Now you need to configure measurements: currents, voltages, open delta voltage. It is necessary to create first program configuration in project‘s configuration tree foremost. In this article I describe how to draw function blocks, how to connect to them PLC‘s physical channels: currents and voltages; how to declare variables, how to choose variables‘ types. In article no.5 „Creating project’s configuration tree with CAP505“ you can read how to create project configuration tree. In article no.6 „Setting analogues channels of CAP505” you can learn how to set analogue measurements channels. About PLC REF54x configuration read in ABB manual ”Protection & Control Terminals REF 54_, REM 54_, RET 54_, REC 523 Configuration Guideline 1MRS750745-MUM”. More about function blocks you can explore in manufacturer’s ABB manuals:
„Technical Descriptions of Functions: Introduction 1MRS750528-MUM“
„MECU3_ Three-Phase Current Measurement 1MRS752340-MUM“
„MEVO3_ Three-Phase Voltage Measurement 1MRS752345-MUM“
„MEVO1_ Residual Voltage Measurement 1MRS752344-MUM“

1. Run „Relay Configuration Tool“:

7.1

2. In project‘s configuration tree select program unit „Measure“ and open it:

7.2

Window „Graphic:Measure“ is empty:

7.3

In „Graphic: Measure“ window you can draw function blocks, insert new variables, make connections between function blocks.

Function block – this is FBD programming language‘s element, which can have various functions (measure, signalize, control, react). Types of function blocks‘:
• Logical
• Protection
• Measurement
• Signalization
• Others

Logical function blocks are logical AND, OR, inverters and others for example. These logical blocks execute logical operations with variables of „boolean“ types. These variables can assert two states: logical „0“ or logical “1“. More about logical blocks you can read in manufacturer’s ABB manual “Technical Descriptions of Functions Introduction 1MRS750528-MUM“.

Function blocks of protection are used to protect power network, for example from overcurrents, under/overvoltges, under/over frequencies and others. NOC3low function block (non-directional overcurrent 3-phase protection low stage) is used to realize overcurrent protection with time inverse characteristic.

Function blocks of signalization are used to link various start, trip signals (variables) to PLC‘s LEDs.
PLC REF543 has 9 LEDs, which visualize protections, failures, external circuits tripping:

 

7.4

LEDs (9 units) in figure are left from human machine interface (HMI).

 

Function blocks of measurements measure currents, voltages, frequency, powers and visualize them on HMI. In this article I describe measurements function blocks such as MECU3A (currents measurements), MEVO3A (voltage measurements) and MEVO1A (open delta measurement).
More about function blocks you can explore in manufacturer’s ABB manuals:
„Technical Descriptions of Functions: Introduction 1MRS750528-MUM“
„MECU3_ Three-Phase Current Measurement 1MRS752340-MUM“
„MEVO3_ Three-Phase Voltage Measurement 1MRS752345-MUM“
„MEVO1_ Residual Voltage Measurement 1MRS752344-MUM“

 

3. In „Graphic:Measure“ window insert function block MECU3A. Select „Object>Function/Function Block“:

7.5

7.6

7.7

Press OK.

 

4. Select MECU3A block‘s input IL1 and by double pressing right mouse button, open
„Formal Parameter“ window:

7.8

7.9

Here you can to check what of type variable IL1 of block MECU3A should be. In „Data type“ you can check that. The variable IL1 should be SINT type. The same types are also variables IL2 and IL2. SINT means „short integer“ and allocate 8 bits memory in range -128…127.
Function block MECU3A measures 3-phase current.

 

5. Creating variable of SINT type for block MECU3A input IL1. Select „Object>Variable“:

7.10

 

7.11

 

6. In „Variable“ window in „Name“ type „IL1“ and press OK.

7.12

Type data as shown in picture:

7.13

 

7. Variable IL1 connect to block‘s MECU3A input IL1. For this purpose use „Connect objects“ button:

7.14

8. In the same manner create variable IL2 and connect it to block‘s MECU3A input IL2:

7.15

7.16

 

9. Creating of variable IL3 and connecting it to function block:

7.17

7.18

All 3 variables IL1, IL2, IL3 and function block MECU3A:

7.19

How to read FBD circuit (scheme). This scheme you should read from left to right. Current IL1 per variable IL1 is supplead to function block‘s MECU3A input IL1. Variable IL1 is assert to physical channel 2 of PLC REF543 (see article no.5 „CAP505 setting analogues channels).
Function block MECU3A asserts currents IL1, IL2, per variables IL1, IL2, IL3 and outputs measurements IL1MEAS, IL2MEAS, IL3MEAS.

 

10. Configuring current IL2 measurement to PLC’s HMI. Insert function block MMIDATA1:

7.20

Function block‘s MECU3A output IL2MEAS connect to function block‘s MMIDATA1 input DATA:

7.21

 

11. Create variable „TRUE“ (always logical „1“) and connect it to function block‘s MMIDATA1 input „ON“:

7.22

7.23Function block MMIDATA1 is used to output current IL2 on PLC‘s HMI. If Variable „TRUE“ is connected to function block‘s MMIDATA1 input „ON“, then on HMI always data of IL2 current is visible.
More about function block MMIDATA1 you can read in ABB manual „MMIDATA_ MIMIC Dynamic Datapoint 1MRS752356-MUM“.

 

12. Creating voltage measurements. Insert function block MEV03A:

7.24

13. Create variable U12:

7.25

Variable‘s data:

7.26

 

13. Create variable U23:

7.27

7.28

7.29

 

14. Create variable U31:

7.30

7.31

7.32

 

Variables U12, U23, U31 are SINT type: you can check this for example, by selecting function block‘s MEV03A input UL1_U12 and by double clicking on right mouse button:

7.33

 

15. After creating variables U12, U23, U31 connect them to function block‘s MEV03A inputs as shown in picture:

7.34

 

16. Connect function block‘s MECU3A (see particle no. 10 of this article) output UL2_U23MEAS to MMIDATA2 input „DATA“:

7.35

 

17. Insert function block MEV01A and variable Uo:

7.36

7.37

Variable‘s Uo parameters:

7.38

7.39

 

Variable Uo is configured to PLC‘s REF543 measurement channels 7 (see article no.6 „Setting analogues channels of CAP505“):

7.40

 

18. Now we have 3 function blocks MEC03A , MEV01A, MEV03A with variables IL1, IL2, IL3, U12, U23, U31, Uo:

7.41

 

19. Compile project configuration by choosing command MAKE>MAKE:

7.42

More about PLC REF54x configuration read in ABB manuals ”Protection & Control Terminals REF 54_, REM 54_, RET 54_, REC 523 Configuration Guideline 1MRS750745-MUM” and “Technical Descriptions of Functions Introduction 1MRS750528-MUM”.  More about function blocks you can explore in manufacturer’s ABB manuals:
„MECU3_ Three-Phase Current Measurement 1MRS752340-MUM“
„MEVO3_ Three-Phase Voltage Measurement 1MRS752345-MUM“
„MEVO1_ Residual Voltage Measurement 1MRS752344-MUM“

Project configuration has been successfully compiled. In the next article we explore „Relay Mimic Editor“ tool. With this tool we can visualize currents and voltage measurements on PLC‘s HMI.