Using IEC 104

IEC 60870-5-104  is a protocol for power system monitoring and controlling. Mostly used to communicate between substations and control centers over Ethernet (Fiber optics, 2/3/4G, ...). IEC 60870-5-104 protocol is an extension of IEC 60870-5-101 protocol with the changes in transport, network, link and physical layer services to suit the complete network access.

Here you will find basic information about protocol parameters:

• APCI - Application Protocol Control Information
• APDU - Application Protocol Data Unit
• ASDU - Application Service Data Unit

Address

• IP address - every device in Ethernet have physical address
• ASDU address - every slave (client) device has a logical address, also one device could have more than one ASDU address
• IOA  address - information object address

Type identification
Dec	Type	Description	Direction	Support
Process information
1	M_SP_NA_1	Single-point information	Monitor	Yes
2	M_SP_TA_1	Single-point information with time tag	Monitor	Yes
3	M_DP_NA_1	Double-point information	Monitor	Yes
4	M_DP_TA_1	Double-point information with time tag	Monitor	Yes
5	M_ST_NA_1	Step position information	Monitor	No
6	M_ST_TA_1	Step position information with time tag	Monitor	No
7	M_BO_NA_1	Bit string of 32 bit	Monitor	No
8	M_BO_TA_1	Bit string of 32 bit with time tag	Monitor	No
9	M_ME_NA_1	Measured value, normalized value	Monitor	Yes
10	M_ME_TA_1	Measured value, normalized value with time tag	Monitor	Yes
11	M_ME_NB_1	Measured value, scaled value	Monitor	Yes
12	M_ME_TB_1	Measured value, scaled value wit time tag	Monitor	Yes
13	M_ME_NC_1	Measured value, short floating point number	Monitor	Yes
14	M_ME_TC_1	Measured value, short floating point number with time tag	Monitor	Yes
15	M_IT_NA_1	Integrated totals	Monitor	No
16	M_IT_TA_1	Integrated totals with time tag	Monitor	No
17	M_EP_TA_1	Event of protection equipment with time tag	Monitor	No
18	M_EP_TB_1	Packed start events of protection equipment with time tag	Monitor	No
19	M_EP_TC_1	Packed output circuit information of protection equipment with time tag	Monitor	No
20	M_PS_NA_1	Packed single point information with status change detection	Monitor	No
21	M_ME_ND_1	Measured value, normalized value without quality descriptor	Monitor	No
30	M_SP_TB_1	Single-point information with time tag CP56Time2a	Monitor	Yes
31	M_DP_TB_1	Double-point information with time tag CP56Time2a	Monitor	Yes
32	M_ST_TB_1	Step position information with time tag CP56Time2a	Monitor	Yes
33	M_BO_TB_1	Bit string of 32 bit with time tag CP56Time2a	Monitor	No
34	M_ME_TD_1	Measured value, normalized value with time tag CP56Time2a	Monitor	Yes
35	M_ME_TE_1	Measured value, scaled value with time tag CP56Time2a	Monitor	Yes
36	M_ME_TF_1	Measured value, short floating point number with time tag CP56Time2a	Monitor	Yes
37	M_IT_TB_1	Integrated totals with time tag CP56Time2a	Monitor	No
38	M_EP_TD_1	Event of protection equipment with time tag CP56Time2a	Monitor	No
39	M_EP_TE_1	Packed start events of protection equipment with time tag CP56Time2a	Monitor	No
40	M_EP_TF_1	Packed output circuit information of protection equipment with time tag CP56Time2a	Monitor	No
45	C_SC_NA_1	Single command	Control	Yes
46	C_DC_NA_1	Double command	Control	Yes
47	C_RC_NA_1	Regulating step command	Control	No
48	C_SE_NA_1	Set-point Command, normalized value	Control	Yes
49	C_SE_NB_1	Set-point Command, scaled value	Control	Yes
50	C_SE_NC_1	Set-point Command, short floating point number	Control	Yes
51	C_BO_NA_1	Bit string 32 bit command	Control	No
58	C_SC_TA_1	Single command with time tag CP56Time2a	Control	Yes
59	C_DC_TA_1	Double command with time tag CP56Time2a	Control	Yes
60	C_RC_TA_1	Regulating step command with time tag CP56Time2a	Control	No
61	C_SE_TA_1	Measured value, normalized value command with time tag CP56Time2a	Control	Yes
62	C_SE_TB_1	Measured value, scaled value command with time tag CP56Time2a	Control	Yes
63	C_SE_TC_1	Measured value, short floating point number command with time tag CP56Time2a	Control	Yes
64	C_BO_TA_1	Bit string of 32 bit command with time tag CP56Time2a	Control	No
		System information
70	M_EI_NA_1	End of Initialization	Monitor	Yes
100	C_IC_NA_1	Interrogation command	Control	Yes
101	C_CI_NA_1	Counter interrogation command	Control	No
102	C_RD_NA_1	Read command	Control	Yes
103	C_CS_NA_1	Clock synchronization command	Control	Yes
104	C_TS_NA_1	Test command	Control	No
105	C_RP_NA_1	Reset process command	Control	No
106	C_CD_NA_1	Delay acquisition command	Control	No
107	C_TS_TA_1	Test command with time tag CP56Time2a	Control	No
		Parameter
110	P_ME_NA_1	Parameter of measured values, normalized value	Control	No
111	P_ME_NB_1	Parameter of measured values, scaled value	Control	No
112	P_ME_NC_1	Parameter of measured values, short floating point number	Control	No
113	P_AC_NA_1	Parameter activation	Control	No
		File transfer
120	F_FR_NA_1	File ready	File transfer	No
121	F_SR_NA_1	Section ready	File transfer	No
122	F_SC_NA_1	Call directory, select file, call file, call section	File transfer	No
123	F_LS_NA_1	Last section, last segment	File transfer	No
124	F_FA_NA_1	ACK file, ACK section	File transfer	No
125	F_SG_NA_1	Segment	File transfer	No
126	F_DR_TA_1	Directory	File transfer	No
127	F_SC_NB_1	Request archive file	File transfer	No

