D.I.Y., TYPICAL 200-AMP RESIDENTIAL SERVICE CHANGE OUT

Service configurations may vary from home to home, but all have similar characteristics.  We will discuss the most common service changes and you will have to adapt these principles to your unique situation.

Let me state at this juncture, that service changes require the power to be removed from your home and the work inspected by professionals before it is restored.  If you do not feel completely comfortable in your work passing inspection you should leave it to an electrical contractor.

The sequence of steps required before a Service Change, are:

1. Determine that you need a service upgrade (see “D.I.Y., So You Think You Need An Electrical Service Change?”).
2. Formulate a plan: Design it on paper, list all tools required, line up physical help (you will need it on the change out day),  list all materials required (remember, the smallest, cheapest part could cost you an inspection approval).
3. Contact your power company representative to make sure he approves of your plan.
4. Pull a permit to do the work.
5. Purchase all materials.
6. Contact the power company and set an appointment for the power to be removed from your home.
7. Contact the inspection department and schedule the inspection for late in the same day.

Suggestion:

A day or two before the service change, lay all of the components of the service change out on a garage floor and double check your plan for parts and required tools.

A.  2″ Service Head – Protects from water intrusion into conduit.

B.  2″ Roof boot with tar – Protects from water intrusion into roof.

C.  2″ Hardwall straps – Must be securely fastened into wall and firmly supporting the riser.

D.  2″ Galvanized conduit with three 2/o THHN Copper wires called riser.

E.  2″ Hub securely mounted into the meter socket – The conduit is screwed into the hub protecting from water intrusion into meter socket.

F.  Meter Socket – Your power company may furnish free of charge, or you may have to purchase from supply house.  The center of the meter opening must be 5 ft 6 in off the finished ground level.

G.  Protective cover over branch circuit conductor entering the panel.  This may be made of wood, drywall or metal.

H.  Romex cable connectors – Protects multi-circuit cables as they enter the panel.  The cables must also be stapled within 6 inches of the panel.

I.  200-amp/single-phase/main breaker distribution panel, with breakers and grounding bar.  Panel must be mounted above the flood zone level of the home, with the main breaker 6 feet or lower, off the finished floor.

J.  2″ nipple with locknuts and bushing on either end, securely installed.  You may use a PVC or metal nipple.

K. The grounding system – It must contain:

• 1/2″ PVC with one #4 CU wire from grounding terminal; in the meter, to ground rod(s) and/or footer rebar and cold water copper pipe.

• Grounding bar with #6 copper wire terminated at ground rod or any       grounding terminal.  This provides a grounding screw for termination of  phone or TV entrance cables grounding conductors.

• Two sources of earth grounding must exist.  In newer homes a rebar      ground may be available.  In homes with copper plumbing pipes the        cold water pipe must be one of the two ground points. Two ground rods may also be driven (5/8″ in diameter X 8 feet).  They must be sepa-        rated by at least 6 feet, with a #4 copper wire attached by proper-sized  ground lamps.  The wire must be continuous from the meter and not      spliced at any point.

Sequence of steps for the Service Change:

1.  The power company arrives and will disconnect the power lines.

2.  Mark or tie together all 240-volt circuits, as you remove them from the old fuses or breakers.  Remember, a 20 or 30-amp, 240-volt circuit will have a hot white wire.  This will prevent you from mixing them up with neutrals.

3.  Remove all components of the old service, not to be reused.

4.  Install meter socket:

• Hub
• Riser conduit (strap in place)
• Nipple, locknuts, bushings
• Panel
• Grounding system
• Feeder wires: Phase A and B (hot) and neutral (marked with white tape)
• Service head
• Reinstall using approved connectors all existing branch circuit wires (Romex cable/multi-conductor cables)
• Breakers
• Tie in hot wires to breakers
• Tie in neutral wires to neutral buss bar
• Re-torque all terminals (every wire must be tight under lugs)
• Close up panel (dead front and covers)
• Mark breakers as to what they will control

5.  Inspector will inspect and call power company.

6.  Power company will return and re-energize.

7.  Test all circuits.

8.  Clean up.

You’re Done!

Romex is a registered trademark of Southwire Company.

• Related articles

• D.i.y., So You Think You Need an Electrical Service Change? (electricauthority.org)
• D.i.y., What Size Wire to Use? (electricauthority.org)
• D.i.y., Questions to Ask? (electricauthority.org)
• D.i.y., Appliance Wiring (electricauthority.org)
• D.i.y., Adding a Receptacle (electricauthority.org)