Dot inside a C, with + and − (DC plug polarity)
Shows the polarity of a DC barrel plug or socket. The sign joined to the dot is the polarity of the centre pin (tip). The sign joined to the C is the outer sleeve. Dot to + means centre positive.
Symbol reference: IEC 60417-5926
A mark tells you what the maker declares, never that the product is safe.
- What it looks like
- A solid dot inside an open circle shaped like a C, with a line from the dot to one side and a line from the C to the other, ending in + and − signs.
- Who may apply it
- The power-supply or device maker.
What it does not promise
It does not make two supplies interchangeable. The plug size, voltage and current must match too, and you cannot reliably tell polarity, voltage or even AC versus DC by looking at a connector. A plug with the wrong polarity can damage a device even when the voltage is right.
Sources
Each page below was fetched and read on the date shown. Where a symbol’s IEC 60417 or ISO 7000 number is given, a public page listing that number is among them.
- Wikimedia Commons: File page for the polarity symbol, IEC 60417 No. 5926 / JEITA CP-1104B No. 1030 — “The polarity symbol of the D.C. power supply. IEC 60417 No.5926 Polarity of d.c. power connector / JEITA CP-1104B No.1030 DC INPUT/OUTPUT”. Checked 2026-09-24.
- Wikipedia: Polarity symbols (the article itself flags that it lacks inline citations) — “The symbol connected to the dot (usually the symbol found to the right) denotes the polarity of the center/tip, whereas the symbol connected to the broken circle denotes the polarity of the barrel/ring.” Checked 2026-09-24.
- Wikipedia: DC connector — “Inverted polarity plugs can and do damage circuitry when plugged in, even if the voltage is correct”; it is not possible to reliably infer power parameters (current, voltage, polarity, even AC or DC) by examining the connector. Checked 2026-09-24.
Written in our own words; quotations are the sources’ wording.