FieldengElectrical & Power
Automotive Voltage Check
Contextual interpretation of a measured vehicle battery voltage.
Electrical & Power
Contextual interpretation of a measured vehicle battery voltage.
App id: ELEC-16. 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
Compare measured voltage to typical resting and charging bandsInputs
| Name | Unit |
|---|---|
| Measured battery voltage (camera) | V |
| Engine state (0 = off, 1 = running) | 1 |
| Nominal system voltage (optional) | V |
Outputs
| Name | Unit |
|---|---|
| Measured voltage (hero result) | V |
| Engine state | 1 |
| Nominal system voltage | V |
Diagnose
Observations are context. They do not pass or fail a structure. See Diagnose.
| When | Observation | Severity |
|---|---|---|
Engine state ≠ 1 and Measured voltage ≥ 12.4 * (Nominal system voltage / 12) | Normal resting-voltage range | info |
Engine state ≠ 1 and Measured voltage < 12.2 * (Nominal system voltage / 12) | Low resting voltage | caution |
Engine state ≠ 1 | Intermediate resting voltage | info |
Measured voltage ≥ 13.5 * (Nominal system voltage / 12) and Measured voltage ≤ 14.8 * (Nominal system voltage / 12) | Charging voltage present | info |
Measured voltage < 13.2 * (Nominal system voltage / 12) | Limited charging voltage | warning |
Measured voltage ≥ 13.2 * (Nominal system voltage / 12) | Charging voltage outside typical band | caution |
Assumptions
- Engine state 0 is off, 1 is running. Nominal voltage defaults to 12 V and scales the example bands.
- Temperature, chemistry, smart charging, and measurement location are not modeled.
Provenance
- Contextual findings for a conventional lead-acid system, not a battery-health verdict.