditions under which this may seem like a reasonable solution.

QUESTION: Often, installing electric panels in apartments or condominiums is a challenge. What’s amiss with setting up a panel in a walk-in closet or a clothes closet?

ANSWER: Let’s do a bit of research on this issue, because it’s always coming up. According to the 1975 edition of the NEC, the position of overcurrent protection equipment was called “Location in Premises” and was contained in Section 240-16(c), which states, “Not in the vicinity of easily ignitable materials.” This provision was moved to Section 240-24(d) in the 1975 edition but the terminology stayed the same. For the 1981 NEC, a proposal was introduced for a new subparagraph (e) of Section 240-24 which reads, “Overcurrent devices shall not be located in clothes closets.” The substantiation for this proposal reads as follows: “The practice of panels (overcurrent protection) in clothes closets in my opinion creates a hazard as much as, if not more than, a fixture not properly installed per Code. For occupancies of the form of home, closets are lined with panel-covering garments, and are also behind closed doors. With the use of several panels (overcurrent protection) mounted in the closets of the building, renters are unable to quickly reset their GFI to the bathroom (if a breaker is used). Locating overcurrent protection in wardrobes contradicts 110-16, 422, and 440-14. “(This information is presumably taken from the 1978 edition of the NEC, which was in effect at that time.) The unanimous vote of the Code panel on this amendment plan was’ Accept as revised.’ The revision of the panel added the words ”such as in clothes closets ” to Section 240-24(d). And what did 240-24(d) mean? Indeed, it forbids the installation of overcurrent equipment near easily ignitable items. Author’s Comment: First, I can not believe the following substantiations:* “Panels in closets create more hazard than a fixture not installed per code.” * “Closets are filled with clothes covering panels and they are behind closed doors.” “Tenants are unable to reset their GFI for bathrooms quickly.”* “Overcurrent protection devices in closets violates 110-16, 422, and 440-14.” There is not a single comment about the substantiation for this proposal in the panel statement. One public comment was made calling for revocation of the panel decision. The substantiation for this submission read: “The only appropriate action to be taken on this proposal is to delete it on the grounds that it has been in the Code since the days when it was common practice to install fuses in porcelain fuse holders in a wooden cabinet. The law once made sense, but now it doesn’t make sense, because all overcurrent systems are now in metal cabinets. As a panelboard location, the clothes closet is not especially preferred, but there are few other places within a dwelling unit that are aesthetically pleasing to architects or inhabitants. The clothing in a clothes closet can be changed quickly and easily. The panel recommendation will not improve safety.” This public comment was rejected with the panel assertion “CMP-4 believes safety will be enhanced by the acceptance of Proposal No. 19.” Indeed, this occurred 20 years ago and it is still with us today. No requests to amend Section 240-24(d) were presented during the latest NEC review process of 2002, implying we can continue to operate for the foreseeable future under the existing NEC language of 1999.

THE SYSTEM OF OPERATION OF THE TRIP UNIT OF A CIRCUIT BREAKER

A circuit breaker is ordinarily expected to provide a means to manually open and close its contacts. However, whenever it senses an overcurrent, it is also expected to open its contacts.

This function of the circuit breaker is determined by its trip unit.

For a circuit breaker of thermal-magnetic characteristic, the design of the elements in the trip unit are such that it senses high current which results from situation of short circuit and also, the resulting heat which occur in states of overloading. There’s also the some circuit breakers of thermal-magnetic properties are incorporated with buttons for “PUSH TO TRIP” purpose.

Manual Trip

Some larger breakers could be tripped manually with the incorporated “PUSH TO TRIP” button which is on the surface of the circuit breaker. The tripper bar rotates upwards and to the right whenever the button is pressed.

The contacts are opened by the operating mechanism.

