CEC Rule 8-104 (80% continuous rating)
Overloaded Circuit Checker
Add up everything plugged into one circuit and check it against the circuit's safe continuous rating.
1. Circuit & Devices
2. Circuit Load
80% continuous ruleTOTAL CONNECTED LOAD
0 W
SAFE CONTINUOUS LIMIT (80%)
— W
Result:
Add your devices to check the circuit.
Why 80%, not 100%
- A circuit's breaker rating is its absolute maximum, not its safe running target — the CEC treats continuous loads as safely sustainable only up to 80% of the breaker rating.
- For a 15A circuit, that's 12A (1440W at 120V); for a 20A circuit, that's 16A (1920W).
- Running consistently near or above this 80% mark causes heat buildup over time, even if the breaker doesn't trip immediately.
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