Electrical safety devices

Figure 1: A fuse box in a basement[1] is one type of electrical safety device.

We use electricity for many of the energy services around the house. Because of this, it is extremely important to have various safety devices to protect from fire and electrocution. Industrial electricity use has similar problems. This page examines these electrical safety devices. Namely, fuses, circuit breakers, and ground fault circuit interrupters. For more details, please go to the main articles.

Both fuses and circuit breakers are the connection point between the electrical grid and an individual house, for more details please see Connecting homes to the electrical grid.

Fuse

main article

A fuse is an electrical safety device that has the capability to protect a circuit from excessive current. It is designed to allow current through the circuit, but in the event that the current exceeds some maximum value it will open, severing the circuit.

Circuit breaker

Figure 1: A circuit breaker box.[2]
main article

Circuit breakers are devices that protect circuits from overload current conditions. They do the same job as fuses, but they are not destroyed when activated. They are more expensive to put in than fuses, but since components rarely need to be replaced may be cheaper in the long term. Circuit breakers are often considered safer since the user can't as easily disable them (like putting the wrong size fuse in place).

Circuit breakers functionally open a switch which turns off all the electrical current before the excess electrical current can start a fire. Before resetting the circuit breaker, always turn off or unplug the electronic devices that were being used with the breaker was activated.

Ground fault circuit interrupt

Figure 1: A GFCI plug.[3]
ground fault circuit interrupter

A ground fault circuit interrupt is a device designed to detect a tiny mismatch in currents (going into and out of the circuit), in order to prevent electrocution. They are mandatory in bathrooms and kitchens, and anywhere else in a house where water may come in contact with an electric circuit.[4]

References

  1. This picture contributed by someone on the energy education team.
  2. By BrokenSphere (Own work) [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons Wikimedia Commons [Online], Available: https://upload.wikimedia.org/wikipedia/commons/6/62/Eaton_circuit_breaker_panel_open.JPG
  3. Wikimedia Commons [Online], Available: https://commons.wikimedia.org/wiki/File:GFCIReceptacle.jpg
  4. R.T. Paynter, “Basic Electric Components and Meters,” in Introduction to Electricity, 1rst ed. NJ: Prentice-Hall, 2011, ch. 8, sec. 8.2, pp. 341-346.

Authors and Editors

Jordan Hanania, Braden Heffernan, James Jenden, Kailyn Stenhouse, Jasdeep Toor, Jason Donev