All right, time to peel back the veil of mystery of an arc flash study a bit.
No, there are NO blood sacrifices, Ouija boards, or magic eight balls involved in determining the cost of an arc flash study. There are, however, many factors that do play a role in determining the cost. These factors include things such as the size and type of facility, amount of electrical equipment, accessibility of equipment, and complexity of the system. The thing that all of these items have in common is that they determine the amount of time the engineer will have to spend on a project doing the data gathering, modeling, and labeling.
The first step to starting an arc flash study is performing the data gathering. Once on site, the engineer will start working his or her way through the electrical system doing things such as tracking down equipment, obtaining protective device data and settings, cable information, transformer nameplate data, motor data, and generator nameplate data. This is where having up-to-date drawings can have a big effect on a project’s cost. Accurate drawings can drastically affect the amount of time on site required to track down equipment or determine where each is fed from.
The job for the engineer is not over when he or she leaves the facility. Next, the engineer enters the data collected during the walk-through of the facility in the modeling software. When entering the data, the engineer creates a model of the system that is represented as a oneline drawing. It is during this time that the engineer will also be entering protective device information, transformer data, and setting up scenarios for running the arc flash study. Once all of this has been done and scenarios run, the engineer will review the results and make note of any discrepancies. This usually leads to multiple iterations before the final product is achieved. The study can be further complicated by the complexity of a system.
The final part of the process takes place when the engineer visits the site to apply labels. During this phase, the engineer will walk the site and place arc flash labels on all evaluated equipment. At the conclusion of the trip, the engineer will usually have a closeout meeting with the client, at which time the findings of the report will be discussed and hard copies of the report handed over.
This project involved a large food processing plant with its own 115KV substation and medium voltage distribution loop that fed 12 padmount transformers. From there it was distributed out through 480V switchboards to a multitude of MCC’s and panelboards. This original part of the facility had been in place for approximately 60-80 years, with multiple expansion projects taking place in between then and now. The facility personnel had decent, if outdated, drawings with hand written notes on them. With some help from facilities personnel, data gathering on this project ended up taking about fifteen days. Following the site visit, about five weeks was spent building and running the model. Labeling the equipment took seven days on site. This project ended up costing approximately $70K.
This project involved a small multi-family housing development where an electrical contractor was performing a renovation. The system was comprised of one 208V, 800A panelboard that fed to two metering boards, and a few small house panels. For this project the electrical contractor provided all the required field data and documentation for the new equipment. The contractor also applied the arc flash labels. As this was a small system, with the majority of hours coming from modeling, the total hours ended up coming to just under two eight-hour work days. The total cost was just under $3,000.
If the figures above look intimidating, be assured that companies can do a lot to help reduce the cost of an arc flash study. Those facilities that have the following in place will have the most efficient, cost-effective study:
Maybe the dollar amount looks steep to you now – a natural reaction from most clients at first. Consider then the potential cost of lack of knowledge – what you do not know can hurt you or those around you. Electrical workers who do not know the hazards in their work area or what steps to take to mitigate the hazards can very well end up getting hurt. Once a shock or arc flash incident occurs, different costs accrue.
The numbers show that knowledge and implementation of that knowledge can cut costs drastically when compared to the cost of an electrical injury or electrocution (death) at the workplace. The cost of worker’s comp and possible ligation, along with company costs of damaged equipment and time lost from work, can add up to many times more than the costs of an arc flash study and subsequent training and audits.
Employers are required to provide a place of work that is free from hazards that can cause death or serious harm to workers. A key step to meeting this goal is to know the electrical hazards involved – which only an arc flash study can provide.
There’s no need to make a hasty decision. But make sure to find out the answers to your questions about the importance of having a current and accurate arc flash study at your facility.
The professionals at e-Hazard are happy to answer those questions! Contact us on the web at mailto:firstname.lastname@example.org or call us at (502)716-7073.