BMU

Balancing Mechanism Unit

BOA

Bid Offer Acceptance

EDL

Electronic Dispatch Logging – A message transfer mechanism

MEL

Maximum Export Limit

MIL

Maximum Import Limit

MNZT

Minimum Non-Zero Time

MZT

Minimum Zero Time

NDZ

Notice to Deviate from Zero

NETA

New Electricity Trading Arrangements

NTB

Notice to Deliver Bids

NTO

Notice to Deliver Offers

RDR

Run-down Rates

RUR

Run-up Rates

SEL

Stable Export Limit

SIL

Stable Import Limit

Destination

1

6

Name of Control Point

Terminator

7

1

Part terminator character "^"

Destination

1

6

Name of Control Point

Time-Stamp

8

23

Time message received from Wide-area Network. Obtained from local node system clock.

Terminator

31

1

Part terminator character "^"

Time-Stamp

1

23

Time message received from Wide-area Network. Obtained from local node system clock.

Terminator

24

1

Part terminator character "^"

Category

1

1

The category of message. Instruction, Submission etc. See Table 5

Type

2

1

The type of the message. This field carries the dialogue between Communication Layers.

See Table 6 for details.

Instruction Type

3

1

NOTE: This field is only used for Instruction Category Messages and is a space for all other Categories of message

See Table 7 for Details.

Error

4

1

Flag set to space by originating process. The message may be returned with the flag set. See 0 for details.

Terminator

5

1

Part terminator character "^"

C

Control Messages. See Table 9 for Data Part details

I

Instruction Messages. See Table 12, Table 13, Table 14, Table 15 and Table 16 for Data Part details

R

Submission Messages. See Table 18 for Data Part Details

N

New

Send

A new (real-time) message.

W

Waiting

Return

The remote Communications Layer has received & validated the referenced message. It is now waiting for manual action. This type is often called Technical Acknowledgement in earlier papers.

U

User Acknowledgements

Return

The remote operator has seen the referenced message.

A

Acceptance

Return

The remote operator accepts the referenced message.

R

Reject

Return

The remote operator rejects the referenced message.

T

Telephoned

Send

Upon re-connection of systems, messages that have been transmitted by telephone are sent electronically to allow the systems to reconcile themselves.

D

Dispute

Return

The remote system cannot reconcile a manually entered transaction.

Space

Control Message, Submission Message, or EDL closed instruction messages.

See Table 9, Table 12, Table 13, Table 14 and Table 18 for Data Part details

V

EDL Voltage Control Instruction.

See Table 15 for Data Part details.

P

Pumped Storage Message. See Table 16 for details

Space

Original message

E

An error is detected in a received message. Either the original message is returned to the originator with a four-character error code appended to it or a new message identifying the reference number of the original message together with a 4-character error code is sent to the originator. The error code may relate to the syntax or data consistency of the message

X

A message is returned to the originator. The message was valid and data consistent when first received, but while waiting for a user acknowledgement, other parameters have changed and the message is no longer consistent. It is thus flagged as expired i.e. a valid message that is no longer meaningful.

Name

1

9

Control Point Name (VERSON message only) or BM Unit Name

All

Ref Number

11

10

Message Reference Number

All

Log Time

22

17

Time message logged by originating process

All

Type

40

6

Specifies the type of control message and the structure of the type dependent message part.

N

Type dependant

Type

Details

VERSON

See Table 11

SELECT

The Control Point is selected by the NETSO for EDL.

DESEL

The Control Point is de-selected by the NETSO for EDL

PATH

There is a path from the Control Point Communication Layer to the BM Unit operator.

NOPATH

There is NO path from the station Communication Layer to the BM Unit operator

Error Code

40, 47 or 52

4

See Table 10 for meaning

Any

E

Terminator

44, 39, 46, 51, or 56

1

Part terminator character "^"

All

C001

Invalid Control Point/BM Unit ID

C002

Invalid Control Type

C003

Unsupported Version Number

C004

Message arrived before VERSION accept

Type

40

6

VERSON

Version

47

4

Latest Supported EDL Interface Definition.

The field is a formatted numeric value. e.g. 0021 to specify version 2.1. The version number is changeable and reflects the current level of messages supported at the NETSO and the Control Point.