Overload Trip

Overload states are sensed by circuit breakers of thermal-magnetic properties. These circuit breakers have bimetallic strips which sense the states of overload. When there’s ample overcurrent flowing through the path of the current, this leads to the buildup of heat and the subsequent bending of the bimetallic strip.

A bimetallic strip is composed of two distinct metals which are bonded together. Due to the difference in their thermal expansion properties, the bimetallic strip bends when heated. A rise I current gives a commensurate rise in heat.

The bending of the bimetallic strip depends on its degree of hotness. The removal of the heat source (opening of the contacts of the circuit breaker) leads to the cooling of the bimetallic strip and its return to its original state. This provides for manual resetting of the circuit breaker once the overload state is corrected.

Short Circuit Trip

As described earlier, the flow of current across blow-apart contacts of a circuit breaker produces opposite magnetic fields. Such opposing forces are not adequate for splitting the contacts in normal conditions of operation. However, when a short circuit occurs, those opposing forces significantly increase.

The conductor that passes close to the trip unit of the circuit breaker has the same current as the one flowing through the contacts. Sufficient force is provided to open the trip breaker and the trip unit by the magnetic field at fault current points.

A sudden interruption of the fault current happens as a result of the joint activities of the magnetic fields which forces the contacts to be apart while at the same time trip the circuit breaker.

Trip Mechanism

The trip mechanism, which is in the trip unit has the tripper bar which holds the mechanism firmly in position. The mechanism will always be locked in position as long as it is held by the tripper bar.

The trip mechanism holds the operating mechanism in the “ON” position. The activation of the trip releases the trip mechanism and so the contacts are opened.

CLEARANCES IN THE PANEL OF A CIRCUIT BREAKER

For safety reasons most especially when they’re to be worked on, electrical panels need to have space around them.

Empty spaces needs to be around electrical panels; for safety reasons when they are to be worked on. Know more about those clearances.

The required working clearance around an electrical panel

Imagine seeing your most loved refrigerator; the amount of space the refrigerator would ordinarily need is just about the same as the working clearance you would need right in the front of an electrical panel. Let’s look at the ABCs; the actual working space and the path to getting there. These are basic requirements. The working space having a depth of 36 inches. And at least, the width of the working space being 30 inches or of the panel, whichever one is greater. The panel, however is not required to be centrally positioned on the working space. It could   be on any of the sides. The panel door must be at least be able to be opened at an angle of 90 degrees, so this must have been factored into the working space. The working space must be of height 6-1/2 feet.

The protrusion of the other electrical equipment which are on the top or under the panel cannot be more than 6-inches from the front of the panel. And the space which is equal in depth and width of the panel which extends from the structural ceiling to the floor is meant for electrical equipment; this means there’s no room for ductwork, gas pipes or plumbing or any foreign equipment. The clearances are put in place for the sole purpose of protecting anyone that might need to work on the panel. With your hands pinned to your sides, it may be extremely difficult for you to work.

And the dedicated space for electrical equipment, extending from the structural ceiling from the floor which is equal to depth and width

Also, panels are meant to be readily and easily accessible, which means that the space should not be utilized as a storage space, be situated over the means of a stairway or that a ladder would be needed to get to it. They can also not be installed in areas such as clothes closets or places where there are materials that could be easily ignited. And to also avoid corrosion problems, they cannot be installed in areas of high moisture such as bathrooms.

Code requirements which are specific to your area could be gotten from your local electrical inspector.

HIGH-TEMPERATURE SWITCH ON A FURNACE.

A very significant device used in forced-air furnaces is the high-temperature limit switch which is also called limit switch or just limit switch. They are powered by gas or heating oil. At appropriate times, this limit switch gets the blower fan to go on and off after sensing the temperature of the furnace. In cases of very high temperature in the furnace burners, it shuts it down.

