NEPOOL OPERATING PROCEDURE No.7

ACTION IN AN EMERGENCY

APPROVED:	July 8, 1998 by the NEPOOL Regional Market Operations Committee and July 23, 1998 by the NEPOOL Regional Transmission Operations Committee to be implemented for the Second Effective Date for Market Implementation

REFERENCE:  1.	NPCC Emergency Operation Criteria A3
	2.	NERC Policy 5 ‑ Emergency Operations
3.	NEPOOL Operating Procedure No.19 - Transmission Operations
4.	NEPOOL Operating Procedure No. 4 - Action During a Capacity 				Deficiency
5.	NEPOOL Operating Procedure No. 6 - System Restoration
6.	NEPOOL Operating Procedure No. 12 - Voltage and Reactive Control

SATELLITE INSTRUCTION NO.

CONVEX:			Operating Instruction No.7

MAINE:			MAINE Operating Procedure No.7

NEW HAMPSHIRE:		NHSOP #7 Action In An Emergency

REMVEC II:			Operating Procedure No.7 – Action During An Emergency

Table of Contents

PART I – INTRODUCTION								        3

PART II – RESPONSIBILITY							        3

PART III – PROCEDURE								        4
I.	Preparation For Implementation	4
II.	Procedures for Low Frequency Conditions	4
III.	Procedures for a Transmission Emergency	6
IV.	Procedures for Unacceptable Voltage Conditions	6
V.	Restoration of Load	6

Appendix A – Automatic Load Shedding Schedule
Appendix B – Manual Load Shedding Schedule
Appendix C – Instructions for Implementation of Manual Load Shedding

PART I - INTRODUCTION

This document establishes procedures to be followed in the event of an operating emergency involving unusually low frequency, equipment overload or unacceptable voltage levels in an isolated or widespread area of New England.  The objectives in establishing these emergency procedures are:

1.	To minimize the effect on customer service.

2.	To restore the balance between customers' load and available generation in the shortest practicable time.

3.	To minimize the risk of damage to transmission and generating equipment, to distribution equipment and to customers' equipment.

PART II - RESPONSIBILITY

I.	ISO New England Responsibility

The ISO has the responsibility and authority to direct the actions that may be required for the implementation of this procedure, such as load shedding or opening of circuits, when the emergency situation involves:

A.	An overall capacity deficiency in New England or in any area within New England.

B.	New England's interconnections with adjacent Control Areas/systems.

C.	Conditions on facilities external to New England caused by operations or conditions 	within the New England Control Area.

D.	Transmission and/or generating facilities within New England.

II.	Satellite Responsibility

The Satellites have the responsibility and authority to direct the actions that may be required for the implementation of this procedure when the emergency condition involves:

A.	A capacity deficiency in an area wholly within one Satellite.

B.	The transmission and/or generating facilities under the operating jurisdiction of a single Satellite.

C.	The risk of damage to equipment under the operating jurisdiction of a single Satellite when accompanied by a loss of communications with the ISO.

PART III - PROCEDURE

I.	Preparation For Implementation

Normally, the potential need for emergency actions prescribed by this procedure should be determined well in advance of the time the actions must be implemented.  This procedure may be implemented either before, during, or after action taken under NEPOOL OPERATING PROCEDURE No. 4 ‑ Action During A Capacity Deficiency (OP 4) depending on the circumstances of the emergency.  However, OP 4 will normally precede implementation of this procedure.

When system conditions indicate that implementation of this procedure may be required, the ISO and the Satellites will establish and, if appropriate, maintain continuous communication in preparation for an ISO directive to implement the procedure.  Prompt action may provide time to be more selective in the application of this procedure.

If any Satellite and the ISO are unable to establish prompt  communication, the Satellite will proceed to implement the procedure independently.

When time and circumstances allow, the ISO and the Satellites shall discuss the emergency conditions and reach consensus on the actions to be taken and the timing of those actions.

When operating circumstances do not allow time for consensus decisions, the ISO and/or the Satellite will initiate the necessary actions prescribed by this procedure with the understanding that actions resulting in the higher level of reliability will be taken.

II.	Procedures for Low Frequency Conditions

In an emergency characterized by a frequency drop, identification of the deficient Area or Areas is vital to expedite corrective action.  The ISO Control Room Staff shall establish communications with other interconnected Areas, as follows, to determine, if possible, the cause of the frequency decline and the action required to restore frequency to 60.00 Hz.

