---
title: Collectors
slug: concepts/collectors
docTags: GOo15ntkoXThxPf_Z8vVm
createdAt: 2025-07-17T09:19:30.172Z
---

## What is a Collector?

A **collector** is a software component that connects to your industrial equipment (like PLCs, sensors, or SCADA systems) and sends their data to Factry Historian.

Think of it as the bridge between your equipment on the shop floor and the Factry Historian data platform.

## Why does it matter?

Without collectors, Factry Historian has nothing to store.

They ensure that real-time measurements from machines and processes arrive in the database, where they can be visualized, analyzed, and used for decision-making.

## How does it fit in the system?

Collectors are the **starting point** of the data flow:

:::BlockQuote
Machines → **Collector** → Historian → Visualizations / Reports
:::

A collector is configured to talk to specific devices using industrial protocols (like OPC-UA, Modbus, etc.) and deliver measurements into the Historian.

The specific data that is collected is called [Measurements](docId\:XQWLEmDcNfff3-0H-GMmS), which may also feed [Calculations](docId\:OpIoDkGNNgYjeDX6zkg_D) and [Events](docId:0Ith2zLcAIs5YYwhSdTjE). Measurements can be attached to [Assets](docId\:C4opdlUcIrJ0DRaeXrIsp) as [Asset Properties](docId\:Cr6HbrDSl8FsuVlVm20IF), and can be selectively forwarded using [Sinks & Forwarders](docId\:XcOj5kic2xMxSZ4InAS_-).

Collectors work according to a store-and-forward mechanism. Collectors will buffer data on disk when they do not receive an acknowledgment from Factry Historian that the data is successfully stored, e.g. because of network issues.

## Example

You have a packaging line with a PLC that records conveyor speed and temperature.

You configure a collector to connect to this PLC over OPC-UA. The collector sends 2 measurements:

- *conveyor\_speed*: 1.4 m/s
- *temperature*: 72°C

 ... every second, into Factry Historian.

## When you use it

A functional Factry Historian will always have at least 1 collector.

You’ll interact with collectors when:

- Setting up the Historian for a new site or production line.
- Adding a new data source (e.g. a new PLC) to your monitoring.
- Troubleshooting missing or inconsistent data from a specific device.

Typically, once configured correctly, collectors run in the background without much intervention.

## Common misconceptions

- A collector is **not** meant to store data itself, with the exception of its buffering capabilities in case of any network issues. A collector only forwards data to the Historian.
- You don’t need one collector per measurement; one collector connects to one data source (e.g. an OPC-UA server) and can retrieve many measurements from it.
- If data is missing, it’s not always the collector at fault. It could be the device, the network, or Historian configuration.

## Best practices

- In the case of client-server protocols (e.g. OPC-UA, OPC-DA), run the collectors as close to the data source as the network allows. This reduces the risk of data loss from network issues. Always respect security guidelines.
- Set up monitoring and automatic alerts for collectors using the Portal.

## More information

- [Installing a collector](docId\:Iv4_SD56TdxcqKRKCj4kv) 
- [Configuring a collector](docId:3fYs7rs2FLI2rDgV2zV7g)