Electrical Service is the term used to describe the point at which power enters your home. This may be by way of overhead wires or an underground service lateral. In either case, the conductors that come from the utility pole, pedestal or ground-mounted transformer connect to a metal service entrance cable (typically gray) which runs down an exterior wall to a meter base that is attached to the electric meter. The meter is then connected to the main service panel inside your home.
Whether a homeowner is considering adding a new appliance or simply extending their current circuits, it’s important that they understand the capacity/limitations of their existing electrical service. If you are not familiar with how the system works, it is easy to over-estimate what your home’s needs are and end up in an expensive disaster.
The first thing to consider is how much electricity your home consumes on a regular basis. This includes things such as lights, appliances and heating/cooling. It is also important to consider seasonal variations. In the winter, more heat will be required which can put a strain on the system and in the summer a home’s cooling demands will increase. All of these factors will affect the size of your service and should be taken into consideration when making a change to your electrical system.
There are many different types of electrical services available to homeowners in the US. For the most part, residential homes will have a single phase 208Y120 electric service. This type of service has two insulated lines that carry 240V and one bare line that is bonded to ground. The insulated lines are used to power the larger loads in your home such as air conditioners, electric water heaters and dryers. The standard 120V is then available to outlets throughout the home.
When looking at your electric meter base, you will notice that it has an integrated service disconnect (ISD). This is an important safety feature since the ISD will kill all of the voltage to the conductors on your service drop (the wires from the utility pole) before the service entrance cable enters your home. This allows the fire department to cut off your power from outside of your home without having to enter and spray water on any live wires.
Once the ISD has been activated, there will be a meter that is attached to the ISD which will give you your readings and how much energy your household uses on a monthly basis. The meter will also have a key lock on it that can only be opened by a certified ComEd customer service representative. It’s also important to note that it is not a good idea to try and do any work on your own on the buried portion of the service drop. This is because if you damage the line it could cost you thousands of dollars in repairs and potential dangers to yourself, your family and/or your neighbors.