Most people assume that the moment you turn off the main breaker within a building that the property has been completely disconnected from the national grid system. But this assumption is based on a fallacy. The power from the grid flows through high tension lines. From here, it passes into transformers before flowing into the local lines that feed your building. When you turn off the main breaker, that box is still connected to the grid. Therefore, residual energy can still pass through the system.
With more and more businesses turning to green energy as a source of power for their organization, there is a growing need to be able to safely disconnect a building from the feeder line. To do this properly, you need to use what is known as a disconnect switch. A disconnect switch is capable of completely interrupting the supply of power from the grid to the building or to a particular piece of equipment.
Here, we will detail the process of installing a disconnect switch as well as several of the many advantages.
Without a question, the number one advantage of using a purpose-built disconnect switch is safety. But not all disconnect switches are the same. With over 100 years of experience in the industry, Southern States equipment has met the requirements and standards of the appropriate regulatory bodies and can be trusted to provide safe and reliable equipment. After all, you cannot simply cut the wires at the transformer without risking the possibility of electrocution or starting a fire.
There are a number of different designs of disconnect switches that are available today. If you end up installing a disconnect switch, know that the type you use can depend on many factors. While the simplest forms are manually operated, the more advanced devices can be motor-driven as well as pneumatic and magnetic. Each type offers its own pros and cons, and not every type of switch is appropriate for all situations.
Manual or Powered
When deciding on installing a disconnect switch, you need to determine which type. The most basic form of a disconnect switch is a manually operated device that uses a swing handle to disconnect and then reconnect the circuit. A knife switch is a good example of a manually operated device. This allows you to completely disconnect a circuit from the grid. However, they are limited to the number of amps that can flow through them when connected.
From there we have manually operated devices that are operated similar to the round fuses that you screw into the back of your stereo. However, they are on a much larger scale. These types of devices generally use a pole and a hook in order to connect and disconnect them. They are safer than a swing handle system because the use of a long fiberglass pole provides more insulation from the power source.
Then we have powered systems that can use either motors in place of a swing handle or pneumatic actuators in place of a fiberglass pole and hook. Powered systems are generally reserved for higher amp draw systems such as substations and three-phase commercial feeds. After all, as the power through the switch is increased, so too is the danger of being electrocuted or starting a fire from the resulting arc.
More advanced systems can be found in several different form factors. The most common of these is the vertical break. However, depending on the situation a double-ended break, center break or even a side break switch may be more appropriate for your particular needs. It is always best to speak with a certified electrician. They will be able to offer guidance and insight regarding which particular system is best for your organization’s needs.
There really is a ton to know when it comes to installing a disconnect switch.
When installing a disconnect switch, you must also consider maintenance. The fact is, even small-scale businesses that have high power consumption needs also need to maintain their equipment in a safe and efficient manner. Machine shops, lumber yards, and other similar manufacturers often utilize a three-phase system and high-powered electrical motors that require routine maintenance.
Unlike a household appliance, this equipment is not plugged into an outlet. Instead, they are connected directly into the power system of the building. In order to safely maintain these machines, its common to have a specially designed breaker system for each individual unit. These allow an organization to completely disconnect any power flowing to the equipment. This way the equipment can be maintained properly, safely, and efficiently.
While there are a wide variety of different disconnect switches that are available, they all serve the same purpose; to completely isolate the circuit of the machinery from the mains power. Whether using a basic knife switch or isolator, it is important to ensure that when any piece of machinery is being maintained, there is no residual current flowing through the wires or the chassis of the equipment.
Pros of Installing a Disconnect Switch – Summary
In the end, every organization is different. Therefore, the needs of your organization are not going to be the same as another. This is true even if you are in the same industry. Above all, safety should be the most important factor taken into consideration when choosing a power disconnection system and installing a disconnect switch.