University:
University of Michigan
Course:
PHYSICS 250 | Fundamental Physics for the Life Sciences II
Academic year:

2021
Views:

239

Pages:

8
Author:

ui4s3l4md25

Comparison of NEMA and IEC schematic diagrams General With the increasing emphasis on globalization, many industries are now looking to all parts of the world to produce, market, and sell their products. Electrical manufacturers are no exception. Since the electrical standards adopted by various nations may vary, the markings and symbols used to describe electrical control products vary as well. Whether it is a complex control system on a machine tool or a simple across-the-line motor starter, the need to recognize and understand these symbols becomes more important. It is possible that products from all parts of the world are being used in any one facility. The purpose of this document is to provide a simple cross reference of common schematic/wiring diagram symbols used throughout various parts of the world. The following tables describe the device and show the symbol by area of usage. Description Capacitor Circuit breaker NEMAT Magnetic only Thermal-magnetic Coil Basic contacts Normally closed Normally open Time delay contacts Normally closed, time closed Normally closed, time open Normally open, time closed Normally open, time open Disconnect switch Non-fused Fused Fuse IEC Comparison of NEMA and IEC schematic diagrams Description NEMAT IEC Earth (ground) Induction motor Single-phase Three-phase Indicating lights Standard Insert color code inside symbol Insert color code next to symbol Push-to-test Insert color code inside symbol Meters Insert function code inside symbol Overload relays Thermal element Magnetic element Pushbuttons Illuminated Momentary (N.C.) Momentary (N.O.) Mushroom head (N.C.) Mushroom head (N.O.) Resistor Insert function code next to symbol Description Switches NEMAT Float (N.C.) Float (N.O.) Flow (N.C.) Flow (N.O.) Foot (N.C.) Foot (N.O.) Limit (N.C.) Limit (N.O.) Selector switch Two-position Three-position IEC Description Switches NEMAT Pressure (N.C.) Pressure (N.O.) Temperature (N.C.) Temperature (N.O.) Transformer Current Voltage IEC Description NEMAT Common Schematic Diagrams: Across the Line Non-Reversing Starters with Start–Stop Pushbuttons Power circuit Control circuit Common Schematic Diagrams: Across the Line Non-Reversing Starters with Hand–Off–Auto Selector Switch Power circuit—starter Control circuit—starter IEC Description NEMAT Common Schematic Diagrams: Across the Line Reversing Starters with Forward–Reverse–Stop Pushbuttons Power circuit— reversing starter Control circuit— reversing starter Common Schematic Diagrams: Combination Starter with Fused Disconnect Switch and Start–Stop Pushbuttons Power circuit IEC Description NEMAT Common Schematic Diagrams: Combination Starter with Fused Disconnect Switch and Start–Stop Pushbuttons Control circuit Common Schematic Diagrams: Manual Starter Power circuit IEC