GRID CODE
VERSION 9
Approved by OERC

CONTENTS

GRID CODE REVISION SCHEDULE

1. INTRODUCTION

2. DEFINITIONS

3. MANAGEMENT OF THE ORISSA GRID CODE

4. SYSTEM PLANNING

5. CONNECTION CONDITIONS

6. OUTAGE PLANNING

7. SCHEDULE AND DESPATCH

8. FREQUENCY AND VOLTAGE MANAGEMENT

9. MONITORING OF GENERATION AND DRAWAL

10. CONTINGENCY PLANNING

11. CROSS BOUNDARY SAFETY

12. OPERATIONAL EVENT/ACCIDENT REPORTING

13. PROTECTION

14. METERING, COMMUNICATION AND DATA ACQUISITION

15. DATA REGISTRATION

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GRID CODE REVISION SCHEDULE

1.1. General:
Transmission and Bulk Supply License requires the Licensee to prepare, and at all times have in force, a Grid Code that shall include Sections on:

1. Planning: specifying the technical and design criteria and procedures to be applied by the Transmission Licensee (Licensee) in the planning and development of the Transmission System and by other Users connected or seeking Connection to the Transmission System;

2. Connection: specifying the technical design criteria and standards to be complied with by the Licensee and other Users connected or seeking Connection to the Transmission System;

3. Operations: Specifying the conditions under which the Licensee shall operate the Transmission System and other Users of Transmission System shall operate their plant and/or systems for the generation and distribution of electricity in so far as necessary to protect the security and quality of supply and safe operation of the Licensee's Transmission System under both normal and abnormal operating conditions.

4. Outage: specifying the procedures relating to co-ordination of the Outages for scheduled maintenance of the Transmission System, Generating unit and Distribution System that will use the Transmission System;

5. Schedule and Dispatch: Specifying the procedures to be followed by the Licensee and Users relating to the scheduling and dispatch of Generating Units to meet State demand and Drawal allocation.

6. Metering: specifying the minimum operational and commercial metering to be provided by each User.

7. Protection: specifying the co-ordination responsibility and minimum standards of protection that are required to be installed by Users of Transmission System.

The Grid Code is a document that governs the boundary between the Licensee and Users and establishes procedures for operations of facilities which will use the Transmission System. It lays down both the information requirements and the procedures governing the relationship between the Licensee and Users. It should be noted that the Grid Code is not concerned with the detailed design and operation of Generators’ Power Stations and Suppliers’ Distribution Systems, provided that their overall compatibility with the Transmission System needs is assured.

The Transmission and Bulk Supply Licence requires that the Licensee in preparing, implementing and complying with the Grid Code shall neither discriminate against nor unduly prefer any one or any group of Users.

The Grid Code shall cover all material technical aspects relating to Connections to and operation and use of the Transmission System including the operation of electric lines and electrical plant connected to the Transmission System in so far as is relevant to the operation and use of the Transmission System. It shall be designed so as to permit the development, maintenance and operation of an efficient, co-ordinated and economical system for the transmission of electricity in the State.

1.2. Scope:
The Grid Code shall be complied with by GRIDCO in its capacity as holder of the Transmission and Bulk Supply License and by Generators, Distribution Companies, Suppliers and Bulk Power Consumers in the course of their Generation, and Supply, and utilisation of electricity.

1.3. Interpretation:
The meaning of certain terms (which are printed in bold letters and capitalised) used in the Grid Code shall be in accordance with the definitions listed in Section 2, "Definitions", of the Grid Code.

Section 2 of this code has been developed on the premise that accepted engineering terms do not require additional definitions.

The term "Grid Code" means any or all parts of this document.

1.4. Implementation and Operation of the Grid Code:
The Licensee has the duty to implement the Grid Code. All Users are required to comply with the Grid Code which will be enforced by the Licensee. Users must provide the Licensee reasonable rights of access, service and facilities necessary to discharge its responsibilities in the Users’ premises and to comply with instructions issued by the Licensee, reasonably required to implement and enforce the Grid Code.

