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Standard Color for indicator lights 10

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wfmoore

Electrical
Mar 4, 2003
2
I am looking for an available standard that provides guidance for using indicator lights.

The confusion is that in the Power Industry "Red" is traditionally used to indicate running.

In my manufacturing experience, "Green" is used for running. This is derived I believe from the old "JIC" standard that is no longer supported. Is there an industry standard that specifies or recommends a position

Thanks

William F. Moore
 
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Suggestion to the previous posting: I have been looking for many withdrawn standards. Standards are just living documents. Specifying engineers have some leeway to select appropriate standards on various projects.
 
this is clear
red-machine breaker is close m/cis running without any fault
green-m/c breaker is open m/c has no load yet
this is standard practice in hydro power station
 
It is simple to separate the RED=Live/Energised concept for power stations to RED=Stopped for process control.

For Process control, the process status is best represented by RED=STOPPED & Green = Running.

For Breakers and power distribution status, the status is best represented by RED=LIVE/Energised, GREEN=Dead/De-energised.

The 2 situations are very different.
 
Suggestion: When it comes to circuit breakers and switches, the indication lights have a heavy competition in Open and Close indications of the device status. I see that the light indication has to become more standardized and harmonized to catch up with the wording Open and Close so that it becomes more widespread.
 
I have worked in the hydro area and other industries. Hydro tends to use indicators backwards in my opinion (see I worked in other "industries" before hydro) but I am not an operator. If the operators understand it, I am okay with it I just have to remember it. The lights are such, in my opinion, because most operators are surrounded by electricians. Red means do not go in there, Green means you can. From the operators stand point green should mean yes its on and everything is okay. Anyway, its clear there is arguments from both sides it just depends on who is viewing the lamps. I think most people associate green with go and red with stop. If the world ever harmonizes then maybe this will be resolved once and for all but I doubt it since each industry requires special attention.
 
My apology to pinnpoint for causing him to feel defensive.(Sept 12) Such was not my intent but reading my thread I can see how it could have been intrepreted as such. Regardless of what everyone feels should be used it would be wise to measure the industry "known" in which your making the application. This is not a stead fast "hold on to tradition" philosophy. It is purely ecomomical. For my industry(Nuclear power and electric power in general) The color schematics are as I have previously stated. To change them purely at will or because your engineering 101 course professor seems to disagree would be monumental in terms of cost. By the way. Green does not mean GO. Green means that it is SAFE to go. (Traffic school 101). Again Red is energized. Red indication does not necessarily
imply that a system or valve or motor is unsafe. Rather it implys that the greatest potential for error or safety degradation lies within a system that is energized, open, running, etc. This is where the pressure and the flows are in a dynamic state. The greatest potential cause for a traffic accident lies with the person who runs the red light. Each industry seems to have a traditional standard. This is just one industry standard. And change just for the sake of change can be expensive. Human factors is built on experience. There are many bright new engineers entering many industries. Most lack the practical experience that has helped bring human factors engineering to where it is today. Don't attempt to erase that which has evolved over time for a purpose in your particular industry. There are many companies manufacturing in third world countries. And many American standards are being comproimised due to this. There is a reason these countries are "Third world". Why should we in America lower our tested standards for their sakes. Since when does number one slow down in a race just so every one else can catch up? When in Rome..... But when in America then...... Now I am getting condensending again. Geeze all this over a couple of lights!!!
 
Comment on the previous posting: There appears to be some trend in the industry standards convergence, e.g. UL, ANSI, IEEE, NEMA, etc. in USA tend to perceive IEC, EN, CE, etc. standards that becoming stronger with the global economy increasing, and the Earth staying with essentially the same dimensions.
 
here is another plot to make this soup even thicker.
look at a contact block (I have a furnas 64BB and 64BA)
The Green color is on the bottom of a N/O contact and the Red color is on the bottom of a N/C. A&B uses the same color also. Soooo by looking at this I would belive

Red = N/C = RUN or ON - normal position
Green = N/O = Stop or off - normal position

I am no expert only in this field for about 14 yrs.
I belive if you dont learn 1 thing new every day you wasted a day.

If I am wrong in theory please advise
 
But that's YOUR interpretation.

An equally plausible interpretation is that Green for NO is SAFE, while Red for NC is DANGER (perhaps because something is ON)

TTFN
 
More likely is
GREEN N/O is used for START buttons which are also green
RED N/C is used for STOP buttons (Fail Safe)which are also red.
 
exrpsd,

If you used the contacts in question as part of a typical two-button motor starter, you would find that the NO (green) is used as the start button, and the NC (red) is used as the stop button. Kinda spoils that theory!

 
In the UK and Europe the following is mandatory under BS EN60204-1

RED..emergency..eg value out of safe limits

Yellow...abnormal...eg value out of normal limits

Green....normal...make a guess

Blue...mandatory....eg instruction for operator to do something

White.....neutral....eg general information

hope this sheds some light

 
Has anyone noticed that the original poster hasn't logged in for six months.
 
He has probably realised that there is no unified standard for panel indicators, and is laughing at those of us who are still here arguing about it!
 
Some of them forget where they posted things or work on something else.
 
He needs to hit the Red button to turn on his PC... or is it the Green one? [pc3]

LOL!

I think this thread deserves the longest continuous activity award! [medal]



Quando Omni Flunkus Moritati

 
Comment: By the time this thread originator returns, the standards for indicating lights will be unified
Green for go
Red for stop
or something similar
 
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