Item 17 - Arc Flash Analysis and Safety Program Development

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study and IEEE standard requirements. As necessary, the cover of the equipment such as panelboards, switchboards, motor control centers, switchgears, etc. shall be removed in order to capture the required information. All the documentations including the existing drawings shall be reviewed before and after the field data collection to make sure the required information have been obtained and if additional information can be retrieved to be incorporated into the models. To gather the information and properly capture the required information the help of the City of Santa Ana staff and electricians are required and shall be coordinated in advance. 4.2.Device Evaluation Study The prepared models will be used to calculate the worst case scenario fault currents which is the maximum fault currents produced by balanced three-phase and unbalanced faults at each fault location. All the scenarios will be presented in the report in a tabular format with notes for ease of identifying the cases. Low voltage and medium voltage equipment will be presented in separate tables identifying the device evaluation results in a color coded format for the failed equipment against their short circuit withstand capabilities along with the practical notes to address the issues or possible summarized solution(s). Equipment with Marginal device evaluation condition also will be identified for considerations. All the identified problems, solutions and recommendations including possible replacement of the existing equipment, upgrading the equipment to the higher SCCR rating, addition of current limiting devices or device series rating recommendations based on the approved and published manufacturer's tested tables will be mentioned in the executive summary section of the report. 4.3. Coordination Stud The protective device coordination study determines overcurrent protective relay and circuit breaker settings in order to provide an optimal compromise between protection and selectivity where possible and/or practical. In order to properly study the protection and coordination of the power system models, all the protective device settings including the adjustable and fixed devices shall be incorporated into the model. Subsequently, time characteristic curves (TCCs) will be created per following: o Individual TCCs will be created for each device's zone of protection. For example for a typical switchboard, the upstream, main and downstream protective devices will be included in a TCC to show the selectivity and coordination of the devices.