If any User fails to comply with any provision of the Grid Code, it shall inform the Licensee without delay of the reason for its non-compliance and shall remedy its non-compliance promptly. Consistent failure to comply with the Grid Code may lead to Disconnection of the User’s plant and/or facilities.

The operation of the Grid Code will be reviewed regularly by the Grid Code Review Panel in accordance with the provisions of the relevant Section of the Grid Code.

1.5 General Requirements:
The Grid Code contains procedures to permit equitable management of day to day technical situations in the Electricity Supply System, taking into account a wide range of operational conditions likely to be encountered under both normal and abnormal circumstances. It is nevertheless necessary to recognise that the Grid Code cannot predict and address all possible operational conditions.

Users must therefore understand and accept that the Licensee in such unforeseen circumstances may be required to act decisively to discharge its obligations under its Licence. Users shall provide such reasonable co-operation and assistance as the Licensee may request in such circumstances.

1.6. Code Responsibilities:
In discharging its duties under the Grid Code, the Licensee has to rely on information which Users supply regarding their requirements and intentions. The Licensee shall not be held responsible for any consequences that arise from its reasonable and prudent actions on the basis of such information.

1.7. Confidentiality:
Under the terms of the Grid Code, the Licensee will receive information from Users relating to their intentions in respect of their Generation or Supply businesses. The Licensee shall not, other than as required by the Grid Code, disclose such information to any other person without the prior written consent of the provider of the information.

1.8. Procedures to settle dispute:
In the event of any dispute regarding interpretation of any part of the Grid Code provision between any User and the Licensee, the matter may be referred to the Commission for its decision. The Commission’s decision shall be final and binding.

In the event of any conflict between any provision of the Grid Code and any contract or agreement between the Licensee and a User, the provision of the Grid Code will prevail.

1.9. Communication between Licensee and Users:
All communications between the Licensee and Users shall be in accordance with the provisions of the relevant Section of the Grid Code.

Unless otherwise specifically required by the Grid Code, all communications shall be in writing, save that where operation timescales require oral communication, these communications shall be confirmed in writing as soon as practicable.

1.10. Partial Invalidity:
If any provision or part of a provision of the Grid Code should become or be declared unlawful for any reason, the validity of all remaining provisions, or parts of provisions, of the Grid Code shall not be affected.

1.11 Directive:
Under the provisions of the Act, the State Government. may issue policy directives in certain matters. The Licensee shall promptly inform the Commission and all Users of the requirement of such direction. The directions will be complied by the Users subject to Section 12(2) of the Act.

¹[1.12
Gridco being the State Transmission Utility (STU) is responsible for making the Orissa Grid Code consistent / compatible with the IEGC. in the event of any further inconsistencies, the provisions of IEGC shall prevail.]

2. DEFINITIONS

3. MANAGEMENT OF THE GRID CODE

3.1 Introduction:
Under the terms of the Orissa Transmission and Bulk Supply License, condition 17, Licensee is required to implement and comply with the Grid Code and periodically review the same and its implementation. For the above purpose a Grid Code Review Panel comprising representatives of all Users of the Transmission System shall be established.

Subject to the conditions in the next paragraph of this Section, a specific and important feature of the Grid Code is that no revision or modification of the Code, however large or small, may be made without being discussed at the Grid Code Review Panel meeting and approved by the OERC.

The OERC may issue directions requiring the Licensee to revise the Grid Code in such a manner as may be specified in those directions and the Licensee shall promptly comply with any such directions.

This document defines the procedure to be followed by the Licensee in maintaining the Grid Code and also in pursuing any change.

3.2 Objective:
The objective of this procedure is to define the method of managing the Grid Code, submitting and pursuing of any proposed change to the Grid Code and the responsibilities of all Users to effect that change.

3.3 Responsibilities:
The Licensee will be responsible for managing and servicing the Grid Code for discharging its obligations under the Licence.

The Licensee shall establish and service the requirements of the Grid Code Review Panel in accordance with provisions of Section 3.4 of the Code.

