---
lang: en
title: "Automatic analog and digital gauge reading"
url: https://nabrio.com/use-cases/gauge-reading
canonical: https://nabrio.com/use-cases/gauge-reading
updated: 2026-10-27
publisher: Nabrio Co., Ltd. (nabrio.com)
---

# Automatic analog and digital gauge reading

Nara reads gauges and meters from a camera: digital displays with OCR, analog dials with needle detection. Values are logged continuously, trended on a dashboard and sent to SCADA, and an alarm is raised when they go out of range.

- Sectors: [Manufacturing](https://nabrio.com/industries/manufacturing.md)
- What it takes: Ready to configure. Works with Nara’s built-in models. You set up the zones, rules and outputs. Digital displays work out of the box. Analog dials need a model trained in Reva or project calibration.
- Products: [Nara](https://nabrio.com/nara.md), [Reva](https://nabrio.com/reva.md)

## The problem

Operators walk rounds to read and write down gauges and meters. Readings are infrequent and sometimes wrong.

## How it works

- **Input:** Camera pointed at the gauge or display
- **Process:** Digital: crop and OCR. Analog: needle detection, converted to a value
- **Action:** Log the value, trend it, alarm when out of range, send it to SCADA

For digital displays, Nara crops the display and reads it with OCR. For analog dials, it detects the needle with keypoints or a custom model and converts its position to a value. Each reading is stored, trended on the dashboard with moving-window statistics, compared with your limits, and sent to SCADA over MQTT or HTTP.

## What you need

- A camera with a fixed view of each gauge or display
- For analog dials: a model trained in Reva or a calibrated setup
- Optional: SCADA reachable over MQTT or HTTP

## Nara building blocks

- Camera nodes
- Crop
- OCR
- Needle detection (keypoints or custom model)
- Maths and moving-window statistics
- Database table
- Dashboard charts
- MQTT and HTTP output

AI models: [OCR (text reading)](https://nabrio.com/nara/ai-models.md)

## What it improves

- Walk rounds removed
- Continuous readings instead of one per shift
- Earlier warnings

## Frequently asked questions

### Does it work with old analog gauges?

Yes. Analog dials are read by detecting the needle, with a model trained in Reva or a calibrated setup, and converting its position to a value.

### Does it need an internet connection?

No. Nara runs on your own hardware on the local network, and images and results stay on-site. Eligible tiers also support offline licensing locked to the hardware.

## Related use cases

- [Machine status monitoring](https://nabrio.com/use-cases/machine-status-monitoring.md)
- [Barcode and label inspection](https://nabrio.com/use-cases/barcode-and-label-inspection.md)
- [Visual quality inspection](https://nabrio.com/use-cases/visual-quality-inspection.md)

Talk to us about gauge reading: sales@nabrio.com. [Download Nara](https://nabrio.com/download.md).