Recognizing a Limit Switch

Typical of a limit switch is a long temperature sensor probe which is connected to a mounting plate.  The probe reaches through the furnace housing wall, and the plate fastens to the furnace exterior. Typically, the mounting plate includes two or more terminals that accept control wires for the blower fan and the gas valve for the furnace. The location of the switch varies with the furnace type, but is usually located in the plenum of hot air supply, above the furnace’s combustion chamber or heat exchanger.

Function of the Limit Switch

In every typical furnace process the limit switch plays an important role. The furnace burners fire and continue heating the heat exchanger when the thermostat calls for heat. At first, the air above the heat exchanger — in the plenum of supply— is not warm enough to blast into the room, so the limit switch holds the blower off. When the air in the plenum hits the high-limit level on the limit switch, the switch switches on and triggers the blower fan, pumping air via the heat exchanger on its way to the house while concurrently drawing cool air from the house through the air returns and then into the furnace.

The burners shut off when the house temperature reaches the specified value on the thermostat but the limit switch leaves the blower working for a while to draw as much power from the heat exchanger as necessary. Once the air in the supply plenum falls on the limit switch to the lower setting, the switch shuts off the fan right until the next cycle starts.

The other essential limit switch feature is to turn the burners off if the heat exchanger gets really hot— a state that can break the piping in the exchanger, completely ruining the furnace. Overheating may occur if the blower fan is having a problem or the furnace filter is so filthy that this really restricts airflow through both the furnace and exchanger such that the exchanger does not cool as it should.

Malfunctions

A blower fan that does not turn off is a common symptom of a limit switch that is malfunctioning. It occurs when the turn actually doesn’t shut the fan off after the burners have finished and the air exchanger is cold enough.

A wrong connection can also prohibit operation of a furnace at all. If the key has failed completely and is trapped in the open connection, or OFF, position, then the furnace will not work. Repeated overheating can produce the same effect. If a limit switch (which is doing its job) approaches its top limit and will have to shut down the burner four or thereabouts times, the furnace’s control device may go into a “fast shutdown” mode so the furnace will not turn on until the machine is serviced.

Replacements

A furnace repair specialist usually handles a bad limit switch, but it can be done by a DIYer with some basic knowledge of electrical issues and also who knows how to use a multimeter. The fix includes ensuring the continuity of the switch. If the multimeter indicates that the resistance is constant, this implies that the switch is bad; removal is basically a matter of unscrewing the switch plate and then adding an acceptable replacement.

ALL YOU NEED TO KNOW ABOUT HYDRAULIC-MAGNETIC CIRCUIT BREAKERS

Hydraulic-magnetic breakers secure circuits after a time delay by cutting power.

As a tripping device, they are not dependent on temperature, so they sometimes see use where there are high ambient temperatures. The insensitivity of these breakers to temperature often allows them as candidates to protect low-current circuits, as it is with sensitive coils, which even in the case of a short one would not produce much heat. For similar reasons, when a fault has cleared, they do not need to cool down before they can restart.

Traditional hydraulic-magnetic breakers consist mainly of a solenoid and an armature which connects to a collection of contacts through a linkage assembly. The charging current is connected so that it passes through the solenoid coil. The spring-charged plunger (or core) of the solenoid travels back and forth in a hermetically sealed tube which is filled with silicone damping fluid.

Currents below the circuit breaker rating do not generate sufficient magnetic flux to overcome the spring’s force to the core. But overloading currents make the core travel to and ultimately reach the pole piece. Once these two parts are in contact, the magnetic circuit’s reluctance drops significantly. This draws the armature with enough force to break the mechanism of the latch and trip the breaker to the pole face. The action isolates the contacts and disrupts the current flow through the solenoid coil, thus allowing the core spring back to its position of rest.

Silicone fluid controls the speed at which the core travels. The damping produces a regulated pause in time prior to breaker trips. The waiting time is inversely proportional to current magnitude. The time delay is useful as part of their normal procedure for having loads draw short-duration overcurrents. A typical example is the one in a motor which is starting up.