3.4 Grid Code Review Panel:
The Licensee will inform all Users of the names and addresses of the Panel Chairman and Member Secretary at least seven days before the first Panel meeting, and shall inform Users in writing of any subsequent changes.

Each User shall inform the Panel Member Secretary of the name and designation of their Panel Representative not less than 3 days before the first Panel meeting and shall inform the Panel Member Secretary, in writing, of any subsequent change.

The Panel shall be chaired by Gridco in its capacity as the transmission Licensee and consist of the following members:

1. A Chairman who is an officer from GRIDCO.

2. A Member (Secretary) who is an officer from GRIDCO.

A single representative from each of the following:

3. One member from OHPC.

4. One member from OPGC.

5. One member from TTPS (NTPC)

6. One member from Power Grid (ERLDC)

7. One Member from ¹[major CPPs (with installed capacity exceeding 50 MW), connected to the Licensee’s Transmission System, for tenure of one year each on rotation basis to be notified by the Licensee, to represent all the CPP in the State].

8. One member from each of the Distribution Companies

2[Further, one representative from EREB may participate in the Review Panel as a special invitee]

⁴[One representative from OERC may attend the meeting as an observer.]

The Rules to be followed by the Panel in conducting their business shall be formulated by the Panel themselves and shall be approved by the OERC. The Panel will meet at least once in ⁵[six] months.

The functions of the Panel are as follows:

1. To keep the Grid Code and its workings under scrutiny and review.

2. To analyse any major grid disturbances soon after the occurrence and evolve any consequent revision to the Grid Code.

3. To consider all requests for amendment to the Grid Code which any User makes.

4. To publish recommendations for changes to the Grid Code together with the reason for the change and any objections, if applicable.

5. To issue guidance on the interpretation and implementation of the Grid Code.

6. To examine problems raised by Users.

Sub-meetings may be held by the Licensee with a User to discuss individual requirements and with groups of Users to prepare proposals for the Panel meeting. The Panel may set up sub-committees for detail studies of related problems.

3.5 Grid Code Review and Revisions:
The Member Secretary shall present all proposed revisions of the Grid Code to the Panel for its consideration.

The Licensee shall send to the Commission following reports at the conclusion of each review meeting of the Panel.

1. A report on the outcome of such review.

2. Any proposed revisions to the Grid Code as the Licensee reasonably thinks necessary for the achievement of the objectives referred to in Sub-paragraph (b) of Paragraph 17.1 of the Transmission and Bulk Supply Licence.

3. All written representations or objections from Users arising during the review.

All revisions to the Grid Code shall require approval of ¹[the] Commission. The Licensee shall publish revisions to the Grid Code once approved by the OERC.

The Licensee shall present proposals to the OERC to allow relaxation, where Users have difficulties in meeting the Grid Code requirements.

The revision number and date of issue shall appear on every ²[relevant] page ³[pages] of the Grid Code.

Every change from the previous version shall be clearly marked in the margin. In addition, a revision sheet shall be placed at the front of the revised version that lists the number of every changed sub-Section. ¹[-------------] The Licensee shall keep an up-to-date list of the recipients and locations of all serviced copies of the Grid Code.

4.1 Introduction:
This Section identifies the method for data submissions by Users to the Licensee for the planning and development of the Transmission System. This Section also specifies the technical and design criteria and procedure to be applied by the Licensee in the planning and development of the Transmission System.

A requirement for reinforcement or extension of the Transmission System may arise for a number of reasons, including but not limited to the following.

1. Development on a User’s system already connected to the Transmission System.

2. The introduction of a new Connection point between the User’s system and the Transmission System.

3. A general increase in system capacity to remove operating constraints and maintain standards of security.

4. Stability considerations.

5. Cumulative effect of any of the above.

Accordingly, the reinforcement or extension of the Transmission System may involve work at an entry or exit point (Connection point) of a Generator or Distribution Company to the Transmission System.