Cause of transmission
Dec	Description
1	Periodic, cyclic
2	Background interrogation
3	Spontaneous
4	Initialized
5	Interrogation or interrogated
6	Activation
7	Confirmation activation
8	Deactivation
9	Confirmation deactivation
10	Termination activation
11	Return information caused by a remote command
12	Return information caused by a local command
13	File transfer
20	Interrogated by general interrogation
21	Interrogated by interrogation group 1
22	Interrogated by interrogation group 2
23	Interrogated by interrogation group 3
24	Interrogated by interrogation group 4
25	Interrogated by interrogation group 5
26	Interrogated by interrogation group 6
27	Interrogated by interrogation group 7
28	Interrogated by interrogation group 8
29	Interrogated by interrogation group 9
30	Interrogated by interrogation group 10
31	Interrogated by interrogation group 11
32	Interrogated by interrogation group 12
33	Interrogated by interrogation group 13
34	Interrogated by interrogation group 14
35	Interrogated by interrogation group 15
36	Interrogated by interrogation group 16
37	Interrogated by counter general interrogation
38	Interrogated by interrogation counter group 1
39	Interrogated by interrogation counter group 2
40	Interrogated by interrogation counter group 3
41	Interrogated by interrogation counter group 4
44	Type Identification unknown
45	Cause unknown
46	ASDU address unknown
47	Information object address unknown

Block Information

• By adding IEC104 slave block , IEC 104 will be activated on the RTU.
• TCP or Serialport block is connected to IEC104 block ser input.
• IEC 104 blocks must be added for each server to serve multiple servers.
• Asd input is used if IEC104 Asdu address is set from outside but not inside block.
• On the rising edge of the trigger, periodic transmission between IEC104 objects is activated and the selected objects are transmitted to the server periodically. Trigger input can be left blank.

Ser: TCP Socket Input. The TCP server socket block from which the IEC104 protocol will work is connected from this input

Trg: Trigger Input Trigger input for periodic sending. It works as a rising edge.

Asd: Asdu Address Input The ASDU address is used as input.

Q1: Link Status If the IEC104 connection between SCADA and RTU is installed, this output value is 1, otherwise 0.

Q2: SCADA write status, If SCADA requests select and execute, a pulse is generated at this output.

Custom Settings

* AsduAddress: IEC104 slave station ASDU address is defined

AsduAddress: IEC104 slave station ASDU address is defined

T0: Timeout for the establishment of the connection with the server. (Not used Slave)

T1: This parameter defines the time in seconds that slave waits maximum for an acknowledge from the master.

T2: Timeout period for Ack (A S-format frame  will be sent at the latest after this time starting from the last received telegram from the master)

T3: Test frame sending time (A Test frame will be sent at the latest after this time starting from the last received telegram from the master)

K: The maximum allowable difference between the sequence number in the received packet and the number in the send status variable.

W: ACK(acknowledge message) sending frequency(sends ACK after W packets)

Sample Application

In RTU logic projects , with the addition of IEC 104 Slave Block, the IEC 104 protocol is activated in the RTU. Variables in the RTU logic project, IEC104 association is provided in the variable address table.

Variable Mapping with Protocol

Variable Address Table

The relevant protocol is activated in the RTU logic project by adding the protocol block. Variables in the RTU logic Project, association between protocol.is provided in te variable address table

Defining Line Labels

Line label can be defined for all blocks defined on the Mikrodiagram. In the variable table, the line label must be defined in order to be able to associate with the protocol addresses.

Attaching a Line Label

Alias: A special name is given that defines this defined variable.

Start Address:The address allocated for this variable on SCADA is written here. It is written as a decimal value

Line Label:The block to be associated on the Mikrodiagram is selected with the line label.

Point Count:Calculated automatically. It makes sense on tables.

Protocol Type:Modbus, Dnp3, IEC101, IEC104 are selected. Object type will change according to protocol type.

Object Type:IEC104 object type information selected. look the protocol type information for detailed information.

Object Class:The class information to which the variable belongs is selected.

Send On Trigger:IEC104 Slave block is the selection to send to this SCADA as a periodic send when the test is detected from the trigger input.

Send Method:
If the value of the defined variable is changed, the operation to be performed is selected.
Level: When the quantity defined in "Change Value" is changed, the transmission is triggered.
Percentage: The transmission is triggered when there is a change in the percentage defined in "Change Value".
None: Value exchange does not trigger posting

Change Value: With the "Send method", it adjusts the percentage change in the level.