Existing Load from Demand Data
NEC 220.87: turn a recorded peak demand into an allowable calculated load and see how much service headroom is left.
Result
Calculated load after the addition
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Allowance from recorded demand at 125%
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Remaining headroom
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Service capacity
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Service loaded to
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Formula
Calculation logicWhat to check
- Utility interval data or a 30-day recording with the right demand window
- Whether the utility peak actually captures the site peak
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