Since development of all Users’ systems must be planned well in advance to permit consents and wayleaves to be obtained and detailed engineering design/construction work to be completed, the Licensee will rquire information from Users and vice versa. To this effect the Planning Code imposes a time scale, for exchange of necessary information between the Licensee and Users having regard, where appropriate, to the confidentiality of such information.

4.2 Objective:
The provisions of this section are intended to enable the Licensee in consultation with Users, to provide an efficient, co-ordinated, secure and economical Transmission System to satisfy requirement of future demand.

4.3 Perspective Plan:
4.3.1 The Licensee is charged with the responsibility to prepare and submit a long term (10 years) plan to the Commission for generation expansion and for Transmission System expansion to meet the future demand under condition 20 of the Licence.

4.3.2 For fulfilment of the above requirement the Licensee shall:

1. Forecast the demand for power within the Area of supply in each of the succeeding 10 years and provide to the Commission details of the demand forecasts, data, methodology and assumptions on which the forecasts are based.

2. Prepare a least cost generation plan for the State to meet the 10 years load demand as per the forecast, after examining the economic, technical and environmental aspects of all available alternatives taking into account the existing contracted generation resources and effects of demand side management.

3. Prepare a long term (10 years) plan for the Transmission System compatible with the above load forecast and generation plan ¹[in consultation with CEA. Central Transmission Utility (CTU) shall have to be consulted in connection with systems to evacuate power from Inter-state Transmission System].

4.4 Planning Standards and Procedures:
The Transmission System shall be planned in accordance with the Transmission System planning and security standards under condition 20 of the Licence.

The generation expansion planning shall be carried out in accordance with the power supply planning and security standards under condition 20 of the Licence.

4.5 Planning Responsibility:
4.5.1 The primary responsibility of load forecasting within its area rests with each of the Distribution Companies. The Distribution Companies shall determine peak load and energy forecasts of their respective areas for each category of loads for each of the succeeding ²[5] years and submit the same annually by 31st ³[December] to the Licensee along with details of the demand forecasts, data, methodology and assumptions on which the forecasts are based. The load forecasts shall be made for each of the interconnection points between the Licensee and User and shall include annual peak load and energy projections and daily load curve. The demand forecasts shall be updated annually or whenever major changes are made in the existing forecasts or planning. While indicating requirements of single consumers with large demands (5 MW or higher) the Distribution Company shall satisfy itself as to the degree of certainty of the demand materialising.

4.5.2 The Licensee is responsible for integrating the load forecasts submitted by each of the Distribution Companies and determining the long term (10 years) load forecasts for the State ¹[within 90 days of the date on which the Distribution Companies furnished all the required information consistent to provisions of this Code]. In doing so the Licensee may apply appropriate diversity factors, and satisfy itself regarding probability of materialisation of bulk loads of consumers with demands above 5 MW in consultation with that Distribution Company concerned.

4.5.3 The Licensee may also review the methodology and assumptions used by the Distribution Company in making the load forecast, in consultation with the Distribution Company. The resulting overall load forecast will form the basis of planing for expansion of generation and the Transmission System.

²[4.5.4 In the event, Distribution Companies failed to provide all the requisite information within the time frame and in accordance with the form provided by the Licensee, the Licensee shall approch to the Commission for a directive.]

4.6 Planning Data Requirement:
4.6.1 To enable the Licensee to discharge its responsibilities under the Licence, to conduct System Studies and prepare perspective plans for electricity demand, generation and transmission as detailed in paragraph 4.3 of this Section, the Users shall furnish data to the Licensee from time to time as detailed under Data Registration Section and categorised as Planning Data (PD).

4.6.2 To enable Users to co-ordinate planning, design and operation of their plants and systems with the Transmission System they may seek certain salient data of Transmission system as applicable to them, which the Licensee shall supply from time to time as detailed under Data Registration Section and categorised as Detailed System Data (Transmission).

5.1. Introduction:
Connection Conditions specify the technical, design and operational criteria which must be complied with by any User connected to the Transmission System.