A.	When the cause of the declining frequency is outside of New England: 

•	Confirm existing interchange schedules with adjacent NPCC Areas.

•	Regulate the New England ties to maintain the frequency‑biased interchange schedules.

•	Increase the amount of synchronized reserve to be able to adjust the interchange schedule further, if needed.
•	Make known to external Areas the amount of emergency capacity NEPOOL can make available.
•	Actions described in Section B below may be implemented when external Areas request assistance from the ISO.  Please note that some of these actions will occur automatically regardless of the Area causing the frequency decline. 

B.	When the cause of the declining frequency is due to a deficiency in New England:

•	Confirm existing interchange schedules with adjacent NPCC Areas.

•	Request assistance from external Areas up to the emergency transfer limit of the interconnection tie lines.

When the frequency reaches 59.90 Hz:

•	Disconnect any pumped storage units operating in the pumping mode.  They will be automatically disconnected at 59.65 Hz.

•	Order fast‑start non-synchronized units into service as required.

When the frequency reaches 59.80 Hz:

•	Automatic Generation Control (AGC) will be tripped automatically

•	Direct all thermal generation to their High Operating Limits (HOL) at maximum response rates.

When the frequency reaches 59.30 Hz:

•	Underfrequency relays will provide 10% load relief.  By the time the frequency reaches 59.00 Hz, confirm that this relief was provided (Appendix A, Emergency Condition A).

When the frequency reaches 58.80 Hz:

•	Underfrequency relays will provide an additional 15% load relief.  By the time frequency reaches 58.50 Hz, confirm that this relief was provided. (Appendix A, Emergency Condition B)

If the load shedding by automatic underfrequency relays does not stabilize the frequency and it continues to decline below 58.50 Hz

•	Order manual load shedding in accord with Appendix B to the extent necessary to restore frequency to 60.00 Hz
•	50% of New England's load, including the 25% that is shed automatically, can be shed manually.  Details of the manual load shedding procedure and statements to be used by operators are included in Appendix C.

•	All stations shall take the necessary action, including separating units from the system, to preserve generation and minimize damage and service interruptions.

III.	Procedures for a Transmission Emergency

Operation of the transmission system under emergency conditions shall be governed by NEPOOL OPERATING PROCEDURE No. 19 ‑ Transmission Operations (OP 19).  Emergency Actions, including the switching of transmission elements, implementing voltage reductions, and the shedding of firm load, can be taken by the ISO and the Satellites to maintain reliability.

The ISO and Satellite operators are responsible to keep appropriate Supervisors at the ISO and the Satellites advised as to conditions that might necessitate management review of the need to implement Emergency Actions on a pre‑contingency basis.

IV.	Procedures for Unacceptable Voltage Conditions

NEPOOL OPERATING PROCEDURE No. 12 ‑ Voltage and Reactive Control (OP 12) and various voltage guides define criteria and establish guides for action to be taken to insure that desirable levels of voltage are maintained on the transmission system.  The Satellite Control Center shall make every effort to correct unacceptable voltage and shall coordinate actions with the ISO.

When unacceptable voltage conditions occur and corrective actions described in NEPOOL OP 12 and/or the voltage guides are not effective, the ISO Control Room Staff and/or the Satellite operators should take Emergency Actions, as defined in NEPOOL OP 19, to correct the situation.

The ISO Control Room Staff and Satellite operators are responsible to keep appropriate Supervisors at the ISO and the Satellites advised as to conditions that might necessitate management review of the need to implement Emergency Actions on a pre‑contingency basis.

V.	Restoration of Load

The ISO will direct the restoration of any load shed under this procedure when system conditions permit.

