FieldengInstrumentation & Controls
PID Error
Controller error e = SP − PV (reverse) or PV − SP (direct). Dimensionless engineering units.
Instrumentation & Controls
Controller error e = SP − PV (reverse) or PV − SP (direct). Dimensionless engineering units.
App id: INST-32. Reference version 1.0.
How to fill it
Fill the inputs. The tool shows the outputs.
On the tool screen, Calc is the working sheet. Presets stores values you reuse. Reference is the formula, assumptions, and provenance below.
Formula
e = SP − PV (reverse action)Inputs
| Name | Unit |
|---|---|
| Setpoint | 1 |
| Process variable | 1 |
| Action (0=reverse, 1=direct) (optional) | 1 |
Outputs
| Name | Unit |
|---|---|
| Error (hero result) | 1 |
| Sign | 1 |
Diagnose
This tool does not attach diagnose observations.
Assumptions
- Leave action blank for reverse. SP and PV are dimensionless so mixed unit systems are not converted.
Provenance
- Reverse action is the common heating/fail-closed convention. Direct: cooling or fail-open.