Theater Calculators
Ohm’s Law AV Rack Load Calculator
https://www.theatersizing.com/calculators/ohms-law-rack-load/
Estimate only — not a calibrated SPL meter, an acoustic report or an electrical design. Confirm with measurement.
Ohm’s Law AV Rack Load Calculator
I = P / V. US 120 V and EU 230 V change the amps a lot. Continuous AV loads should stay under 80% of the breaker.
Inputs
Results
- Current
- 2.57A
- Breaker load
- 16.0%
- Within 80% rule?
- Yes
Calculation method
Amps = watts / volts. Percent of breaker = amps / breaker × 100. Fits if ≤ 80%.
Exact formula
I = P/V. OK if I ≤ 0.8 I_break. Limits: resistive-ish PF, one circuit, no motor start, no 208 V three-phase.
Frequently asked questions
Why 80%?
US continuous-load guidance. Many EU installs treat 16 A similarly for long cinema nights.
120 V vs 230 V?
Same watts, half the amps at 230 V. A US 15 A circuit fills up fast.
Two circuits?
Split display vs audio if the sum fails. Do not share with kitchen loads.
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