In a situation where there is a short circuit, the process is quite different. The magnetic flux created by the coil here is sufficient to draw the armature to the face of the pole and to trip the breaker even as the core has not moved. This action takes place within the immediate trip area of the circuit breaker.

Such breakers can be used up to 10 kA at 125 and 240 Vac in a broad range of sizes including current ratings up to 100 A and short-circuit interference capacities. Conversely, for systems controlling sensitive equipment, trip points can be as small as 20 mA.

Human Body Applications for Pressure Mapping Technology

A quantifiable measure of human experience is vital to the development of consumer products or human health and safety equipment.

A quantifiable indicator of human experience is important for the design of distinct designs when it comes to designing human health and protection devices, or consumer products. Pressure mapping technology could be of use for design engineers to examine how a human subject communicates with an object or system, how a wearable tool suits and supports the subject, and other important aspects that other approaches may not be able to reach. To know how pressure mapping could be used in several consumer goods and health & safety projects, access this eBook.

Shop for magnetic circuit breakers here.

THE REQUIREMENTS FOR A CIRCUIT BREAKER PANEL BOX

Reviewing the National Electric Code (NEC) often comes whenever there’s a need to start electrical works. Explanations on the many requirements and rules are presented in this codebook while at the same time providing safety guidelines. There’s a very strong need to conform to the NEC code when choosing a location for a new breaker panel or even a replacement.

Some basics for how our breaker panels are affected by electric codes will be discussed here. And this will cover situations of new construction and also the replacement of panels. For when you are adding circuits, getting your circuit breakers rearranged or even adding a sub-panel, make sure you employ the services of an electrician so as to get a job rightly done. This way, you’ll be sure to have met the electrical inspection requirement while also ticking the very important box of safety too.

Getting the right location and clearance

As a matter of fact, the decision on the placement of the breaker panel has to be the first important point to consider. Above all, it must be placed in a safe and easily accessible location. In other words, the location can’t be an overcrowded place. Expected right in its front is a clearance of at least 3 feet. Also expected is a weatherproofed box for a situation when we have any plumbing close to the place.

Here are a few more details:

The least height off the ground required for placement of a breaker panel is 4 feet and also not higher than 6 feet

A working space of at least 30 inches in width and from the ground up, 72 inches.

These clearances should be rid of large objects of any sort such as furniture for easy accessibility.

Circuit Labelling

It’s a matter of must for circuit breakers to be labeled. If your circuit breakers happen not to be marked or that power does not turn off when you flip a breaker, you certainly need to talk to an electrician so as to figure out what could be wrong.

Life gets easier for you and even your electrician when your breaker panel is labeled. Labeling breaker panels also makes things easy for first responders in times of emergency. There may be a need for emergency personnel such as firefighters to shut off power during emergencies and having labeled breakers will very much give them less stress.

Grounding and Neutral Terminals

For appropriate breaker panel safety, the NEC makes available several safety codes by defining the appropriate installation and connection guides for grounding and neutral terminals. For example, you can only attach just one neutral conductor to each neutral terminal. The breaker panel’s metal cabinet has to be connected to a grounding conductor.

 There are lots of explicit codes for methods for wires connection and cables to terminals, conductors types used and safe arrangement. In short, all cables and wires must be connected safely.

You Can Always Talk to an Electrician Whenever You Are in Doubt

Professionals can always explain the rules to you. For instance, a situation when you are thinking if you can place your breaker panel in your closet. Of course, you can, so long as the closet is not in or very much close to a bathroom. Nonetheless, the working clearance which is expected to be around the panel must be in place. In other words, a very much appropriate closet will be a large one with adequate empty space

ALL YOU NEED TO KNOW ABOUT THE HEAVY DUTY LIMIT SWITCH

A competitor gave the description for their watertight limit switch as thus: “…have internal parts that are protected against splashing or hose-directed water seepage within the limits of the NEMA specified tests for type 4 watertight enclosures. These switches are not sleet or ice-proof.”