5.2. Objective:
The objective of this Section is to ensure the following:

1. All Users or prospective Users are treated equitably.

2. Any new Connection shall not impose any adverse effects on existing Users, nor shall a new Connection suffer adversely due to existing Users.

3. By specifying minimum design and operational criteria, to assist Users in their requirement to comply with Licence obligations and hence ensure that a system of acceptable quality maintained.

4. The ownership and responsibility for all items of equipment is clearly specified in a schedule (Site Responsibility Schedule) for every site where a Connection is made.

5.3 Site Responsibility Schedule:
For every Connection to the Transmission System for which a Connection Agreement is required, a schedule of equipment shall be prepared by the Licensee with information supplied by the respective Users. This schedule, called a Site responsibility Schedule, shall state the following for each item of equipment installed at the Connection Site:

1. The ownership of equipment.

2. The responsibility for control of equipment.

3. The responsibility for maintenance of equipment.

4. The responsibility for operation of equipment.

5. The manager of the site.

6. The responsibility for all matters relating to safety of persons at site.

An illustrative Site Responsibility Schedule is provided at Appendix A.

5.3.1. The Users owning the connection site shall provide reasonable access and other required facilities to another user whose equipment is installed at the connection site for installation, operation and maintenance etc.

5.4 System Performance:
All equipment connected to the Transmission System shall be of such design and construction as to satisfy at least the requirements of the relevant Indian Standard Specification, where no Standard exists the appropriate IEC Standard or other International Standard will apply.

Installation of all electrical equipment shall comply with IE Rules.

For every new Connection sought, the Licensee shall specify the Connection Point and the voltage to be used, along with the metering and protection requirements as specified in the Metering and Protection Sections.

3[The Transmission System rated frequency shall be 50.00Hz and shall normally be controlled within the limits as per Indian Electricity Rules, 1956 as amended from time to time. The Users shall however be subject to Grid discipline imposed by SLDC as per guidelines mutually agreed in EREB forum.]

⁴[The variation of voltages on the Transmission System may not be more than the voltage range specified in the Indian Electricity Rules, 1956 as amended form time to time.]

Insulation co-ordination of the Users’ equipment shall conform to applicable Indian Standards/Codes. Rupturing capacity of switchgear shall not be less than that notified by the Licensee from time to time.

Protection schemes and Metering schemes shall be as detailed in the Protection & Metering Sections of the Code.

For existing Power Stations, the equipment for data transmission and communications shall be owned and maintained by the Licensee, unless alternative arrangements are mutually agreed.

For new Power Stations the equipment for data transmission and communications shall be owned and maintained by the respective Generator.

5.5. Connection Point:
5.5.1 Generator

Voltage may be 400/220/132 kV or as agreed with the Licensee.

Unless specifically agreed with the Licensee the Connection point shall be the outgoing feeder gantry of Power Station switchyard. Metering point shall be at the outgoing feeder. All the terminal communication, protection and metering equipment owned by the Generator within the perimeter of the Generator’s site shall be maintained by the Generator. Other Users’ equipment shall be maintained by the respective Users. From the outgoing feeder gantry onwards, all electrical equipment shall be maintained by the Licensee.

5.5.2 Distribution Company
Voltage may be 33/11 kV or as agreed with the Licensee.

5.5.3 Eastern Regional Transmission System
For the Eastern Regional Transmission System, the Connection, protection scheme, metering scheme, metering point and the voltage shall be in accordance with the mutual agreement between PowerGrid and the Licensee.

5.5.4. CPPs & Bulk Power Consumers:
Voltage can may be 220/132/33 kv or as agreed with Licensee.

5.6. Data Requirements:
Users shall provide Licensee with data for this Section as specified in the Data Registration Section.

5.7. Procedure for Applications for Connection to and Use of Transmission:
5.7.1 Any User seeking to establish new or modified arrangements for Connection to and/or use of the Transmission System shall submit the following report, data and undertaking along with an application to the Licensee:

5.7.3 The offer shall specify and take into account any works required for the extension or reinforcement of the Transmission System to satisfy the requirements of the Connection application and for obtaining statutory clearances, wayleaves as necessary.

