AMTEC Integrated Manufacturing System Simulator (AIMSS) Example

It is important to understand the equipment that is being serviced. Using electrical drawings and knowledge of system components is critical to identifying possible arc flash hazard points. The power coming into the electrically energized equipment may come from the plant or directly from the utility power distribution system. Where the utility system and the equipment connect is referred to as the service point. The electrical system which enters the disconnect is "upstream", known as the line side. The power exiting the service point after the disconnect is considered the load side, "downstream" of this point, and is where applicable NFPA and NEC regulations are to be followed by the equipment owner. Power may be still live inside cabinet when locked out at the line side of the disconnect unless power was disabled further upstream. Note that an employee working on the utility side of the service point is required by OSHA to follow its General Industry safety standards which recognizes the NFPA 70E standards.

Many components within an electrical cabinet or panel may have one level of line voltage coming into it and another level exiting, with the line side incident energy being normally higher than the load side incident energy. Use the AMTEC Integrated Manufacturing Systems Simulator (AIMSS) (Figure 1) as an example to identify potential sources of arc flash components in the electrical cabinet.

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Figure 1: AIMSS Electrical Panel

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