Lessons
Symbol guide
A visual reference to the pictograms used throughout Do It Your Ohm.
Why these drawings look like the things they name
We use pictograms on purpose. They make a first drawing recognisable before a learner needs a separate convention. Reading formal schematics is a later skill.
Our pictogram vocabulary
These are the 21 pictograms currently used across the course. This is a reference, not a lesson or a test.
- Power source
- Lamp
- Empty socket
- Switch
- Board pad
- Resistance
- Contact point
- Open contact
- Wire
- Person
- Heater
- Heat
- Heating joint
- Motor
- Plug
- Lamp holder
- Extension lead
- Appliance socket
- Plugged fixture
- Overhead line
- Bird
Standards comparison
We draw pictograms on purpose, so a first drawing reads before you need a separate convention. In official published standards, some of the same parts are drawn differently — this table shows what each standard prints for the symbols where they differ. It names where each standard comes from, not which one you must follow: that is a separate question for a qualified electrician in your country.
| Symbol | Our pictogram | ANSI/IEEE 315-1975United States | IEC 60617International | GOSTCIS |
|---|---|---|---|---|
| Power source | ||||
| Lamp | ||||
| Switch | ||||
| Resistance |
Sources
- ANSI/IEEE 315-1975: ANSI/IEEE 315-1975
- IEC 60617: IEC 60617
- GOST: GOST 2.721-74; GOST 2.728-74; GOST 2.732-68; GOST 2.755-87
- Power source (ANSI/IEEE 315-1975): ANSI/IEEE 315-1975 §2.5 (mohandesbiaziat.ir ANSI-Y32.2 scan) — long thin line (plus) and short thick line (minus) per cell
- Power source (GOST): GOST 2.721-74 (masandilov.ru) — long thin line (plus) and short thick line (minus) per cell
- Lamp (IEC 60617): IEC 60617 — circle with an inscribed X
- Lamp (GOST): GOST 2.732-68 — circle with X (one designation for lighting and signal)
- Switch (ANSI/IEEE 315-1975): ANSI/IEEE 315-1975 §4.6 — angled arm over a gap, drawn open (de-energised-resting rule)
- Switch (GOST): GOST 2.755-87 (ruscable.ru) — angled arm over a gap, drawn open (de-energised-resting rule)
- Resistance (ANSI/IEEE 315-1975): ANSI/IEEE 315-1975 — zigzag ('looks like a spring')
- Resistance (IEC 60617): IEC 60617 (qelectrotech scan) — long empty rectangle, about 2.5:1
- Resistance (GOST): GOST 2.728-74 (meganorm.ru scan) — same rectangle as IEC; wattage marks may sit inside (not drawn here)