Literally they’re saying, “It’s not actually waterproof”.

For engineers who are searching for a compact size, very waterproof and can’t-kill-it – with-a-hammer limit switch we have, well … our entire product range. To break it down, let’s take a look at the major types of switches we make and switch configurations.

For a truly waterproof, can’t-kill-it-with-a-hammer and small sized limit switch, we have all you need with all we have in our product line. For a better understanding, let’s go through foremost types of switches we manufacture, with switch configurations.

 E1 Series Limit Switches

If you take one of our temporary or retained contact pendant sealed Santoprene or Neoprene (extended temperature range) switches and combine them with ***’s unique actuators and bracket mounting solutions, the outcome is a large line of durable limit switches that can be conveniently customized for your specific applications, usually with a purchase off the shelf from one of our distributors. Various combinations of travel variables, electrical configurations roller lever or panel mount setups as well as our standard high-endurance features are sold as standard products.

Ball and Plunger Limit Switches

The J4 series limit switches: We have this in both the ball and plunger variation. These have gotten great acceptance for use in submarines, emergency and work trucks, construction vehicles and even military vehicles. You can activate these switches mechanically by the opening up of a valve and letting it reach the limit of its travel, or transmission sliding into neutral, or the closing of a door or hood or any of the several available applications where durability and size were the main concerns.

Built of all stainless steel with a proprietary double locking system, these switches are typically the final resort of engineers who don’t want to play around with safety limit switches that malfunction on the field. That’s because our limit switches configurations have applied to more than one million cycles.

You get to say “Heavy Duty” easily with *** limit switches.

Did we tell you that our limit switches operate at -40F or 220F and they operate perfectly well underwater?

*** limit switches are weatherproof and waterproof.

The Basics of Limit Switches: Beginners’ Course

Introduction

The first thing to note about limit switches is that they are electromechanical devices. This means that they operate on both electrical energy and energy due to motion (mechanical energy). The simplest way to define limit switch is that they are electromechanical switches that carry out specific functions and operate as a particular object moves or is identified.

A mechanism very similar to this is that of the toilet float valve. As the tank fills up with water, the float is raised and it keeps rising until it reaches a level high enough to stop water from entering into the tank.

Application of Limit Switches

There are several ways limit switches can be applied and several functions they can perform. For instance, let’s say you own a truck that evacuates refuse, you want to make sure that each time you load the bed is secure and down before you start driving off. A limit switch can totally help you out here. A position limit switch and a button actuator can be automated such that when the bed has been let down properly, the button is pressed down and this activates an indicator light or sound close to you, letting you know that all is good and you can drive off. A position limit switch as shown below is used for these sorts of operation.

Position Limit Switch

Another way limit switches can be applied is in the automation of doors. Again, let’s assume you have a motored roll-up door and you’d like to automate it such that the motor stops when the door has been totally opened. As in the case above, a position limit switch can be of great help. The adjustable arm of the position switch will be linked to a pivot point which would also be connected to a switch. Once the door is opened up till its full height, the roller of the limit switch is touched and it starts to rotate. Once this happens, a switch is activated and the motor shuts off. In place of the roller, the switch can be activated using a plunger or button. It all depends on your preferences.

Other Types of Limit Switches

Apart from the Position Limit Switch, there are several other limit switches currently in use in modern times. The type of limit switch you use is dependent on the type of task you want to perform or problem you want to solve.

  • Rotary Gear Limit Switch

Oscar Rotary Gear Limit Switch

One more time, we would assume you have a rotational motor and you’d like to automate it to stop working or shut down after rotating for a set number of times. As the shaft on the limit switch turns, the motor turns. This is because the shaft is in contact with the motor through gears or sprockets. The limit switch, itself is made up of some gears and a series of cam. The number of gears inside the switch determines how many times the motor would rotate. As the gears in the switch and the motor turn, they rotate until they achieve the maximum number of turns.  Once this happens, the cam in the limit switch activates an electromechanical switch which turns off the motor.

