What is the best open source SCADA software?

Following are few open source SCADA softwares:

1. Free Scada

Supported OS: Windows

License: Freeware

Free SCADA provides for end-users flexible tools for visualization and interactive control of any industrial process.

2. IndigoSCADA

Supported OS: Windows, Linux

License: GPL

A small footprint SCADA system entirely developed in C and C++ with multiple OS support and multiple front end protocol drivers.

3. openDAX

Supported OS: Linux

License: GPL

OpenDAX is an open source, modular, data acquisition and control system.

4. openSCADA

Supported OS: Windows, Linux

License: GPL

openSCADA is an open source Supervisory Control And Data Acquisition System. It is platform independent and based on a modern system design that provides security and flexibility at the same time.

5. S.E.E.R. 2

Supported OS: Linux

License: GPL

S.E.E.R. 2 is a full featured SCADA / Historian / Aggregate Analysis System developed to work as a ‘front end’ for mod_openopc.

6. SCADA ProcessViewer

Supported OS: Windows

License: GPL

Crossplatform SCADA written in Free Pascal language

7. ScadaBR

Supported OS: Windows

License: GPL

ScadaBR is a SCADA (Supervisory Control and Data Acquisition) system with applications in Process Control and Automation, being developed and distributed using the open source model

8. Szarp

Supported OS: Windows, Linux

License: GPL

SZARP is a full-featured, open source SCADA system for Linux. Client programs are available for Linux and Windows.

You may compare the features of these in detail and decide which is the best suitable for you.