Item 17 - Arc Flash Analysis and Safety Program Development

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Each substation was successfully energized and commissioned and all tests were passed according to the power system study report for this project. Project-3: Los Angeles Metropolitan Transportation Authority — Los Angeles, CA Year Completed. 2021 Client Name: LOS ANGELES METROPOLITAN TRANSPORTATION AUTHORITY Contact: Teo Dominguez Phone: (818) 763-9179 The scope of this project was to model three entire stations of the "Los Angeles Metropolitan Transportation Authority" (East/West 1st Central Stations, East/West 2nd Broadway Stations and East/West 2nd Hope Stations) with a lot of upgrades to the existing equipment, new installations of breakers and relays, and extending the power distribution to the new circuits. The analysis included coordinating with the upstream 34.5kV circuits with normal/reserved power from the utility and two feeds for each station. Each station has very large motors and a bunch of smaller motors with UPSs. The new installations as well as replacements/upgrades/retrofits to the exiting breakers needed to be evaluated for the available fault currents from the utility. In addition, the entire stations for all three needed to be re-evaluated for the coordination study, and new and recommended settings had to be provided. Arc flash study needed to be performed for all three stations as well. During the short circuit study, a few breakers/MCCs failed. Looking further into the study and verifying the actual operation of some of the larger motors, we found out some of them operated intermittently and not at the same time. That alleviated the problem of high fault currents contributing from those larger motors. We also came across situations that by adjusting and recommending settings for some of the breakers to achieve proper coordination and selectivity, the incident energies on some of the equipment would go higher. We also suggested the replacement of the breakers with more advanced electronic trip devices to mitigate the incident energies. However, due to the associated cost, the owner decided to stay with the current equipment. The owner of the project also decided to utilize the recommended settings for some of the non -critical circuits, which could be de -energized for performing work on them. For the rest, the old settings were utilized to keep the incident energies down while compromising selectivity since those circuits could not be de -energized prior to work since they were part of the critical circuits and had to be kept energized at all times. 7. Electrical Safety Program SMAART POWER will create and implement a Safety Program which will be in accordance with the guidelines set out by OSHA and the 70E requirements for electrical safety in the workplace, based on the specific needs of the Santa Ana Public Works Agency. The Safety Program will include, but not be limited to the following: - Defining the requirements to meet safety standards