Ladder diagrams are specialized schematics commonly used to document industrial control logic systems. They are called "ladder" diagrams because they resemble a ladder, with two vertical rails (supply power) and as many "rungs" (horizontal lines) as there are control circuits to. In the AC circuits common in industrial settings, you'll work with three main wires: Hot Wire: This is your current-carrying conductor, usually black or red. It brings power from the source, through the switch, and out to the load (like a motor, light, or solenoid). This is the wire the switch is. Standard electrical IEC symbols also known as IEC 60617 (British Standard BS 3939) used to represent various devices including pilot lights, relays, timers and switches for usage in electrical schematic diagrams Tip: Streamline your electrical design process and improve your workflow with Capital X. This course gets you up to speed on understanding what makes up an industrial control panel. An overview of IEC Basic panel design criteria and standards is provided. It also provides enhanced component protection, inrush current protection, and minimizes printed-circuit board (PCB) size. Motors – Represented by a circle with “M” inside.