Rockwell Automation 1760-xxxx Pico GFX-70 Controllers User Manual - Manual (Page 153)

Publication 1760-UM002B-EN-P - March 2005
Wiring with Pico GFX-70 4-43
6. actual value plus offset
• Range A: Compare
>I1
>
>I2
– The actual value
>I1
increases.
– The contact switches when the actual reaches the set point value.
– The actual value changes and falls below the value of the set point
value minus the hysteresis.
– The contact goes to the normal position.
• Range B: Compare
>I1
<
>I2
– The actual value drops.
– The contact switches if the actual reaches the set point value.
– The actual value changes and rises above the value of the set point
value plus hysteresis.
– The contact goes to the normal position.
• Range C: Compare
>I1
>
>I2
with offset
– This example behaves as described in Range A. The offset value is
added to the actual value.
• Comparison
>I1
=
>I2
The contact switches on:
– If the set point is exceeded with the actual value rising.
– If the set point is undershot with the actual value decreasing.
The contact switches off:
– If the hysteresis limit is exceeded with the actual value rising.
– If the hysteresis limit is undershot with the actual value decreasing.
Arithmetic Function Block
Pico GFX-70 provides 32 arithmetic function blocks AR01 to AR32.
The arithmetic function block is used for arithmetic operations. All four basic
arithmetic operations are supported:
• add
• subtract
• multiply
• divide