Operands

Ladder elements and functions are linked to operands. Operands contain data. The Ladder elements and functions determine the way that operand data is used in your program. Every Operand has an Address and a Description. When you select a Ladder element and place it in a net, the Select Operand and Address box opens, enabling you to link an Operand type, select an address, and assign a description.

Note that there are differences between Standard and Enhanced Vision Divisions.

To View Operand Lists

Select the Operand tab at the bottom of the Output Window; the operands are displayed.
Click an operand type in the left pane; a list of that operand type is displayed.

Note that you can edit values and descriptions in the Output Window.

Operand Types and Symbols

Type	Symbol	Quantity (Standard+V130)	Quantity (Enhanced)	Value	Address Range (Standard)	Address Range (Enhanced)
Input	I	544		Bit	I0-I543
Output	O	544		Bit	O0-O543
Timer	T	192	384	32-bit	T0-T191	T0-T383
Counters (C)	c	24	32	16-bit	C0-C24	C0-C31
Memory Bit	MB	4096	8192	Bit	MB0-MB4095	MB0-MB8191
Memory Integer	MI	2048	4095	16-bit	MI0-MI2047	MI0-MI4094
Memory Long Integer	ML	256	512	32-bit	ML0-ML255	ML0-ML511
Double Word (unsigned)	DW	64	256	32-bit	DW0-DW63	DW0-DW255
Memory Floating Point Integer	MF	24	64	32	MF0-MF24	MF0-MF63
Constant Value	#	Dynamic			Dynamic

X Operands (Enhanced only)

X Operands are processed within the CPU's RAM memory. Use them in subroutines where scan time is critical, as for example during Interrupt Routines.

Note that X Operand values are not retained, meaning that they are not backed up by battery.

Type	Symbol	Quantity	Value	Address Range
X Bit	XB	1024	Bit	XB0-XB1023
X Integer	XI	512	16-bit	XI0-XI511
X Long Integer	XL	256	32-bit	XL0-XL255
X Double Word (unsigned)	XDW	64	32-bit	XDW0-XDW63

System Operands

System Operands are connected to certain functions and values in the controller's operating system.

Type	Symbol	Quantity	Value	Address Range
System Bit	SB	512	Bit	SB0-SB511
System Integer	SI	512	16-bit	SI0-SI511
System Long Integer	SL	56	32-bit	SL0-SL63
System Double Word (unsigned	SDW	64	32-bit

Network Operand Types and Symbols

If a controller is networked, the following operands are accessible to other controllers:

Type	Symbol	Quantity	Value	Address Range
Network System Bit	NSB	8	Bit	SB200-SB207
Network Input	NI	17	Bit	I0-I16
Network System Integer	NSI	2	16-bit	SI200-SI201