关键词在所有编辑器都是大写字母。

以下字符串是关键词，不能作为变量或者POU的 ⇘ 标识符来使用：

⇘ ABS

⇘ ACOS

动作（只用于输出格式）：

⇘ ADD

⇘ ADR

⇘ AND

⇘ ANDN

⇘ ARRAY

⇘ ASIN

⇘ AT

⇘ ATAN

⇘ BITADR

⇘ BOOL

BY

⇘ BYTE

⇘ CAL

CALC

CALCN

⇘ CASE

⇘ CONSTANT

⇘ COS

⇘ DATE

⇘ DINT

⇘ DIV

⇘ DO

⇘ DT

⇘ DWORD

⇘ ELSE

⇘ ELSIF

END_ACTION(只用于输出格式)

⇘ END_CASE

⇘ END_FOR

END_FUNCTION (只用于输出格式)

END_FUNCTION_BLOCK (只用于输出格式)

⇘ END_IF

END_PROGRAM (只用于输出格式)

⇘ END_REPEAT

END_STRUCT

END_TYPE

⇘ END_VAR

⇘ END_WHILE

⇘ EQ

EXIT

⇘ EXP

⇘ EXPT

⇘ FALSE

⇘ FOR

⇘ FUNCTION

⇘ FUNCTION_BLOCK

⇘ GE

⇘ GT

⇘ IF

⇘ INDEXOF

⇘ INT

JMP

JMPC

JMPCN

LD

LDN

⇘ LE

⇘ LINT

⇘ LN

⇘ LOG

⇘ LREAL

⇘ LT

⇘ LTIME

⇘ LWORD

⇘ MAX

⇘ METHOD

⇘ MIN

⇘ MOD

⇘ MOVE

⇘ MUL

⇘ MUX

⇘ NE

⇘ NOT

OF

⇘ OR

⇘ ORN

⇘ PARAMS

⇘ PERSISTENT

⇘ POINTER

⇘ PROGRAM

R

READ_ONLY

READ_WRITE

⇘ REAL

⇘ REFERENCE

⇘ REPEAT

RET

⇘ RETAIN

RETC

RETCN

⇘ RETURN

⇘ ROL

⇘ ROR

S

⇘ SEL

⇘ SHL

⇘ SHR

⇘ SIN

⇘ SINT

SIZEOF

⇘ SUPER

⇘ SQRT

ST

STN

⇘ STRING

⇘ STRUCT

⇘ SUPER

⇘ SUB

⇘ TAN

⇘ THEN

⇘ THIS

⇘ TIME

TO

⇘ TOD

⇘ TRUE

⇘ TRUNC

TYPE

⇘ UDINT

⇘ UINT

⇘ ULINT

⇘ UNTIL

⇘ USINT

⇘ VAR

VAR_ACCESS（只在特殊情况下使用，取决于硬件）

⇘ VAR_CONFIG

⇘ VAR_EXTERNAL

⇘ VAR_GLOBAL

⇘ VAR_IN_OUT

⇘ VAR_INPUT

⇘ VAR_OUTPUT

⇘ VAR_STAT

⇘ VAR_TEMP

⇘ WHILE

⇘ WORD

⇘ WSTRING

XOR

XORN

另外，输入帮助列表中所有的 转换运算符都作为关键词处理。