![]() ![]() Based on the DC Polarization/Depolarization Current Measurement principle, it’s a non-destructive method that applies a maximum of 30% of the cable’s voltage rating. This unique, on-site diagnostic service determines the health of XLPE cables while preserving their integrity. We have partnered with National Research Council Canada (NRC), the Government of Canada’s premier research and technology organization, to diagnose the health of XLPE cables without damaging them. Inside this boundary, accidental movement can put a part of the body or conductive tools in contact with live parts.Įnergy Ottawa offers a state-of-the-art, non-destructive cable measurement system for the dependable assessment of medium voltage distribution cables. Only qualified persons may cross into the restricted approach boundary. Unqualified worker can only cross this boundary if he or she is continuously escorted by a qualified worker. ![]() The limited approach boundary is designed to keep unqualified workers safe from shock hazards. Workers must select gloves that have a rating for the level of voltage to which the gloves will be exposed. Workers must be protected from shock by wearing rubber insulating gloves if their hands enter the restricted approach boundary. Many electrical workers have been injured because they used test equipment rated for 1,000 volts on circuits energized at 4,160 volts or higher. Nominal voltage is a value assigned for conveniently designating a voltage class, such as 120/208V, 277/480V. IEEE 1584 a guide commonly used for performing arc flash incident energy and boundary calculations, defines the working distance as “the dimension between the possible arc point and the head and body of the worker positioned in place to perform the assigned task.” The working distance is the distance at which the incident energy is calculated. The amount of current supplied by the electrical equipment’s upstream device.Ī recommended list of shock and arc flash hazard PPE that shall be worn when performing safe work on equipment that is not placed in an electrically safe condition. If a person were standing at this distance from the arc source, they could receive a second-degree burn. The Arc flash boundary is the distance from a possible arc source to where the incident energy drops to 1.2 calories per square centimeter. This energy is measured in calories per centimeter squared. Personal Protective Equipment (PPE) clothing requirements are specified from a clothing library.Incident energy, as indicated on the arc flash label, is the level of thermal energy that one would feel at the working distance in the event of an arc flash. Incident energies and arc flash boundaries are calculated using the NFPA 70E standard. The duration of the arc is determined from the time-current characteristics of the applicable device and the calculated arc fault current. Trip times are automatically calculated from the protective devices settings, the library of protective device information, and arcing fault values. It calculates the incident energy and arc flash boundary for each bus location included in the power system. Preparation of arc flash equipment labelsĪRCAD offers Arc Flash Analytic software for arc flash evaluation and labeling.Recommended personal protective equipment.Calculation of arc flash incident energy.Calculation of arc flash boundary distances.The requirements of the NFPA 70E include the following items in the arc flash hazard analysis: The arc flash hazard calculations are based on the calculated values of fault currents and the clearing times of over-current protection devices found in the short circuit study.
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