Is there any color code convention for tht pins?

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Joe Stavitsky

Joined Apr 5, 2020
107
I have multiple colors of tht pins on hand. Is there any general color code convention for power(+/-), digital signal, analog signal, etc?

Thanks so much

Joe
 

SamR

Joined Mar 19, 2019
4,492
It gets confusing just for power. 12V SAE is RED +, BLK -, Breadboards have a Blue and Red rail typically used for + & - but may also have a GRN connector to connect to ground. 3 Phase power used to be for each phase RED, YEL, BLU, and a BLK neutral if wired Wye and not Delta. Apparently, the NEC is changing that. Residential/Commercial 120V single phase uses BLK for hot, WHT for neutral, and GRN for ground. For 240V it is BLK and BLK (no neutral) and again GRN for ground. As to signal wiring... Sorry, no idea and don't ever remember seeing a standard. There are lots of "In-House" standards used it seems.
 

dl324

Joined Mar 30, 2015
15,462
I have multiple colors of tht pins on hand. Is there any general color code convention for power(+/-), digital signal, analog signal, etc?
You can use whatever you want. I prefer to use brown for everything because I make most of my jumpers and have 2 1000' spools of solid #22 tinned wire with brown insulation.

When I'm using premade jumpers with "DuPont" connectors for many I/O's, I'll use resistor color code order (D0=blk, D1=brwn, D2=red, etc) to help keep the wires straight.
 

Alec_t

Joined Sep 17, 2013
13,232
Residential/Commercial 120V single phase uses BLK for hot, WHT for neutral, and GRN for ground. For 240V it is BLK and BLK (no neutral) and again GRN for ground.
That's for the USA.
In Europe, Live (hot, 240V) is brown, Neutral is blue and Ground is green with a yellow stripe.
 

Ya’akov

Joined Jan 27, 2019
6,856
When I was doing a lot of installations I developed a set of heuristics to deal with the varying colors of wire that I had available in multiconductor cables. Because I always used the same rules, if I ever returned to the installation to do more work I could figure out the meaning of the colors as if I was starting from scratch—this worked very well.

The general idea goes like this:

If there are “standard” colors for the signals, I use them. Standard of course is relative, but it was what I knew to be what I would choose if I had a choice (i.e.: red for positive power, black for negative, green for ground; red for right channel audio, while for left, black for common; etc.)

If one or more colors were not available I would use any standard I could, then use whatever was closest to standard for the others. (e.g.: if I had red, grey, and purple for a stereo audio feed I would use red for right (standard), grey for left (closest to standard) and purple for common—what was left).

If there was no standard colors available, I would use some loose ”rules”. One was “bright is right”—that is I would decide which was the brightest color available (subjectively) and make that right, paired with making the darkest color common. I had several of this nemonic-rules and stuck to them.

This strategy was very effective and I can’t recall it failing to allow me to know which signals were on which wires when returning to a site.I should also point out that we’d always provide documentation to the client which included as-built diagrams and color code information. This just wasn’t always available, and for this aspect I didn’t need it anyway.

One more thought—we would often use 10 core cable for control systems (this was the pre-pervasive-digital days, and a lot of things were simple galvanic connections. Today I would use a network of some kind). These cables inevitably had the resistor color code colors for the conductors. So we would number the connections and use the correct color for that number.

Directly concerning the question: there are no general conventions, but there are contextual ones (which is what @SamR was pointing out, I think). It’s helpful to use those if they are available* but even more important is a slavish consistency on your part, sticking to the same personal conventions every time so you can return to the project and know what is what without tracing.

*Sometimes color codes are mandatory, as in AC mains wiring, obviously in those cases you just “do the right thing”.
 

MisterBill2

Joined Jan 23, 2018
13,805
Within the telecom industry there was (still is) a very definite color code to identify pairs in cables. This worked for cables up to about 600 pairs. But that is a very special case and those colors are not al common elsewhere.
For residential wiring green is always tghe safety ground, black is the hot side and white is the neutral. When there is both a constant hot and a switched hot, the switched line is red. When there is 240 volts plus neutral the second hot should be red or blue, because it is hard to see the difference between black wires, and often it matters.
 

SamR

Joined Mar 19, 2019
4,492
Kinda hard for me to be consistent breadboarding as I use a lot of premade colored jumpers so I am limited to ones that fit the spaces needed to jumper. But when using DuPont jumpers breadboarding or spooled wire Proto-boarding it's Red plus, Black neg, Green gnd, Yellow analog signal, Blue digital signal. Not a hard and fast rule but just my preferences. I opened an old Iambic Memory Keyer I made over 40 years ago and it was almost ALL Blue wire wrap wire (only color available to me back then). No idea where the schematic is after all those years and near impossible to tell by quickly looking as to what was what. So I'll have to look up each components pin-out and re-engineer it. Lot's of memory chips and old TTLs. Someone got curious at an ARRL Field Day and opened it up and shorted something and killed it.
 

SamR

Joined Mar 19, 2019
4,492
That's for the USA.
In Europe, Live (hot, 240V) is brown, Neutral is blue and Ground is green with a yellow stripe.
I think that is what the new NEC is proposing... Just briefly looked at it. After nearly a hundred years of common practice and NOW they want to change it? What a mess...
 

MisterBill2

Joined Jan 23, 2018
13,805
I think that is what the new NEC is proposing... Just briefly looked at it. After nearly a hundred years of common practice and NOW they want to change it? What a mess...
Worse yet, the reason for it, wich seems to be that somebody is calling the black and white scheme racist. At least that is what I heard was the motivation for the change. Never mind that in the RETMA color code black is zero and white is nine.
 
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