4 identifier, 5 indication of the signal type, 6 examples of variable identifiers – Lenze DDS v2.0 User Manual

Page 24: Identifier, Indication of the signal type, Examples of variable identifiers, Appendix

Advertising
background image

Introduction to IEC 61131-3 programming

Appendix

22

L

DDS-IEC61131 EN 2.0

6.2.4

Identifier

The identifier is the proper name of a variable and should indicate the application or function of the
variable.

Identifiers always start with a capital letter.

If an identifier is assembled from several ” words” , then each ” word” must start with a capital
letter.

All other letters are written in lower case.

Examples of identifiers:

JogValue

NumberOfValues

CurrentSelectedJogValue

6.2.5

Indication of the signal type

In general, it is possible to assign a certain signal type to the inputs and outputs of Lenze function
blocks/system blocks. There are digital, analog, position and speed signals.

A corresponding ending (preceded by an underscore) is added to the identifier of the input/output
variable to indicate the signal type.

Signal type

Ending

Memory

Normalization

(external value ≡≡≡≡ internal value)

Previous

designation

analog

_a

(analog)

16 bits

100 %

≡ 16384

H

digital

_b

(binary)

G

Phase-angle difference or
speed

_v

(velocity)

16 bits

15000 rpm

≡ 16384

F

Phase-angle or position

_p

(position)

32 bits

1 motor revolution

≡ 65535

E

6.2.6

Examples of variable identifiers

Variable identifier

Assigned
system block

Variable type

Data type

Signal type

Application/function

g_anFixSetSpeedValue_a

-

VAR_GLOBAL

Array (Integer)

analog

Array for fixed setpoints

CAN2_nOutW1_a

CAN2_IO

-

Integer

analog

Output word 1 of CAN2_OUT

AOUT1_nOut_a

AOUT1

-

Integer

analog

Output analog signal

bQSP_b

-

-

Bool

binary
(TRUE/FALSE)

Activation of quick stop

byFunction

-

-

Byte

-

Function selection

dnIn1_p

-

-

Double Integer position

Phase input signal 1

nVp

-

-

Integer

-

Gain

Show/Hide Bookmarks

Advertising