Document History

OP7
8/18/98
Appendix A

	AUTOMATIC - LOAD SHEDDING SCHEDULE
	BASED ON A NEW ENGLAND PEAK LOAD OF 21,400 MEGAWATTS

 		  EMERGENCY  PERCENT LOAD   APPROX. MW OF
SYSTEM		PEAK LOAD*  CONDITION  TO BE SHED	  LOAD TO BE SHED

NEPOOL		21,400 MW		 A		  10			  2,140
 B		  15			  3,210

CONVEX		 7,050 MW		 A		  10			    705
 B		  15			  1,058

MAINE		 1,500 MW		 A		  10			    150
 B		  15			    225

NEW HAMPSHIRE	 1,300 MW		 A		  10			    130
 B		  15			    195

REMVEC II		11,550 MW		 A		  10			  1,155
 B		  15			  1,732

Note:	Each Satellite and Participant is expected to establish 
		automatic load shedding procedures based on peak-load
		percentages which will result in approximately the figures
		shown for each Satellite.  It is understood that figures
		can vary from Participant to Participant.

		*  Values rounded to the nearest 50 MW.

OP7 APPA.
4/27/98

	APPENDIX B
	MANUAL LOAD SHEDDING SCHEDULE
	BASED ON A NEW ENGLAND PEAK LOAD OF 21,400 MEGAWATTS
	STEP NO. AND APPROXIMATE MEGAWATTS OF LOAD TO BE SHED

																		     NEW
			  New England     CONVEX	    MAINE    	HAMPSHIRE  	  REMVEC		 New England
	  	STEP#      21,400 MW 	  	7,050 MW    1,500 MW    1,300 MW     11,550 MW    21,400 MW 		 STEP#

		  	1				214		   	70				15				13				116			  	214	 	 		1
  	  		2				428			  140			   30		  		26	 			232		  		428		 	 	2
  			3		   	642		     210			   45		  		39	  			348		  		642		  		3
  			4		   	856		     280		   	60		  		52	  			464		  		856		  		4
  			5		 	 1,070		     350		   	75		  		65	  			580			 1,070		  		5
  			6		 	 1,284		     420		   	90		  		78	  			696			 1,284		  		6
  			7		 	 1,498		     490		  	  105		  		91	  			812			 1,498		  		7
  			8		 	 1,712		     560		  	  120	     	  104		  		928			 1,712		  		8
  			9		 	 1,926		     630		  	  135	     	  117	    	 1,044			 1,926		  		9
 	  	  10		 	 2,140		     700		  	  150	     	  130	    	 1,160			 2,140		     10
 	  	  15		 	 3,210		  	1,050		  	  225	     	  195	    	 1,740			 3,210		     15
 	  	  20		 	 4,280	      1,400		  	  300	     	  260	    	 2,320			 4,280		     20
 	  	  25		 	 5,350	      1,750		  	  375	        325	    	 2,900			 5,350		     25
 	  	  30		 	 6,420	      2,100		  	  450	     	  390	    	 3,480			 6,420		     30
 	 	  35		 	 7,490	      2,450		  	  525	     	  455	    	 4,060			 7,490		     35
 	  	  40		 	 8,560	      2,800		  	  600	     	  520	    	 4,640			 8,560		     40
 	  	  45		 	 9,630	      3,150 		  675	     	  585	   	 5,220			 9,630		     45
 	  	  50			10,700	      3,500		  	  750	     	  650	   	 5,800	     	10,700		     50

Note:	Each Participant is expected to develop a manual load shedding plan which will result in shedding 50% of load on
		peak.  The step numbers shown in this table correspond to an equivalent percent and assume all Satellites peak
		coincidentally with NEW ENGLAND, which may or may not be true.  Insofar as Satellite and Participant loads conform to
		the NEW ENGLAND load, an "X" percent load change in NEW ENGLAND will result in the same percent change for the Satellite or Participant.  Clearly, all loads do not conform to the NEW ENGLAND loads.  Therefore, the table is approximate only.
 OP 7 APPB.
4/27/98
APPENDIX C

INSTRUCTIONS FOR IMPLEMENTATION OF
MANUAL LOAD SHEDDING

The following instructions are to be observed by the ISO Control Room Staff during the manual shedding of load.  These instructions are to be used in conjunction with Appendix B which specifies the step number of the load shedding procedure.

I.	WHEN SHEDDING LOAD NEW ENGLAND WIDE:

A.	Communication With Satellites

All Satellites will be on the party line prior to the time the ISO Control Room Staff issues instructions.

B.	Quantity of Load

The ISO Control Room Staff will direct the quantity of load to be shed or restored by specifying a step number.