These sorts of limit switch have several applications such as windmills, wind turbines, boat lifts, etc.

  • Proximity Limit Switch

A proximity limit switch is used to detect and indicate when a little bit of metal is present in an environment or material. It does this using a magnetic field which is able to detect when a disruption, usually due to the presence of a metallic object has occurred.

  • Windmill Limit Switch

The windmill switch is a little more complex and can operate in more than one direction, working with several positions and switches.

Travel Chart of an Activated Windmill Switch

A common application of the windmill switch is seen in gantry and bridge cranes, as shown in the image below. As seen, the crane can move to and fro (or front and back) over the length of the beam overhead. As it moves across the beam, a position limit switch can be used to determine and indicate its relative position.

Image of a Gantry Crane

  • Reed Limit Switch

A reed limit switch is used to indicate the presence of a magnetic field, and in some cases, determine how close it is to a magnet.

As you’ve already discovered, limit switches perform a wide range of functions and have varying sizes, modes of operation and applications. Hopefully, this piece has been very useful in helping you understand them better.

HOW TO UNDERSTAND THE MAIN CIRCUIT BREAKER IN YOUR HOME

Without adequate knowledge of the main circuit breaker, you may find it difficult to perform electrical repairs in your house. The distribution of electric current to every part of the house is done from the main circuit breaker. It is the link between the utility company and your house.

The role of the utility company is to make sure electricity reaches your house. They do this through a service drop electrical line. There is always power in the service drop. If power does not get to your house, it could be because your circuit breaker has halted the passage of power.

In this article, we will be explaining everything about the main circuit breaker in your house. We will also be opening your eye to the major dichotomy between a main breaker and a branch breaker. We are only educating you. If there is a technical difficulty, reach out to an electrician.

What every beginner should know about a circuit breaker

The main circuit breaker in any house is usually located in the electric service panel box. In some old residential structures, the service panel is usually mounted to the wall. It is very similar to a metal cabinet and opening it for the first time is usually a big deal. The inner compartment of the main circuit breaker houses so many circuit breaker switches arranged in rows.

In some cases, these switches are numbered and labeled. These numbered or labeled breakers are called the branch circuit breakers. Every branch breaker is responsible for a particular portion of the house whether it is the living room, or kitchen.

A little bit above the branch circuit breaker is a large switch. The size of this switch is usually larger when compared to the branch switches. This large switch is the main circuit breaker and it is responsible for controlling the amount of electrical energy that the branch breaker receives.

When the main circuit breaker is switched off, the flow of power to the circuit breaker panel will seize.

What is a circuit breaker?

The circuit breaker is a defense system created for all circuits and appliances in a household.  Anytime there is excess current or overload, the circuit breaker prevents it from getting into any of the circuits. The circuit breaker is a switch whose source is the circuit board. It only acts if it senses an abnormal flow of current.

Before the advent of a circuit breaker, fuses were used to protect appliances. However, circuit breakers are well configured to prevent a short circuit from wrecking havoc to the gadgets and appliances in a home.

The problem with a fuse is that it had to be replaced frequently as a result of a blown filament. The circuit breaker is quite different in the way it operates. When a power surge occurs, you only need to reset the breaker and its operation will be fully restored. There are different types of circuit breakers. The low voltage circuit breaker is used in places of residence. On the other hand, the high voltage circuit breakers are used for industrial and commercial purposes.  The third categories of circuit breakers are the medium voltage circuit breakers.

How does a circuit breaker work?

Although all circuit breakers perform the same function, there is a difference in their method of operation. The class of voltage and maximum permissible current are some of the other factors that affect the operating principle of a circuit breaker.

A breaker should be able to spot and arrest abnormal current conditions before damage is done to any of the household appliances.

