KiCad - A Cross Platform and Open Source Electronics Design Automation Suite
AutoCAD MEP - AutoCAD MEP software helps you draft, design, and document building systems.
Proteus PCB design - Proteus PCB design combines the schematic capture and ARES PCB layout programs to provide a...
DataCAD - DataCAD is a computer-aided design and drafting software for 2D and 3D architectural design and drafting
QUCS - Qucs, briefly for Quite Universal Circuit Simulator, is an integrated circuit simulator which means you are able to setup a circuit with a graphical user interface (GUI) and simulate the large-signal, small-signal and noise behaviour of the circuit.
AutoCAD Plant 3D - AutoCAD Plant 3D is a BIM software that lets you create, modify, and manage schematic piping and instrumentation diagrams.