Why Arc Fault Calculations Are Inevitable?

Electrical Safety and Power Quality

It is important to identify the Available Fault Current or AFC when choosing various protection devices. It is not only necessary for the purpose of safety of the entire system and the building but it is also a mandatory requirement mentioned in the Chicago Building Code and in the NEC.

are here to provide you with the best arc fault current calculation services to meet different requirements. Whether you own a commercial, residential or industrial facility, our engineers will take care of all the issues associated with arc faults. We will not only calculate different readings but also provide you with an array of solutions.

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How Does The Arc Fault Occur And What Are The Main Causes?

In the case of a short circuit, the resistance is very small and for this reason, the current becomes excessively large. The calculated current will go to infinity if the resistance is zero. But zero resistance is not possible because high conducting wires such as copper wires also have some resistance to offer. For this reason, it is important to identify the total amount of resistance within the network from the power source to the fault location.

There are different causes of fault currents and these include:

  • Lightning strikes
  • Dirt and debris
  • Equipment failure
  • Environmental conditions
  • Corrosion
  • Human error
  • And dropped tools

Do You Need A Partial Modification Or A Full Revamp To The Network?

Our technical staff can easily compare the maximum AFC with SCCR or Short Circuit Current Rating. NYE recommend that each time your facility features a change in equipment or installation of a new one then you should redo all the fault calculations again. The redoing of all the fault calculations is also mentioned in the Chicago Building Code as well as the NEC.

When any modifications to all the electrical equipment are done it can result in alteration of the overall AFC available for service. Therefore, it is important to do the recalculations to ensure the ratings of the service equipment for the AFC available. Consequently, the field marking will also change as per the new level of maximum AFC for the service.

NYE Calculates Both Bolted Faults & Arc Faults

There is another type of fault as well which is known as the bolted faults. Bolt faults have solid connections and it enables the current to flow through the conductor. The bolted fault will occur when the installer links the source of power to the ground rather than to its appropriate position. The protective device will immediately trip when the power is turned on to create the bolted fault. Due to the protective device, the damage is kept in check and typically limited but this fault can also create the highest level of faults too.

On the other hand, an arc fault is different because it doesn’t involve a solid connection but the conductors are close enough for the current to jump over the gap and create an arc. This initial arc can ionize the air and create a plasma that enables the flow of current to be rapidly fast and remain sustained. This result in arc blast or arc flashes. In the case of an arc flash fault, current recalculations are necessary. These estimations determine the safe boundaries as well as the needed PPE and other field markings.

Types Of Arc Faults We Deal

Our technical engineers understand different types of arc faults. It’s an unintended or abnormal link of various live elements. The connection can be either to earth or with other elements. Such connections have very low impedance and for this reason, the flow of current through them is large. The amount of energy that is present within these fault currents can heat up different components very fast. Now, this heat energy can generate highly excessive forces and can be a cause of devastating explosions.

Here are major types of faults:

  • 3-phase faults
  • Earth Faults
  • open-circuit fault
  • Phase-to-phase faults

The highest amount of fault current goes through 3-phase faults but there are some exceptional cases as well where earth faults and phase-to-phase faults give more currents.

3-phase faults : In this fault, all the phases are shorted together which means that L1, L2, and L3 are linked. Finding the fault current within the network at any point is done by summing all the impedances within the entire electrical system from the source to supply and this summation also includes the source along with the point where the fault has taken place.

Although symmetrical faults are considered as the most severe due to large fault currents, the single-phase to ground faults are the frequents one that occurs. If you don’t take the single-phase fault properly it may grow to a symmetrical fault which is most severe.

Earth Faults : In this fault, one of the phases is directly linked with earth. For instance, any one of the phases including L1, L2 or L3 is directly earthed. For the purpose of finding the fault in the network at a given point, all earthed impedances are summed within the network in between the supply source and the impedance of the return path. This sum also includes source impedance.