5.7.4 In respect of offers for modification of existing Connection, the terms shall take into account, the existing Connection Agreement.

5.7.5

1. If the nature of complexity of the proposal is such that the prescribed time limit for making the offer is not adequate, the Licensee shall make a preliminary offer within the prescribed time limit indicating the extent of further time required with the consent of the Commission for more detailed examination of the issues.

2. On receipt of the preliminary offer, the User shall indicate promptly whether the Licensee should proceed further to make a final offer within the extended time limit.

5.7.6 All offers (other than preliminary offers) including revised offers shall remain valid for 60 days of issue of offer.

5.7.7 The Licensee shall make a revised offer, upon request by a User, if necessitated by changes in data earlier furnished by the User.

5.7.8 In the event of the offer becoming invalid or not being accepted by any User within the validity period, no further action shall be taken by the Licensee on the Connection applications.

5.7.9 The Licensee may reject any application for Connection to and/or use of Transmission System:

1. If such proposed connections will violate any provisions under Condition 22.4 of the Transmission and Bulk Supply Licence.

2. If the proposed works stated in the application do not lie within the purview of the Licence or do not confirm to any provision of the Grid Code.

3. If the applicant fails to give confirmation and undertakings according to Sub Section 5.7.1 (iii) and 5.7.1 (v) of this Section.

5.8 Connection Agreements:
A Connection Agreement shall include, as appropriate, within its terms and conditions the following:

1. a condition requiring both parties to comply with the Grid Code.

2. details of Connection ¹[technical requirements with specific references to reactive power compensation / operation of Generating Units and Power Station, if any, and commercial arrangements, (in accordance with relevant provision of Indian Electricity Grid Code wherever applicable.;]

3. details of any capital related payments arising from necessary reinforcement or extension of the system.

4. a Site Responsibility Schedule.

   ²[v. general philosophy, guidelines etc. on protection]

5. 9. Appendix:
General format for Site Responsibility Schedule.

APPENDIX - A

SITE RESPONSIBILITY SCHEDULE

Name of Power Station/Sub-Station Site Owner:
Tel. Number:
Fax Number:

6.1. Introduction:
This Section describes the process by which the Licensee carries out the planning of Transmission System Outages, including interface co-ordination with Users.

6.2. Objective:
The objective of this Section is to define the process which will allow the Licensee to optimise transmission Outages with generator and other Users’ Outages while maintaining system security to the extent possible.

6.3. Demand Estimation:
Demand estimation is necessary both in the long time scale to ensure adequate system plant margins and ratings and in the shorter time scale to assist with frequency control (see Schedule and Despatch Section).

Distribution Companies and other agencies involved in bilateral exchanges shall provide to the Licensee their estimates of demand / export for Active Power(MW), Reactive Power(MVAr) and Energy Consumption(MU) at each connection / External Interconnection point for the next financial year by 31^st December of each year on daily / weekly / monthly basis. The Distribution Companies shall intimate to Licensee the methodology used in producing their forecasts.

The Licensee shall use this data  

1. to assist in determination of the generation schedule for next day

   2. to determine the most onerous conditions affecting constraints and voltage performance for next week; 

   3.  to check Outage Plan viability for peak and lean periods for next month. 

The daily / weekly / monthly data shall be in the form of 24 hourly averaged demand figures for each day / each day of week / each day of month.    

The demand / export estimates provided by the Distribution Companies and other agencies involved in bilateral exchanges shall be updated as necessary and sent each month to the Licensee 15 days ahead on same daily / weekly / monthly basis.  

The demand estimates shall be further updated and sent to SLDC in accordance with the provision of Section 7, Scheduling and Despatch. 

The Licensee shall make its own demand forecast using hourly generation summation figures and CPP import / export figures provided under Section 9 or by using suitable computer program, to compare with demand estimates provided by Users.