Step Number =Total MW Load to be Shed or Restored x 100
                        		Instantaneous New England Load

C.	Instruction Messages

The ISO Control Room Staff will issue concise verbal instructions and await Satellite acknowledgment, which should be received from all Satellites alphabetically. Typical messages are as follows:

Implementation:

a.	ISO TO ALL:	Implement OP 7 ‑ Manually shed load from step ____ through step _____.

b.	ISO TO ALL:	Implement OP 7 ‑ Manually restore load from step ____ through step _____.

Acknowledgment by Satellite:

a.	_____, OP 7 	Manually shed load from step _____through step _____.

b.	_____, OP 7 ‑	Manually restore load from step _____ through step _____.

D.	Examples:  Typical Implementation and Acknowledgment Messages

1.	a.	New England Load ‑ 21,400 MW
b.	NEED ‑ Shed 500 MW uniformly throughout New England.
c.	Messages:
Implementation:   50,000 / 21,400 = 2.3
NOTE:  To achieve 500 MW within Appendix B load shedding schedule, the fractional step result must be rounded down or up to the next step value.

                    ISO TO ALL:	Implement OP 7 ‑ Manually shed load from step 1 through step3

          			Acknowledgment by Satellite:

                    CONVEX:	OP 7 ‑ Manually shed load from step 1 through step 3
                    MAINE:	OP 7 ‑ Manually shed load from step 1 through step 3
                    N.H.:		OP 7 ‑ Manually shed load from step 1 through step 3
                    REMVEC II:	OP 7 ‑ Manually shed load from step 1 through step 3

2.	a.	New England Load = 20,900 MW
b.	NEED: Restore 500 MW of load that had been previously shed uniformly throughout New England.
c.	Messages:
                    Implementation:	50,000 / 20,900 = 2.4

NOTE:  To achieve 500 MW within Appendix B load-shedding schedule, the fractional step result must be rounded down or up to the next step value.

                    ISO TO ALL:	Implement OP 7 ‑ Manually restore load from step 3 through step 1
                    
Acknowledgment by Satellite:
                    CONVEX:	OP 7 ‑ Manually restore load from step 3 through step 1
                (Other Satellites respond in alphabetical order)

II.	WHEN SHEDDING LOAD IN INDIVIDUAL SATELLITE(S)

A.	Communication With Satellite(s)

The affected Satellite(s) will be contacted individually and instructions will be issued by the ISO Control Room Staff.  The unaffected Satellites will then be contacted individually and informed of the situation.

B.	Quantity of Load

The ISO Control Room Staff will direct the quantity of load to be shed or restored by specifying a (MW) amount.  The Satellite Operator will then be responsible for converting the MW amount into a step number if required. 

NOTE:	Applicable Satellites are those within the area in which load shedding will be effective in alleviating a problem.

C.	Instruction Messages

The ISO Control Room Staff will issue concise verbal instructions and await Satellite acknowledgment. Typical messages are as follows:

Implementation:

a.	ISO TO ___:	Implement OP 7 ‑ Manually shed (  ) MW of load. 

b.	ISO TO ___:	Implement OP 7 ‑ Manually restore  (  ) MW of load. 

Acknowledgment by Satellite:

a.	_____, OP 7 ‑ Manually shed (  ) MW of load. 
b.	_____, OP 7 ‑ Manually restore (  ) MW of load. 

D.	Examples: Typical Implementation and Acknowledgment Messages

1.	a.	NEED ‑ Shed 200 MW of load in CONVEX.
b.	Messages

                    ISO TO CONVEX: Implement OP 7 ‑ Manually shed/restore (200) MW of load.
							  
                    Acknowledgment by Satellite:

				CONVEX:	OP 7 ‑ Manually shed/restore (200) MW of load.

E.	Notification Messages

Unaffected Satellites will be notified by the ISO Control Room Staff after specific Satellites have been instructed to implement OP 7.  A typical notification and message for the ISO Control Room Staff and System Operators is:

          Implementation:

               ISO To (Unaffected Satellites)

This is a notification that OP 7 is being implemented in CONVEX.  CONVEX has been instructed to manually shed/restore (  ) MW load. 

               Acknowledgment by Satellite:

               (Unaffected Satellites),	OP 7 notification.
			Unaffected Satellites acknowledge that
			CONVEX manually shed/restored (  ) MW of load. 

OP7 APPC.
8/18/98