11.1 General
In case of consumers of Category I to IV(as defined in Chapter 2) where line voltage (11000 volts or higher up to 132kV) is stepped down on the consumer's property to the service voltage required by the consumer, the facilities necessary to accommodate the transformer or transformers and the related equipment will be either:
a) A Distribution Sub Station, if furnished, installed, owned, and maintained by the DISCO, or
b) A Consumer Sub Station, if furnished, installed, owned, and maintained by the consumer.
11.2 Distribution Sub Station
The DISCO will install a Sub Station for such General Purpose consumers.
The DISCO shall ensure that all the installations are in accordance with the DISCOs approved design specifications and standards.
11.3 Consumer Sub Station
The responsibility for the provision of space, installation and maintenance of step down transformer and all allied equipment in a consumer sub station shall be that of the consumer. The layout of the sub station, the equipment installed must meet the specifications, design and standards as approved by the DISCO. The equipment may be supplied by the DISCO on payment. However, for such facilities, the responsibility of the DISCO shall only be up to the metering point (Interconnection point).
For such installations, the consumer shall provide land/space for the lines which will extend to and from the sub station and obtain consents, way-leaves and authorizations pertaining to the right of way.
11.4 CONSUMER OWNED GRID STATION
Consumers of Category V (for supply at 66 kV and above) shall at their own sole risk and expense, furnish, install and maintain in good and safe condition all electrical wires, lines, machinery and apparatus of any kind or character which may be required for:
a) Receiving electrical energy from the DISCO/NTDC system; and
b) Utilizing such energy, by installing step down transformer and all other allied accessories and equipment including protection devices at the consumer premises.
c) The consumer will be responsible for the payment of construction charges and all costs associated with line extensions payable as per provision laid down in the Consumer Eligibility Criteria.
d) The design of the station shall conform to DISCO/NTDC design practices, guidelines and applicable safety codes.
11.5 Metering Equipment and Installation Requirements
a) Meter installation shall comply with Pakistan Standard Institute (PSI) or International Electric Technical Commission (IEC) standard or Standards developed/adopted by the DISCO /NTDC.
b) The DISCO/NTDC shall determine the location and method of installation for all metering equipment as provided in the distribution code, Grid Code and related manuals.
c) Whenever any electrical wiring is modified, new metering equipment complying with these service requirements shall be used, except when in the opinion of the DISCO/NTDC the existing metering equipment is satisfactory and adequate to register all energy to be supplied.
d) Line side (unmetered) conductors and load side (metered) conductors are prohibited from occupying the same enclosure.
11.6 GROUNDING SYSTEM
As defined in Distribution Code, Grid Code and the PSI Wiring Regulations, proper neutral and protective earthing/grounding system shall be installed by the consumer and checked by authorized representative of DISCO and NTDC.
11.7 FIRE EXTINGUISHERS
Suitable fire extinguishers shall be provided and maintained by the owner agency to meet with any hazardous situation.