heat dissp. of electric cables

[saliba11]

what is the heat dissipation of electric cable having the size 1000 watt.

Does it neglectd in HVAC calculations or not.

your kind response is appreciated.

best regards

 

[MintJulep]

Cables are typically not rated in watts.

To figure out how much heat is dissipated from a cable, you need to know the current flowing in the cable, and the cable resistance per unit length.

Power dissipation would then be

P=I²RL

Where L is the length of cable in the space you are concerned about.

 

[gepman]

Another way of calculating the heat loss would be to obtain the voltage drop on the cable. The power loss on the cable would be P=IDeltaV where I is the current and Delta V is the voltage drop.

As MintJulep said conductors are not rated in watts but have an ampacity. A cable rated in watts sounds like a heat trace cable or other heating cable which would actually produce that amount of heat. The rating is usually in watts per foot or other unit of length.

Electrical distribution systems are usually sized for no more than 3% voltage drop over the entire branch circuit. I usually neglect this heating in my load calculations since it is small and my estimates for other sources are not this accurate.

If you are dealing with three phase loads make certain you use the correct formulas for three phase loads.