Please Explain Small Gauges of Extension Cords

Users who are viewing this thread

JWelectric

Electrical Contractor/Instructor
Messages
2,608
Reaction score
21
Points
38
Location
North Carolina
Any appliance is tested by the NRTL by the intended use of the appliance. Take a drip coffee maker of 1200 watts. For the amount of time that the coffee is making the appliance is pulling maximum current but the minute the coffee is made the heating element that is used to boil the water turns off and the coffee maker is pulling half the current.

The portable electric heaters are not designed to heat out homes. They are designed to reach a temperature and then shut off. It is when we try to use an appliance outside its scope that we start having trouble out of the appliance.

Any load that continues for a period of more than three hours is mandated to be calculated at 125% of it rating. In other words a light that pulls one amp that is on for more than three hours must be calculated at 1.25 amps. The same is true for resistive loads such as portable heaters no matter how long they are in use.

The reason for this is for the dissipation of heat. When heat is applied to something for more than three hours or in a resistive load it continues to rise at a greater degree than if it was being used at short intervals.

These portable electric heaters are designed to reach a preset temperature and then shut off for a period of time. When we try to use one to heat a room and the heater is too small it will continue to run thus the overheating of the end cap and the resulting fire.

By observing a couple of rules these heaters can be fairly safe. First never set one on high for more than thirty minutes and then turn it too low for a while. Never leave one unattended even for a few seconds. This rule applies to the burner of a cook stove. Never and I repeat never use an extension cord to supply a portable electric heater no matter the size of the cord. The added series resistance of each plug will cause a voltage drop and will result in heat in the end cap. Keep the heater at least 36 inches from anything that will catch fire.

If one heater will not keep the area warm when set to its lowest setting then the heater is too small for the intended job.
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks