In this article you will learn about replacing a electrical meter base for your home or business.

What is an electric meter base?
Your hydro utility connection has two parts, the meter and the meter base.
The electric meter is often referred to as the smart meter. This is round, enclosed in clear plastic or glass and measures electricity usage in kilowatt hours (kWh).
The meter base is typically a rectangular metal box mounted on the outside of your home or place of business. The meter base contains a socket in which the smart meter plugs into.
It is note worthy to mention that a hydro utility provider will not connect power to a damaged or improperly rated or incorrectly installed meter base. Hence the need for a meter base replacement.

Who owns the smart meter?
Your electrical utility provider owns the smart meter on your house. In the picture above the meter is owned London Hydro. They are responsible for installing, maintaining, and reading your meter. Your meter is sealed and designed with various features to prevent tampering.
Why you may need to replace your meter base
There are a few reasons as to why you may need to get your electrical meter base replaced. Hydro utility specification requirements, electrical code requirements and service upgrades are among the most popular reasons to changing a meter base.
Accessibility to connections
The load side of these connection points are in the home. Generally your electrical panel is in the basement in a mechanical room area. If a basement has been renovated getting access to some of the connection points can be difficult without opening up drywall or strategic wire fishing. Your job could fail a ESA inspection if the bonding and grounding isn’t up to code. If not corrected in a timely manner your hydro utility may not turn on your electrical service until the problem is fixed and inspected.

Why do I need to involve the hydro utility for a meter base change?
Changing out a meter base is a done with the electrical contractor and the Hydro provider. One of the requirements from your hydro utility provider is to provide the meter and installation specifications.
Many hydro utility providers are mandating that if a electrical panel is to be changed that the meter base must also be changed to meet its current specification requirements.
This is because some of the old meter bases currently in use are getting to an age that the utility companies don’t stock parts on their service trucks to fix them.
It has also been reported that some meter bases have burned up due to their age and the poor quality of the connection points.
Where to find specifications for installing a meter base?
Examples of Specifications and contractor installation information can be found on the hydro utilities website.
In my electrical service area for Green Electric & Automation, I use the following utility providers documents as they cover most of my clients. However it is important that you use your providers specs as the requirements can differ depending on your location and hydro provider.
Hydro One Networks
Specs for meter-base-sockets pdf
Electrical building information for builders and contractors
London Hydro
Full list of building specifications regarding hydro utilities. conditions of service pdf link
Installation specifications for meter base’s
You must comply to the specs. To avoid future issues, some utilities enforce replacement of old 100 amp meter base’s to a 200 amp rated per position meter base. This allows for parts availability should you need emergency service and ensures a good, clean electrical connection free of oxidization.
Why do we need meter base specifications?
The specifications outline what needs to be done in order to have a compliant meter base installation. Failure to follow the specifications could result in a loss of power or loss of re-connection to the electrical grid. By following the specifications it increases electrical safety and protects the public from hazards and loss of utility services.
Changing a meter base can be a big job.
In some case’s this could involve excavating a rather large pit around the meter base to allow for hydro technicians to splice service feed connections made below ground. The size of this pit will be listed as a spec. Its possible that the excavation of the pit could interfere with landscaping, a deck or paved driveway depending on where your meter base is located.
How long does it take to change a meter base?
Typically a meter base can be changed out in one day. But as you can guess some jobs may take longer. Jobs that can take longer could require more labor hours and cost.
These special requirements could be updating wiring to meet electrical code, extra machinery to excavate a pit or trench, wire locating, landscaping, driveway removal and patching and job site survey.

The photo above shows a old meter base awaiting replacement. Inside you can see a stamp where the rating of the meter base can be found. Normally this section of the meter base is locked out to authorized personal and is only accessible to the utility service technicians.
The reason this meter base was replaced was due to a electrical fuse panel needing replacement. This meter base was rated “100 amp max per position” and was replaced with a 200 amp max per position meter base.
By arranging a electrical survey you can have your hydro utility inspect the meter base for so you can determine if it is still compliant. If not acceptable it will need replacement when preforming a electrical service change such as a new service mast or panel swap.
Types of meter bases
There are several types of meter bases. They differ by rating capacity and positions. To know which type of meter base you require you have to consult your utilities specifications on their website.
One example of a specification is on the type of meter base you can install from a acceptability list. This means you can’t just use any meter base you want because you found it on sale or reuse a meter-base from another installation. You must use one that is listed on a acceptability list.
Mounting height for meter base
You may also need to cut or extend electrical conduits and pull new service wires to meet mounting height requirements of the new meter base. These requirements and more are referenced in the specs which can usually be found on your electrical utility providers website.
A meter base replacement can effect your neighbours electrical service
A meter-base replacement can get complicated if in a town house or semi configuration. The main issue is the requirement for a multiple position meter base.
This is needed when there is only one main service entering the meter base which then divides the power for each residential unit.
For example: A semi needs a 2 gang (2 position) meter-base or 3 unit townhouse needs a 3 gang (3 position) meter-base… etc.
Given notice and permission has to be gathered for the electrical service change as well as the costs to be shared among the unit owners or land lord. Sometimes getting a full buy in when multiple residents are effected can become a sticking point and stall a project before it starts.
What is a Disconnect – Inspect – Reconnect, “D.I.R”
A D.I.R is a work order carried out by the electrical contractor. It involves the hydro utility disconnecting your electrical service, a inspection of electrical work to be completed on the filed electrical permit and a re-connection of services by the utility after being approved by the electrical inspector.
Utility line disconnection point
The disconnection point of your hydro service may not be readily accessible. Usually when replacing a electrical panel the smart meter is disconnected by the utility and replaced with a blank cover. This is to prevent tampering inside the meter base while still allowing a safe, de-energized working area for the electrician to do the panel change.
Sometimes a proper disconnection at the meter base isn’t possible. In this case, the connected service wires can be taped. Optimally the electrical service should be disconnected at the road transformer or in a neighbors junction box. This could disrupt service to multiple houses if the junction box serves more then one customer.
Hydro site survey
In some rarer circumstances the connection point might be a buried junction box and require wire locating and excavation. Consulting your utility provider about getting a site survey preformed to see if there are any issues so that further delays don’t hinder a jobs completion.
Electrical code requirements
One requirement In getting a meter base changed is how the electrical system is bonded and grounded. This is sometimes over looked in a contractors estimate as the electrical bonding and grounding is not always easily visible and can require upgrading.
What is electrical bonding and why do I need it?
Electrical bonding is the wiring (usually #6 copper) that connects your gas line, and plumbing pipes of your home back to the electrical panel ground.
What is ground conductor?
When a electrical system is grounded, it refers to the main grounding conductor being referenced to physical earth. The ground wire is connected to either a grounding rod outside driven into the earth, a in-situ embedded in concrete or to a water supply pipe usually terminated before the water meter. A jumper is required between the meter in case the water meter is removed. The other end of the ground wire is terminated in the meter base.
When should you replace you meter base?
Every situation is different so getting a estimate is a good place to start. By getting the estimate you can review if the meter base actually even needs replacement. I would typically suggest replacing a meter base when you anticipate upgrading the main electrical service size, or when replacing a old fuse electrical panel.
When purchasing a old home factor into your budget replacement of the meter base if considering a electrical panel upgrade. Leave yourself time for planning, getting multiple estimates and financial reserves to cover the expenses.
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