SpecCalc Hub
Compare common IEC-style and ANSI-style electrical symbols with clear vector sketches. Identify resistors, contacts, motors, fuses and earth references.
Original recognition sketches, not a complete IEC/ANSI library. Use the project legend and the specified standard for an actual drawing.
Common IEC-style convention; R identifies a resistor, not its resistance value.
Common ANSI/IEEE-style convention. The same component can use a different drawing convention.
Two separated plates; a polarized capacitor requires additional polarity identification.
A coil shape alone does not state inductance, core material, or a relay's contact arrangement.
An overcurrent device. The symbol alone does not specify the fuse's rated current or breaking capacity.
Shown in its defined normal, unactuated state; this is not proof that a circuit is de-energized.
M identifies a motor. Starter, overload and short-circuit protection must be identified separately in the drawing.
Check the legend: earth, protective earth, chassis and signal common must not be assumed interchangeable.
Text sketches are not an IEC/ANSI drafting library. Use the project legend for exact graphical symbols.
| Component | Text sketch | Function |
|---|---|---|
| Resistor | —[R]— | Resistance and voltage/current relationship |
| Capacitor | —| |— | Stores electric-field energy |
| Inductor | —oooo— | Stores magnetic-field energy |
| Switch | —o/ o— | Opens or closes a circuit |
| Fuse | —[F]— | Overcurrent protection element |
| Earth | ⏚ | Earth connection; not interchangeable with every signal-ground symbol |
| Transformer | L1 ‖ L2 | Magnetically coupled windings |
| Motor | (M) | Motor function; ratings are specified separately |
Start with the drawing legend, not a symbol guessed in isolation. The gallery compares recognizable component shapes; terminal numbers, reference designators and the circuit context establish what a particular device does.
Recognize a component’s function from its schematic symbol, then use its reference designator and the drawing legend to find specifications.
Electrical symbols let you read a schematic without seeing the physical device. A switch, fuse, motor, earth connection or resistor is normally represented by a compact symbol so the drawing stays readable even when the real installation is large.
This reference is useful for electricians, students, maintenance teams and buyers who need to understand what a drawing is describing before they compare parts, trace a fault or review a cable schedule.
IEC 60617 covers graphical symbols for diagrams. IEC 60417 and ISO 7000 concern symbols on equipment and are not interchangeable diagram catalogues. “ANSI vs IEC” describes a drawing-convention question, not an electrical performance rating.
The page is structured as a practical reference: start with the visible table, diagram and labels, then compare them with the exact connector, device, enclosure or symbol set in front of you.
Use the listed sources to confirm revision, naming and application context. Similar labels can hide different electrical limits, pin functions or test conditions, so the page should be treated as a guided reference rather than a universal standard text.
A rectangle and a zigzag may both represent a resistor. If the drawing says R1 = 10 kΩ, that value comes from the label or parts list, not the shape. A normally open contact is drawn in its defined normal state; it does not certify that a live machine is safe to touch.
A resistor, capacitor and switch in one branch usually mean the designer wants timing, filtering or suppression, not just a plain on/off path. Reading the three symbols together is more useful than reading each one in isolation.
If you see earth, fuse and motor symbols on one feeder, the drawing is showing both protection and the connected load. The symbol tells you the device class, but not its final rating. The rating must still be verified in the schedule, datasheet or project notes.
They are different drawing conventions for the same component function. Follow the legend and the specified standard, and obtain the resistance and power rating from the part data.
No. Identify the separate protective functions and check the device documentation. A motor symbol contains no trip curve, breaking capacity or ground-fault protection claim.
Not necessarily. Equipment markings communicate controls or functions to the user; circuit symbols describe electrical relationships. Check the applicable symbol set rather than mixing the two.
Not always. The general function may be the same, but the exact graphic style and notation can differ between IEC, ANSI and manufacturer drawings.
No. Use the symbol page to identify the item, then check the schedule, datasheet and project notes for ratings and selection details.
Because many drawings reuse similar shapes for different contexts. The legend tells you how that project defines the symbol set.
Explanation updated: 2026-09-16
This calculator provides an estimate for informational purposes only. It is not a certified engineering design, electrical safety approval, or professional installation recommendation. Always verify final decisions with a qualified professional and applicable local codes.