Omron NJ501-1500 User Manual

2 Instruction Descriptions
2-14
NJ-series Instructions Reference Manual (W502)
LD and LDN
None
z LD
The LD instruction reads the value of the specified BOOL variable and outputs it to the next instruction.
If the value of the specified variable is TRUE, then TRUE is output. If the value is FALSE, then FALSE is
output. Use the LD instruction for the first NO bit from the bus bar or for the first NO bit of a logic block.
z LDN
The LD instruction reads the inverse of the value of the specified BOOL variable and outputs it to the
next instruction. If the value of the specified variable is TRUE, then FALSE is output. If the value is
FALSE, then TRUE is output. Use the LDN instruction for the first NC bit from the bus bar or for the first
NC bit of a logic block.
The operation is as shown below if you do not specify upward or downward differentiation.
LD: Reads the value of a BOOL variable.
LDN: Reads the inverse of the value of a BOOL variable.
Instruction Name FB/FUN Graphic expression ST expression
LD Load --- None
LDN Load NOT --- None
Variables
Function
Instruction
Value of
variable
Output
value
LD
TRUE TRUE
FALSE FALSE
LDN
TRUE FALSE
FALSE TRUE
Variable
Downward
differentiation
Upward
differentiation
Variable
Variable
VariableVariable Variable
Upward
differentiation
Downward
differentiation

Omron NJ501-1500 Specifications

General

Brand	Omron
Model	NJ501-1500
Category	Controller
Language	English