Basler Electric BE1-BPR - Manual (Page 113)

9272000990 Rev J BE1-BPR BESTlogic Programmable Logic 5-7
LO Command
Purpose:
Reads or programs output logic.
Syntax: LO[#[=<Boolean equation>]]
Comments: Access area one password is required to change setting.
LO Command Example:
Turn on output 1 when fault detector 1 or 2 is picked up, the output of timer 1 is TRUE, and the output of
timer 3 is FALSE.
LO1=(F1+F2)T1/T3
Output Programming Examples
Example 1: Using AND/OR logic
Output one (LO1) is TRUE if contact input 1 or 2 (I1 or I2) are closed (TRUE) and fault detector 1 or 2 (F1
or F2) are picked-up (TRUE) and timer 1 (T1) is also TRUE.
Boolean equation: LO1 = (I1+I2)*(F1+F2)*T1
Internal format: LO2=F1T1T2/I2+F2T1T2/I2
Example 2: Using AND/OR/NOT logic
Logical output two (LO2) is TRUE if contact input two is FALSE and timer one (T1) is TRUE and timer two
(T2) is TRUE and fault detector one (F1) or fault detector two (F2) is TRUE.
Boolean equation: LO2=/I2T1T2(F1+F2)
Internal format: LO2=F1T1T2/I2+F2T1T2/I2
Example 3: Using feedback to latch an output
Logical output one (LO1) is TRUE if timer three (T3) is TRUE and contact input 1 (I1) is TRUE or logical
output one (O1) is TRUE. Therefore, when output 1 turns TRUE, it will remain TRUE, latching itself on
independently of I1, until timer T3 turns off.
Boolean equation: LO1=T3(I1+O1)
Internal format: LO1=T3I1+T3O1
Example 4: Overcoming 4 OR Term Limit
Logical Output 1 is TRUE if input contact I1, I2, or I3 are closed (TRUE) and fault detector F1 or F2 are
picked-up (TRUE).
Initial Boolean equation: LO1=(I1+I2+I3)(F1+F2)
Internal format: LO1=I1F1+I1F2+I2F1+I2F2+I3F1+I3F2 (ERROR: >4 Terms)
To correct the error, the equation will be rewritten using a virtual output as an intermediate expression. In
this way, the original 6 term equation can be reduced to one two term and one three term equation.
Initial Boolean equations: LO1=O11(F1+F2) LO11=I1+I2+I3
Internal formats: LO1=F1O11+F2O11 L011=I1+I2+I3
CONTACT INPUT LOGIC
Contact Sensing Input Operation
Adjustable recognition and debounce timer logic monitors the contact sensing inputs and determines
when contact input changes of state are recognized. An example of the function blocks that process and
control contact input logic is shown in Figure 5-2.