Duquesne Light > Customer Services > Connecting Service > Electric Service Installation Rules >

Services Not To Be Grounded

The following types of service will be normally supplied ungrounded. The Customer shall not ground the conductors of these installations without specific written permission from the Company.

Phase	Wires	Voltage
1	2	230
1	2	460
3	3	230
3	3	460
3	3	2,400
3	3	23,000
3	3	69,000
3	3	138,000

Grounding Electrode Conductors

The grounding electrode conductor size shall be not less than No. 6 copper or aluminum. Larger services shall have grounding electrode conductors sized as specified in article 250-94 of the National Electrical Code. NEC Article 250-23 shall determine where the grounding electrode conductor is connected to the grounded service conductor, except that the meter enclosure (base) shall not be used for this connection because it is not accessible when sealed.

Primary Water Pipe Electrode

The grounding electrode conductor shall be run without splices or joints to a continuous metallic underground water piping system if available. All parts of the water piping system that are likely to become disconnected, such as water meters or service unions, shall be suitably bonded.

The grounding electrode conductor shall be connected to the metal water piping system in the building if one is available. If the water utility does not permit grounding to its system, an insulating bushing may be used outside the building.

Supplemental Electrodes

The metal water piping system shall be supplemented by two electrodes of the type specified in Article 250 of the National Electrical Code. The grounding electrode conductor shall be extended without splices to these electrodes. The supplemental electrodes will become the primary electrodes if a metallic underground water pipe system is not available.

ACCESS TO CUSTOMER'S PREMISES

Company representatives, who are properly identified, shall have the full and free access to the Customer's premises at all reasonable times for the purpose of reading meters, for inspection and repairs, for removal of Company property, or for any other purpose incident to the service. The Customer should immediately check with the Company if the credentials of Company representatives are in question.