A listing of approved meter stacks can be found in the "Approved Meter Sockets", Requirement 13.42 through 13.50 .

It shall be the responsibility of the Customer to obtain GPU Energy approval for group metering (meter stacks) prior to purchase and installation.

The Customer shall be responsible to permanently mark each socket both on the outside of the meter cover and on the inside of the meter socket. See figure in Requirement 12.68 .

All group metering (meter stacks) installed for 120/208 volt single-phase services, shall be equipped with a fifth terminal or jaw preferably located in the 9 o'clock position.

It is the Customer's responsibility to have stacks, including the meter mounting portion, maintained in a safe and operational condition in accordance with all applicable national and local codes.

For more information on Group Metering Requirements, See Requirements 4.30, 4.35 & 4.40 .

In each case where multiple service enclosures are contemplated, the Company must be consulted for approval of any such installation.

Where multiple service enclosures for an individual customer are to be supplied from one overhead service drop or lateral, and the total anticipated load current is in excess of 400 amps, the Company will supply "window" type current transformers (CT's) for installation at the service drop attachment location. See figure in Requirement 12.70 . These CT's will be installed by the Customer at the direction of the local Meter Department (in some areas of the Company, GPU Energy installs the CT's). The electrical contractor will furnish and install a 1 1/4 inch minimum rigid conduit from the transformer to the meter socket. The meter socket will be supplied by the Company and installed by the Customer.

In those cases where multiple service enclosures for an individual customer are to be supplied from one overhead service drop or lateral, and the total anticipated load current is less than 200 amps, the Customer must provide for the metering of all use through one self-contained meter, or must provide for individual meters for each service enclosure. Where more than one meter is installed, the use registered by each meter will be billed separately. Examples of residential installations where two meters are permissible would include a separate apartment attached to a single family home, a doctor's office attached to a residence, and non-commercial loads used on the premises in conjunction with the operation, use, and maintenance of an individual residence, such as swimming pool pumps, heaters, saunas, garages, etc. However, the addition of a second meter will not be permitted off the same service, for the same customer in order to avoid a service upgrade.