Originally Posted By: Bob Badger
This post was automatically imported from our archived forum.
To be accurate use the word current in place of voltage.
Think of a faucet turned off, the pressure (voltage) is there, the flow (current) has stopped.
From the NEC definitions.
Continuous Load. A load where the maximum current is expected to continue for 3 hours or more.
Ryan and I may see things differently (isn't the NEC great ![icon_wink.gif](upload://ssT9V5t45yjlgXqiFRXL04eXtqw.gif) ) In my opinion there are very few circuits in a dwelling units that must be treated as continuous loads.
You can say someone may leave a few lights on all day but it is unlikely all the loads on that circuit would be on together for 3 hours or more.
This wording "maximum current" IMO makes it clear, that one or two things on a circuit on all day does not make the whole circuit subject to the continuous load rules.
There are some loads that we always have to treat as continuous, an electric water heater under 120 gallons is one.
A circuit that is considered a continuous load must be wired for 125% of the full load current.
What this means for continuous load dwelling unit circuits is this.
30 amp breaker no more than 24 amps of continuous load
20 amp breaker no more than 16 amps of continuous load
15 amp breaker no more than 12 amps of continuous load
Remember this is for continuous loads, non-continuous loads can load the breaker to 100% of its rating.
Sorry to ramble on so long
Bob (AKA iwire)
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