Open-circuit fault : There is a fourth type of fault as well and it is known as the open-circuit fault. However, this fault doesn’t create a short circuit. This fault is initiated by the current that is interrupted unintentionally. Therefore, it is absolutely necessary to install the protective system so that they can prevent any damages to the equipment and also save people from any harm in all the above-mentioned situations.

Phase-to-phase faults : These faults have two phases connected with each other for instance L1 is linked with L2. Like the previous case, the fault current is the voltage (nominal applied) divided by total impedance.

Our engineers can assess all these fault types quickly and come up with a solution after going through all the calculations. We at NY Engineers understand how all these phases work and our staff has plenty of experience when it comes to handling different faults and calculating their arc currents.

NYE Arc Fault Current Calculation Services

Customized Services

Electrical Safety and Power Quality

NYE calculates accurate Arc fault to protect your building from high power discharge of electricity. We check all the system to eliminate the possible threat and recommend the Arc Fault Circuit Interrupter according to the nature of the fault.

Our technical staff has one aim in their mind and that is to make your facility as safe as possible. NYE is the leading service provider of a different arc fault current calculations in the city of Chicago. Our technical staff understands the issue and provide you with a solution that is customized according to the needs and requirements of your building.

It is of utmost importance that MEP Engineers ensure that the systems installed in your facility are safe from any hazardous both in the short and long run. If you are not sure of the current MEP systems of your facility then you can hire our services for this purpose. We at make sure that your facility meets all the requirements set by the Chicago Building Code.

The best part is that our technical staff provides you with customized services and yet they are cost effective. While recommending you with an array of solutions for your arc fault problems our engineers will keep a sharp lookout on the cost aspect as well. Therefore, you will get high-quality services that are tailored according to your facility’s specific needs at nominal charges. There is nothing better in this world than tailored services at nominal rates.

All service equipment excluding the dwelling units has to be marked legibly with maximum AFC. The markings must include the date of the calculation of fault current and the sufficient durability of the environment in which it should be performed.

Identification Process Of All Current Sources At NYE

Electrical Services

We at NY Engineers understand how all these arc faults occur and how to work them out. Prior to any calculations of fault current, our technical engineers will identify the source current.

This consideration can also include any and all sources that have not been considered previously. Short circuit fault currents have four possible sources.

  • Onsite electrical generators are one of the sources of short circuit faults. These are very close and fault current is limited by electric current and generator impedance.
  • The synchronous motors are another source because it is an AC motor. Its speed is directly proportional to electric power frequency. When power fails in the case of a short circuit, the motor will continue to rotate due to the mechanical load’s inertia. Therefore, this motor will act like a generator that is supplying the current and this will add to the total amount of current that is flowing through the fault.
  • Induction motors will also act like synchronous motors and will start playing the role of a generator if a short circuit occurs anywhere within the electrical system. But in this scenario, the fault current will only last for a few cycles.
  • Utility systems can also create short circuits because most of the current comes from them. The short circuit level will rely be based upon:
  • Generators’ impedance
  • Rating of secondary voltage from transformer and impedance
  • Circuit’s impedance from the transformer to short.

Our technical engineers will perform a short circuit study for the purpose of calculation of the arc fault current. The worst case scenario in this situation is looking for the bolted arcs in 3-phase electrical systems.

NYE Offer Arc Fault Calculations For Your Entire Facility

Once our technical professionals are done with the calculations and estimations labeling is done for the entire system. However, it is important that these labels should be clearly visible and approachable. This is necessary because each time when the recalculation is done the printing will feature new labeling.

It is of utmost importance that you should go for arc fault calculations of your entire facility. It will make sure that your entire electrical system runs smoothly and it can also remain safe for the electrical workers and the occupants of the facility.

Apart from the safety reasons, it is also a mandatory requirement that every facility owner whether residential or commercial, must go through. The Chicago Building Code along with the National Building Code provides with all the details on how to conduct arc fault current calculations and what measures are needed to be taken for this purpose.

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