The low-voltage circuit breakers are the most basic of all circuit breaker types. As earlier explained, they are used in places of residence. Although all circuit breakers do the job of preventing a short circuit or over-current from damaging things, the branch circuit breaker and the main circuit breaker are not the same.

How is a branch breaker different from a main breaker?

Although very similar, these two breaker types have some differences. Their functionality and operating principle is basically the same. However, the main breakers have a bigger size. The branch breaker can only handle smaller current values.

The main breaker connects to the two power lines that are responsible for conveying electricity into the house from the utility company. On the other hand, the branch circuit breakers are attached to the hot bus bars which are slightly below the main breaker.  The flow of electric power to the hot bus bars is orchestrated by the main circuit breaker. When the main circuit breaker is shut off, there would be no power in the whole house.

WHY A CIRCUIT BREAKER OR FUSE MAY BLOW

A typical electrical system is made up of different circuits and electric outlets. These circuits are shielded by a fuse or circuit breaker. Without a circuit breaker, it would not be possible to control and protect circuits and appliances. However, there are a few old houses that do not have a circuit breaker. These houses make use of a fuse for circuit control.

Usually, circuit breakers have switches for turning on and putting off the device. Apart from that, they are mostly located in a main service panel.

Most times, when the lights go off in a residential apartment, it may be because of the action or inaction of the circuit breaker. It could also be caused by a faulty fuse. This is because a fuse and breaker are configured to put a stop to power flow if a problem arises. A circuit breaker can be reset or reconfigured. On the other hand, a fuse needs to be replaced when it becomes faulty. A burnt fuse is usually characterized by a burnt metal filament.

To avoid having to replace fuses and resetting circuit breakers often, you should have an idea of the root cause. It could be because the fuse or breaker is performing its primary duty of circuit protection.

It could also be because of damage or fault in the circuit breaker. A fuse or breaker will trip off when any of the following things occur.

An overload

This is the primary cause of a tripping circuit breaker. It implies that one of the circuits is trying to exceed its maximum load bearing capacity. When too many gadgets operate simultaneously, the circuit breaker will trip if its internal sensor is still intact. This tripping will discontinue the flow of current to such a circuit. Hence, it will no longer be active. To reinitiate the circuit the breaker needs to be reset and this is a very simple thing to do. All that is needed is for the switch to be pushed to the ON position.  When your breaker trips frequently, it could be an indication that the circuits are been overworked. Hence, load shedding needs to be done so that one circuit does not handle more current than it can ordinarily take. It could also be because the circuits in your house are inadequate. Therefore, more circuits need to be installed.

Short Circuit

This is another common cause of a tripping circuit breaker. It could happen when two wires that should not come in contact touch each other. It could also be caused by issues surrounding wiring of a gadget or appliance. It is not easy to trace or keep track of the cause of a short circuit. Therefore, calling on an experienced electrician is the best thing to do.

Also, if you notice that your circuit breaker trips almost immediately after a reset have been done, it could be because of a short circuit.

Ground Fault

This is another form of short circuit. This one occurs when a hot cable or conductor makes physical contact with a ground wire. It is important to keep the environment dry and free from moisture because when a ground fault occurs, there is a high risk of electrocution.

It is not enough to fix a ground fault, it is better to prevent them from occurring. A ground fault is characterized by a drop in resistance and an increase in the rate of flow of electric charges. It has so many of the features of a usual short circuit.

Arc Fault

Arc Fault Circuit Interrupters were produced to cushion the effects of arc faults. These breakers are powerful enough to sense irregularity in power supply between two nodes or contact points in an electrical system. Apart from that, when an overload occurs the AFCI trips automatically. The AFCI is also able to guide against a ground-fault and short-circuit.

An AFCI can be reset in a similar way to a normal circuit breaker. However, when tripping is too frequent, it could be because a wire connection is not tight enough. Hence, arcing will happen severally.