SLDC shall notify a Contact Person who shall be responsible for day ahead demand forecast. The official and residential telephone numbers of the Contact Person shall be intimated to all the Distribution Companies. Similarly all the Distribution Companies shall notify the Contact Person with telephone numbers and intimate SLDC. In case of change of Contact Person, it should be intimated to SLDC and vice versa.

Distribution Companies shall provide to SLDC estimates of load that may be shed, when required, in discrete blocks with the details of the arrangements of such load sheddings.

All data shall be collected in accordance with procedures agreed between the Licensee and each User.

SLDC shall maintain a database of State demand on an hourly basis.

SLDC shall produce a yearly transmission Outage programme for the next financial year.

All Generators shall provide SLDC with their proposed Outage programmes in writing for the next financial year by 1st August each year.

All Distribution Companies shall provide SLDC with their proposed Outage programmes in writing for the next financial year by 1st August each year.

Outage programmes shall contain identification of unit, Outage start date and duration of Outage.

SLDC shall produce a draft Outage programme based on the information received from Generators and Distribution Companies, taking into account demand estimation and shall carry out studies as required.

SLDC shall inform EREB ⁶[Secretariat of its proposed Outages in writing by 30^th November for each financial year.]

⁷[EREB secretariat will then come out with a draft outage programme for the next financial year by 31^st December of each year for the Regional Grid.]

EREB shall inform SLDC of its proposed Outages that would affect the Transmission System by 1st November each year.

SLDC shall interact with all Users as necessary to review and optimise the draft plan, agree to any changes and produce an acceptable co-ordinated generation and transmission Outage plan by 1st February each year.

SLDC shall release the finally agreed transmission Outage plan, which takes account of Regional and User requirements, to all Users by 1st March each year.

SLDC shall review the final Outage plan quarterly in consultation with ERLDC and Users, who shall be informed by SLDC of any proposed changes.

Users’ requests for additional Outages will be considered by SLDC and accommodated to the extent possible.

SLDC shall inform Users promptly of any changes that affect them.

6.5. Release of Circuits and Generator Units Included in Outage Plan:
Notwithstanding provision in any approved Outage plan, no cross boundary circuits or Generating Unit of a Generator shall be removed from service without specific release from SLDC. This restriction shall not be applicable to individual Generating Unit of a CPP.

Once an Outage has commenced, if any delay in restoration is apprehended, SLDC or User concerned shall inform the other party promptly together with revised estimation of restoration time.

6.6 Data Requirements:
Users shall provide SLDC with data for this Section as specified in the Data Registration Section.

7.1. Introduction:
This Section specifies the procedure to be adopted for the scheduling and despatch of Generating Units to meet demand and Drawal allocation requirements.

It further sets down the procedures to be followed by Users so that the Licensee can meet its daily Drawal Schedule whilst ensuring that Reactive Power drawals/ returns are minimised.

7.2. Objective:
The objective of this Section is to detail the actions and responsibilities of SLDC in preparing and issuing a daily schedule of generation and the responsibilities of Users to supply the necessary data and to comply with that schedule.

This Section details the responsibilities of Users to ensure that SLDC can meet its obligations to follow the daily Drawal Schedule.

All Generators shall provide the hourly MW/MVAr availability (00.00 - 24.00 hours) of all Generating Units, to SLDC on the day ahead basis by 10.00 hours. CPPs ¹[.......] shall provide the hourly import/export figures on the day ahead basis by 10.00 hours.

In working out the MW/MVAr availability, Hydro Power Stations shall take into account their respective reservoir levels and any other restrictions and shall report the same to SLDC.

SLDC shall obtain from ERLDC, capabilities and hourly MW entitlements from ISGS and hourly MW and MWH in the case of Chukha Hydro Power Station, by 11.00 hours on a day ahead basis. SLDC will review it after looking at availability data provided by Generators, export figures from CPPs, the hourly demand estimates from Distribution Companies and any bilateral exchanges.  SLDC will advise ERLDC by 15.00 hours of its Drawal Schedule for each ISGS and Chukha Hydro Power Station, in which the Licensee has shares. In preparation of the schedule, SLDC shall take into account of the relative commercial costs to the Licensee of the operation of Generation units.

