EV Charger Throttled-Current Schedule (NEC 625.42)
What each car actually gets when the EVEMS throttles, the operating side of ev-load-management-ems: throttled = min(charger_max, aggregate_limit / active_chargers). Four 40 A chargers on a 100 A EVEMS budget do not each get 40 A - the system throttles all four to 25 A, and only two could run at full rate at once. Drop to two active and both get their full 40 A. Predicts charge times and explains why the last car in slows the rest. A planning aid, not the EVEMS configuration.
Formula and source
throttled_a = min(charger_max_a, aggregate_limit_a / active_chargers); full_rate_count = floor(aggregate_limit_a / charger_max_a); all_full = active_chargers x charger_max_a <= aggregate_limit_a.
NEC 2023 (NFPA 70). Article 625 (625.42(A) energy management systems) per-charger current sharing.
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