Electrical Power Systems: Power Distribution Safety Components

Electrical power systems involve the processes of generating, transmitting and distributing power. Although these processes are a mystery to most people, many are unknowingly familiar with power distribution in the forms of residential “power lines” and “panelboards“. Those that are familiar with these components also know that they can be extremely dangerous, as can electricity in general.

It is interesting to discover however, that within the distribution component of electrical power systems, there are countless inbuilt high-tech safety devices which allow energy to be carried safely to the end user. A few of these devices will be discussed in this paper, the first of which can be found at large power substations, where the distribution segment of the energy supply chain begins.

Safety Devices Implemented in the Distribution Component of Electrical Power Systems

At large substations the transmitted energy which is generally conveyed at about 35,000 volts is brought down to about 7200 volts via a transformer. On either side of this transformer are safety devices called switchgears. On the high voltage side of the transformer is high voltage switchgear which can handle voltages over 35,000, on the lower voltage side of the transformer in comparison is medium voltage switchgear which can handle between 1000 and 35,000 volts depending on the design.

These devices are basically comprised of circuit breakers, fuses and safety relays, which have the ability to shutoff power to components in the event of an overload or a short circuit. Switchgears also make it possible for technicians to control the power to various components within the substation, thereby allowing for safe repairs to be undertaken.

After the energy has been transformed at the substation it is then further dispersed via the distribution bus, with the aid of lower voltage lines. These lines then carry the energy to other substations, and surrounding residential, commercial and industrial facilities, as well as to infrastructural installations. When the energy reaches its destination it is once again downgraded to an even lower voltage depending upon its intended usage.

In industrial situations a voltage higher than that used in residential conditions is often required, due to the presence of energy hungry equipment and complex mechanical processes. For this reason the energy entering an industrial complex will usually meet with either low voltage switchgear or a switchboard. These two devices are quite similar in construction however; switchboards can only deal with approximately 600 volts depending on the internal components, whilst low voltage switchgear can usually handle up to 1000 volts. Both switchboards and low voltage switchgear are similar in function safety-wise to medium and high voltage switchgear.

When energy reaches a residential setting however, it is normally dropped to 240 volts and therefore comes into contact with a panelboard, which is basically a less complicated switchboard. The most that many people have to do with this device however is flicking a switch when the circuit breaker has been ‘tripped’, which generally occurs in these settings due to an overload. Little do they know however, that devices similar to this have been ensuring their safety by regulating their power along its entire route.