SLDC will receive hourly "net Drawal Schedule" in MW from ERLDC  by 17.00 hours for the next day (00.00 hours to 24.00 hours) as summation of the station-wise ex-power plant drawal schedules for all ISGS and Chukha, after deduction of apportioned transmission losses (estimated).

SLDC shall intimate the generation schedule/import schedule for the following day to all Generators / CPPs by 18.00 hours.

Generators shall promptly report to SLDC, changes of Generating Unit availability or capability, or any unexpected situation which could affect its operation. All CPPs shall similarly report regarding their export to the Licensee.

SLDC shall advise Users as soon as possible of any necessary rescheduling.

If Generators or CPPs need to change availability, SLDC to inform ERLDC by 22.00 hours.

SLDC shall receive final Drawal Schedule from ERLDC by 23.00 hours.

SLDC shall prepare the day ahead generation schedule keeping in view the followings:

1. Transmission System constraints from time to time

2. Hourly load requirements as estimated by SLDC

3. The need to provide operating margins and reserves required to be maintained.

4. The availability of generation from Generators, ²[ISGS] and CPPs together with any constraints ³[if any] in each case.

5. Overall economy to Licensee and Customers.

SLDC shall instruct Generators to hold capacity reserves (spinning and/or standby) to the agreed EREB guidelines or as determined for local conditions.

SLDC may also require the Generators/CPPs to generate MVAr within their respective capability limits to hold station bus bar voltages at specified levels.

7.4. Generation Despatch:
All Generators shall regulate generation and CPPs regulate their export according to the daily generation schedule.

All Generating Units, above 5 MW, other than those in a CPP, will be subject to central despatch instructions. CPPs will be subject to these instructions as applicable to their respective exports to the Licensee.

SLDC will despatch by instruction all generation and imports from CPPs according to the hourly day ahead generation schedule, unless rescheduling is required due to unforeseen circumstances.

In absence of any despatch instructions by SLDC, Generators and CPPs shall generate/export according to the day ahead generation schedule.

Despatch instructions shall be in standard format. These instructions will recognise declared availability and other parameters which have been made available by the Generator to SLDC. These instructions shall include time, Power Station, Generating Units (total export in the case of CPP), name of operators sending and receiving the same.

Despatch instructions may include:

1. To switch a Generator into or out of Service.

2. Details of reserve to be carried on a unit.

3. To increase or decrease MVAr generation to assist with voltage ¹[profile]

4. To begin pre-planned Black Start procedures.

5. To hold spinning reserve.

6. To hold Generating Units on standby.

7.5. Communication with Generators:
Despatch instructions shall be issued by E-Mail/telephone, confirmed by exchange of names of operators sending and receiving the same and logging the same at each end. All such oral instructions shall be complied with forthwith and written confirmation shall be issued promptly by Fax, teleprinter or otherwise.

All Generators and CPPs shall comply promptly with a despatch instruction issued by SLDC unless this action would compromise the safety of plant or personnel.

The Generator and CPPs shall promptly inform SLDC in the event of any unforeseen difficulties in carrying out an instruction.

All Generating Units shall have Automatic Voltage Regulator (AVR) in service.

All Generating Units shall have the governor available and in service and must be capable of automatic increase or decrease in output within the normal declared frequency range and within their respective capability limit.

Generators shall immediately inform SLDC by telephone of any loss or change (temporary or otherwise) to the operational capability of any Generating Unit which is synchronised to the system or which is being used to maintain system reserve. Generators shall inform SLDC any removal of AVR and/or governor from service with reasons.

CPPs shall similarly inform any change in status affecting their ability in complying with despatch instructions.

Generators shall not de-synchronise Generating Units, other than in respect of CPPs, without instruction from SLDC except on the grounds of safety to plant or personnel which shall be promptly reported to SLDC.