Limit Test (LIM) Instruction in Ladder Logics

The Limit Test (LIM) instruction in ladder logics is used to test for values within or outside a specified range, depending on how you set the limits.

The Low Limit, Test, and High Limit values can be word addresses or constants, restricted to the following combinations:

If the Test parameter is a program constant, both the Low Limit and High Limit parameters must be word addresses.

If the Test parameter is a word address, the Low Limit and High Limit parameters can be either a program constant or a word address.

Limit Test (LIM) Instruction

Limit%20Test%20(LIM)%20Instruction%20in%20Ladder%20Logics

True/False Status of the LIM Instruction

If the Low Limit has a value equal to or less than the High Limit, the instruction is true when the Test value is between the limits or is equal to either limit.

If the Low Limit has a value greater than the High Limit, the instruction is false when the Test value is between the limits.

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Video Tutorial on Limit Test Instruction (AB PLC)

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