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What is the ⎓ symbol called, which looks similar to an equals sign with the bottom line broken into 3 dashes, and is used in consumer electronics?

Equal sign highlighted

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    \$\begingroup\$ I just use the @ symbol. \$\endgroup\$
    – DKNguyen
    Apr 30, 2023 at 19:33
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    \$\begingroup\$ @DKNguyen But that doesn't tell you it's DC. \$\endgroup\$
    – marcelm
    May 1, 2023 at 11:23
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    \$\begingroup\$ @marcelm Well you can just write VDC. \$\endgroup\$
    – DKNguyen
    May 1, 2023 at 14:28
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    \$\begingroup\$ compart.com/en/unicode/U+2393 \$\endgroup\$
    – glglgl
    May 2, 2023 at 8:29
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    \$\begingroup\$ babelstone.co.uk/Unicode/whatisit.html is a handy resource for things like this. At least, it tells you what the official Unicode name is for things. shapecatcher.com can help alongside it if you don't know the codepoint. \$\endgroup\$
    – Hearth
    May 2, 2023 at 14:30

4 Answers 4

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This is not an 'Equal' Sign in math-terms.

It's a sign used by convention to denote DC-systems.

In your screenshot it means: Can draw/deliver upto 3A-DC at 5V-DC

Edit 3:

Removed previous edits.

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    \$\begingroup\$ But what's the symbol called? The question from the title is "What is the ⎓ symbol called?" \$\endgroup\$ May 1, 2023 at 21:32
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    \$\begingroup\$ @JoshuaTaylor You are asking the good questions :) I have no idea to be honest. I would go with (See other answers) 'Direct Current Symbol, Form Two' according to codepoints.net/U+2393 \$\endgroup\$ May 1, 2023 at 21:35
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If you need the corresponding Unicode character, it's U+2393 DIRECT CURRENT SYMBOL FORM TWO, “⎓” (might not be displayed properly if you don't have a suitable font).

The “Form Two” in the name comes from the IEC 61286 standard, which in some version also had “Direct Current Symbol Form One”, apparently looking like a single horizontal line; that “Form One” did not get a separate codepoint in Unicode.

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    \$\begingroup\$ This is the only answer so far that answers the question in the title: "What is the ⎓ symbol called?" \$\endgroup\$ May 1, 2023 at 21:34
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_____  DC voltage
_ _ _  ground reference

The symbol solid line represents a graphical plot of the output voltage with the dashed line representing the 0 V reference.

Since the output voltage is constant and offset from 0 V we can deduce that the output is a DC voltage.

~  AC voltage

AC power supplies use a sinewave or ~ to signify an alternating voltage. This symbol does not show the 0 V reference.

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    \$\begingroup\$ -1 since it doesn't answer the question. \$\endgroup\$ May 2, 2023 at 8:55
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    \$\begingroup\$ @12431234123412341234123 +1. In my opinion, "DC voltage / ground reference" should suffice as an answer on this SE. A question explicitly about Unicode namings should be off-topic. \$\endgroup\$
    – Velvet
    May 2, 2023 at 13:48
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To complement what other people said and NOT answering the OP's title question directly, since on this site we are not concerned on how Unicode named that symbol (as other have mentioned), but how it is named by the relevant Electrical Engineering standard.

According to ISO website, that symbol is referenced in ISO/IEC standard 60417 as symbol no. 5031.

The relevant data are the following:

Reference No: 5031

Registration date: 2002-10-07

Status: Active

Title/Meaning/Referent: Direct current

Function/description: To indicate on the rating plate that the equipment is suitable for direct current only; to identify relevant terminals.

Image content: Lines - multiple straight

Note that the ISO website doesn't unequivocally state that "direct current" is the symbol name, but that it is its meaning (or "title" or "referent"). That is, according to ISO that symbol is "symbol n.5031" and it means "direct current", and then goes on explaining how it is to be used.

In other words, if someone insists (pedantically) on wanting to get a "precise identifier name" (as in a programming language or in a Unicode table) the true (according to ISO) answer is "symbol n.5031" and "direct current" is its meaning.

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    \$\begingroup\$ +1; the ISO standard for symbols on equipment is an ideal source of truth for a symbol found on equipment, including consumer electronics. \$\endgroup\$ May 2, 2023 at 15:25

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