Showing posts with label Electrician Rockville Md.. Show all posts
Showing posts with label Electrician Rockville Md.. Show all posts

Sunday, July 5, 2009

Everything You Always wanted to know about a Heavy Up








Everything you wanted to know about a Heavy Up?
Replacing the electrical panel in your home.
Cary Electric Company http://www.caryelectriccompany.com/



People have the size of their electrical service increased for many reason; in the electrical industry this Process is called a Heavy-Up. The reason most people ask for Heavy-ups are they either want to do away with their old fuse box because they never know which fuse has blown or they are in the process of adding Additional circuits for a new room or installing a Hot-Tub or another high power consuming appliance or apparatus, or they are experiencing problems with their old panel the bus-bar, pull-outs, fuse sockets are burned and causing problems and could become a potential danger to the household.

The first thing any homeowner should do is ask if the Contractor is licensed and insured, If you have questions or concerns about your contractor always check with the local inspection authority, in Montgomery County Maryland the Tel Number is 240-777-6240, ask if there are any outstanding violations on the Contractor you select. Remember any time you replace the Main Electrical Panel in your home it requires a Permit and must be inspected by the local authorities and the Power Company must be notified so they may increase the service to the property in many cases it requires a new Meter Socket and a new lateral drop from the power company.

The next step is to talk to the contractor to decide what size service your needs require. The minimum size service in the National Electrical Code is 150 Amps. The codes (NEC) also require a Main disconnect and the new Service must be properly grounded and The Panel must be bonded to the Neutral Bar.

The third step in the process is to drive a ground Rod 10 feet into the earth, the NEC requires a minimum of 25-ohms resistance to ground and it has been determined by the National Fire Protection Association that either a nickel or copper rod driven 10 feet into the earth or 25 feet of #4 copper wire laid in the foundation of the building will provide the minimum 25- ohms resistance, necessary to ground an electrical system. In a new home both grounding systems are required.

The next step is to install the Service Drop or Service Entrance Cable (SEC), this is the main cable that runs down the outside or your home and goes to your meter and then to your Main Panel. Remember the SEC must be properly sized for a 150-amp service you need a minimum of 2-0 conductors for a 200 amp panel you need a 4-0 conductor. Always remember electricity does not run threw a conductor but rather around it, the larger the size of the conductor the more amperage may travel around the conductor. The National Fire Protection Association has developed a scale called the American wire gauge and has created a table that is published in the




NEC table 310-16 to help you determine the proper size conductors needed for specific amperage needs.






Then we start with the panel: the first step is most always laying out the job, After you already know the size of the new service you must integrate the existing wiring to the new panel configuration, I always start by stripping the panel that means to remove all wires from the existing panel. Then I size up the new panel with the existing wires, this is tricky, your goal must be to have as few splices in the new panel as possible, remember every connection is a potential future breakdown so take your time when you size the new panel with your existing wiring.

Next I install the new panel always remember to first bond the panel to its neutral bar. The neutral bar is the terminal that hold both your equipment grounds ( the shell of all apparatus) and your neutral conductors. And remember always try and make your work as neat as possible, if you take the time to make your job neat then most likely you will also make sure all connections are tight and less likely to ever pose a problem for the customer. You then install the circuit breakers carefully making sure you install the proper size breaker, matching the amperage size to the size of the wire. Remember electricity runs along the outside of the wire so its critical not to oversize the circuit breaker. The last part of a heavy- up is to install the Water Ground; we must always install a ground between the water pipe, near and before the main shut off to the Neutral Bar in the panel. Also if the home has a Water Meter inside the house, remember you must install jumpers across the water meter so as to protect a Plumber in the future is there is a fault. You do not want the Plumber to become the conductor to ground.
Finally you must properly mark the panel for all major appliances and general lighting circuits and appliance circuits. A properly labeled panel will reduce aggravation and stress on the Homeowner in the future.

Cary Lamari