Name

1

9

BM Unit Name

All

Ref Number

11

10

Instruction Reference Number

All

Log Time

22

17

Time message logged by originating process

All

Start Instruction Code

40

5

This may be one of the following codes SYN, HTS or the numeric value 0.

N, T

Start Reserve

46

3

Not used.

N, T

Start Time

50

17

Start time of the instruction.

N, T

Reason Code

68

3

Three character reason code applied to steam plant; the first character explains why the instruction was issued, the second character indicates whether the BM Unit is in frequency response mode.

N,T

Target Instruction Code

72

5

This may be one of the following codes OFF, HTS, CHS or the numeric value 0.

N, T

Target Reserve

78

3

Not used.

N, T

Target Time

82

17

Target time of the instruction.

N, T

Error Code

40, 100

4

See Table 17 for meaning

Any

E, X

Terminator

39, 44, 99 or 104

1

Part terminator character "^"

All

Name

1

9

BM Unit Name

All

Ref Number

11

10

Instruction Reference Number

All

Log Time

22

17

Time message logged by originating process

All

Type

40

4

Type of instruction. BOAI or DEEM.

N, T

BOA Number

45

10

BM Unit Bid/Offer Acceptance Number

N, T

Number of Data Points

56

2

Count of the number of MW / Time pairs that make up this closed instruction. There must be a minimum of 2 pairs and a maximum of 5.

N, T

MW₁

59

5

MW Value 1

±nnnn

N,T

T₁

65

17

Time value 1

MW₂

83

5

MW Value 2

Error code A

N, T

T₂

89

17

Time value 2

MW₃

107

5

MW Value 3

Optional MW / Time pair 3;

Error code B

N, T

T₃

113

17

Time value 3

MW₄

131

5

MW Value 4

Optional MW / Time pair 4;

Error code C

N, T

T₄

137

17

Time value 4

MW₅

155

5

MW Value 5

Optional MW / Time pair 5;

Error code D

N, T

T₅

161

17

Time value 5

Error Code

40,

107 A,

131 B,

155 C,

179 D

4

See Table 17 for meaning

Any

E, X

Terminator

39, 44,

106, 111,

130, 135,

154, 159

178, 183

1

Part terminator character "^"

All

Name

1

9

BM Unit Name

All

Ref Number

11

10

Instruction Reference Number

All

Log Time

22

17

Time message logged by originating process

All

Type

40

4

Type of instruction. REAS

N, T

Reason Code

45

3

Three character reason code.

N, T

Start Time

49

17

Start time of the instruction.

N, T

Error Code

40, 67

4

See Table 17 for meaning

Any

E, X

Terminator

39, 44, 66 or 71

1

Part terminator character "^"

All

Name

1

9

BM Unit Name

All

Ref Number

11

10

Instruction Reference Number

All

Log Time

22

17

Time message logged by originating process

All

Type

40

4

Type of instruction. MVAR or

VOLT

N, T

Value

45

4

Target value as a whole number preceded by minus ("-" = negative value), plus ("+" = positive value), or space (" " = positive value) and with 3 digits (i.e. leading zero's always supplied).

Note: + zero & - zero are treated as same instruction

N, T

Target Time

50

17

Target time of the MVAR or VOLT instruction.

N, T

Error Code

40, 68

4

See Table 17 for meaning

Any

E, X

Terminator

39, 44, 67 or 72

1

Part terminator character "^"

All

Name

1

9

Pumped Storage Unit Name

All

Ref Number

11

10

Instruction Reference Number

All

Log Time

22

17

Time message logged by originating process

All

Reason Code

40

4

Four character reason code, (see below for more detail)

N, T

Start Time

45

17

Start time of instruction.

N, T

Target

63

5

Depending on the reason code: a mnemonic or a real value (see below for more detail).

N, T

Target Time

69

17

Target time of the instruction.

