Sizing the heater CircuitAMPSVOLTSWATTSWIRE dimension COPPERWIRE size ALUMINUMCIRCUIT PROTECTION
121201,440#14/2#12/215 Amp - 1-Pole
161201,920#12/2#10/220 Amp - 1-Pole
122402,880#14/2#12/215 Amp - 2-Pole
162403,840#12/2#10/220 Amp - 2-Pole
242405,760#10/2#8/230 Amp - 2-Pole
322407,680#8/2#6/240 Amp - 2-Pole
4124010,000#6/2#4/260 Amp - 2-Pole
5224012,500#4/2#3/270 Amp - 2-Pole
62.524015,000#2/2#1/0100 Amp - 2-Pole

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The over circuit sizing is based on 75C wire and for reference only. Always consult regional codes for appropriate sizing.According to the National electrical Code heater circuits are considered a consistent load and therefore should be derated by 25%. (For example: a 20 Amp heating circuit can not have an ext than 16 Amps of load connected.)120 Volt heaters call for 1-Pole circuit breakers; 240 Volt heaters require 2-Pole breakers.Use 2-wire cable with ground (Romex™ or BX).When put multiple heaters on a circuit perform not exceed the wattage detailed for the corresponding wire and circuit breaker size. (For example: 2-1000W & 1-1500W, 240V heaters = 3500 watt total. This 3 heaters would call for 12/2 wire and also a 20 Amp 2-Pole breaker if they were to all be placed on the exact same circuit. If an ext heaters are necessary either run a new circuit or increase the wire and breaker dimension to accommodate the load.)A 1500 Watt heater will cost the very same to run whether that is 120 or 240 Volt. 240 Volt heating circuits are an ext common due to the fact that it reduce the Amp attract on her breaker/fuse panel, as the graph shows, you have the right to place more heaters top top a 20 Amp 240 Volt circuit (maximum that 3840 Watts) versus a 120 Volt circuit (maximum of 1920 Watts).120 and also 240 Volt heaters space not interchangeable. A 240 Volt heater operation at 120 Volt will develop 25% the the rated wattage. A 120 Volt heater run at 240 Volt will be 4x 120 Volt rated wattage damaging the heater destroyed and poses a significant fire hazard.What voltage are my heaters?