N, T

Error Code

87

4

See Table 17 for meaning

Any

E, X

Terminator

92

1

Part terminator character "^"

All

LFSM

Limited Frequency Sensitive Mode

PSHF

Carry Primary, Secondary and High Frequency Response

EMRG

Emergency instruction (instruction to operate outside declared parameters)

FRES

Fast Response Required

LFRY

Instruction to set an Low Frequency relay

DROP

Droop instruction

BKDN

Breakdown

MW

Reason code to be applied to the Pumped Storage BOA Closed Instruction

SH

Shutdown

SG

Spin Gen

SP

Spin Pump

Nn.nn

Set low frequency relay to nn.nn Hz. For example nn.nn could be 49.85. Where nn.nn is sent as 00.00 this should be interpreted as >remove LF relay setting.

n.n

Set droop to n.n %

LFSM

x

x

x

x

x

PSHF

x

x

EMRG

x

x

x

x

x

FRES

x

LFRY

x

DROP

x

BKDN

x

I001

Invalid BM Unit ID

I002

Invalid Reference Number (Current reference  Last reference, or no previous reference to instruction with this number)

I003

General instruction syntax error (instruction parsing failed)

I004

Instruction received for a BM Unit with NO PATH

I005

Instruction received before Version Control Procedure completed

I006

Telephoned Instruction received with an Invalid Reference Number.

I007

Attempt to recover previously rejected instruction

I008

Unable to log instruction

I009

Invalid Telegraph Instruction Number

I010

Attempt to Reject Reconciliation Instruction which has already been sent to Settlements

Name

1

9

BM Unit Name

All

Ref Number

11

10

Submission Reference Number

All

Log Time

22

17

Time message logged by originating process

All

Type

40

6

Specifies the type of Submission and the structure of the type dependent message part.

N, T

Type

Dependent

47

Max 57

Type

Details

N, T

MEL, MIL

(error code A)

Table 19

RURE, RURI,

RDRE, RDRI

(error code B)

Table 20

NDZ, NTO, NTB, MZT, MNZT

(error code C)

Table 21

SEL, SIL

(error code D)

Table 22

MDVP

(error code E)

Table 23

Error Code

40 any,

103 (A),

79 (B),

51 (C),

57 (D),

61 (E)

4

Not used.

Any

E, X

Terminator

39, 44

102, 107,

78, 83,

50, 55,

56, 61,

60, 65

1

Part terminator character "^"

All

Type

40

6

“MEL” or “MIL” keyword

Time from

47

17

Start time

MW from

65

9

MW at time from (±nnnnnnnn)

Time to

75

17

End time

MW to

93

9

MW at time to (±nnnnnnnn)

Type

40

6

“NDZ”, “NTO”, “NTB”, “MZT” or “MNZT keyword

Time value

47

3

Number of minutes

Type

40

6

“SEL” or “SIL” keyword

Value

47

9

MW level

Type

40

6

“MDVP” keyword

MDV

47

11

Max Delivery Volume (MW hours)

MDP

59

3

Max. Delivery Period (minutes)

R001

Invalid syntax

R002

Invalid BM Unit

R003

Value out of bounds

R004

Invalid run rate break point

R005

Invalid run rate

R006

Invalid combination of run rates/breakpoints

R007

Invalid run rate breakpoint; breakpoints not monotonically increasing

R008

FROM time does not predate TO time

R009

Invalid FROM time

R010

Invalid TO time

R011

FROM time must be equal to or after SUBMISSION time

R999

Contact the NETSO

Code

1

3

See 0

Time Stamp

5

23

Time alarm raised by Server Layer, obtained from local node system clock.

IC

Input channel connected

OC

Output channel connected

ID

Input channel disconnected

OD

Output channel disconnected

NX

Network Partner Exited

Destination

1

6

Name of BM Unit

Code

8

6

See 0

Time Stamp

15

23

Time alarm raised by Server Layer, obtained from local node system clock.

C-P

Primary Channel Connected

C-S

Secondary Channel Connected

D-P

Primary Channel Disconnected

D-P(R)

Primary Channel disconnected due to a link re-configuration

D-S(R)

Secondary Channel disconnected due to a link re-configuration

D-P(U)

Primary Channel disconnected due to a message being undelivered/unacknowledged

D-S(U)

Secondary Channel disconnected due to a message being undelivered/unacknowledged

D-S

Secondary Channel Disconnected

NX

Network Partner Exited