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Standard Color for indicator lights
10

Standard Color for indicator lights

Standard Color for indicator lights

(OP)
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

RE: Standard Color for indicator lights

I don't know of an industry standard to reference but I've always seen and was taught that green is safe condition and red unsafe from a personnel safety viewpoint.  This then translates into for electrical:
green - circuit breaker, switch is open
red - circuit breaker, switch is closed
for mechanical (valves):
green - valve is closed
red - valve is open

wbd

RE: Standard Color for indicator lights

3

OP may want to review Thread248-39408.
  

RE: Standard Color for indicator lights

2
NFPA 79 covers this topic, as related to Industrial Machinery

RE: Standard Color for indicator lights

Red Star for you, jdbrandt.  I never knew 79 was in there.  Cool.

RE: Standard Color for indicator lights

I vote my star to busbar for a link that answers the question in details, including many standards.

RE: Standard Color for indicator lights

Oh yeah.  Guess I should have checked his thread.  Red Star for you too, bus.

RE: Standard Color for indicator lights

(OP)
Gentlemne,

Thank you.  Now I am as confused now as when I started this quest.

As stated so eloquently it is the users choice, and I will ask them  to decide.

The reason for the question is that there are three conflicting designs by vendors that are being integrated into a project.  2 Will have to change their designs to accomodate.  I was hoping that there was truly a standard to apply.  NFPA, I believe is quite ambiguous depending whether you are discussing Life Safety or Process Performance.

Well, Thanks again

William F. Moore

RE: Standard Color for indicator lights

wfmoore:

For what its worth:

I by no means would say we are politically correct, but for the petroleum sub-pump industry our typical lights are:

Green -- Running
Yellow -- Stopped, but auto restart pending, timer running
Red -- Failure that will not auto restart

It would be nice if the whole world was on the same page!  If you find some written standards please post them.

If you want some fun swap some lenses.   

RE: Standard Color for indicator lights

d23, I have seen this used as well in the oil industry. If the product is going overseas then there are standards for colors on that by the IEC. There are standards, it depends on your end application and location.

RE: Standard Color for indicator lights

In my background in pharmaceutical processing plants and other commercial/light industrial, red=run and green=stop.

It'd be nice if the whole world would follow that lead.

RE: Standard Color for indicator lights

peebee!

When was the last time you went through a red light (knowingly).
In my country (I suspect yours too) RED means "STOP" and GREEN means "GO". It would be a shame if we were to reverse the meaning of this symbols as you suggest, just so the pharmaceutial industry can advance themselves. Sounds selfserving to me (Just kidding).
Convention for me is; when the machine is off nothing is illuminated. If the machine is running (normal running condition) AMBER indicators maybe illuminated.
Upon a fault condition, the machine is shut down and RED indicator lights are illumated indicating the cause of the outage.
To use RED as a general indicator of operation, is a false indicator of operation.

What if you had to enter a very tightly closed room and you could only enter the room if the fresh air fan was running. Would you enter the room with a RED indicator light by the door or a GREEN light.

Regards
pennpoint


   
   

RE: Standard Color for indicator lights

Red = "Run" is very common in the US.  My guess is close to 50% of the installations here use Red = "Run" (the rest of the porr confused masses use Red = "stopped").

Good luck getting anyone here to standardize on light colors here.  Good luck getting anyone to standardize on digital cell phone standards, HDTV standards, or Mac vs. PC too while you're at it.

I agree that there's a saftey concern here, but both standards are very entrenched.  Even worse, as observed by wfmoore, "NFPA, I believe is quite ambiguous depending whether you are discussing Life Safety or Process Performance."  Now, THAT's entrenched.

RE: Standard Color for indicator lights

Why not create your own plant standard... purple and yellow so there's no chance of anyone getting confused due to remembering their old plant?

It's a thought.  Personally I would go with red means pump on...breaker closed....valve open.  That's what I've always seen.

RE: Standard Color for indicator lights

To pennpoint,

My experience is that red = energized = run is much more common in U.S. industrial facilities than the opposite.  I believe this practice stems from the use of red to indicate a closed breaker or energized bus in electric utility systems.  

If you accept that you will use red to indicate "energized", it's a little tough to decide green means running.  

I believe the Navy using red for running as well, but I could be wrong on that.

The red/green traffic light analogy is really a red (green?) herring.  

It's also interesting to note that building exit signs in the US can be either red --- or --- green.  

You must use whatever is standard in your facility.  The worst possible situation is not being consistent.

Despite whatever standards may be referenced, there is no single accepted standard in the US.  

I believe even OSHA acknowledges that this is a "local custom".   

RE: Standard Color for indicator lights

You can still add labels under the lights to avoid any confusion.

RE: Standard Color for indicator lights

2
Actually, if you take the Red = Dangerous, Green = Ready philosophy and forget Go and Stop issues, then even a traffic light follows.

Think about it:

Red does not mean Stop, since you may already have been stopped for some other reason. It really means "Danger: You will likely be killed or injured if you Go into (or stay in) this intersection!"

Green doesn't necessarily mean you MUST Go, it means "OK to do whatever you want to in that intersection, including stopping in the middle, smoking a cigaret etc., because it is safe for you as long as it is still Green (and the guy behind you does not have a gun)!"

Yellow of course then means "Warning, this intersection is about to become very dangerous for you!"

As far as I am concerned, this follows the vast majority of industrial color code logic.

If you do not agree with this interpretation, ask any police officer what you are expected to do if you are already in an intersection and the light goes from Yellow to Red: Do you STOP or do you get the hell out?

Quando Omni Flunkus Moritati

RE: Standard Color for indicator lights

By the way, I've now heard a couple times within the last year or so that more and more vendors are starting to use flash patterns rather than color to ensure colorblind people aren't confused by the green/red thing.

So, maybe the color doesn't even matter anymore.

Pennpoint, how's your compliance to the new flash standard?

RE: Standard Color for indicator lights

I don't understand how the flash approach descirbed would work in a complex control room. Flashing is used to identify things that need attention such as alarms, not valves whose normal position may be open or closed. Generally, color blind people are screened out of these jobs. Obviously there must be something I'm missing because I have never heard of the new flash philosophy or standard.

RE: Standard Color for indicator lights

Suggestion: The indicating lights shall follow the application standards or a proximity of application standards. Visit
http://www.fletc.gov/pro/ftc01-A04/specs/16410.pdf
for ATS indicating light standards taken from AIA specs Section 16410 Automatic Transfer Switches:
2.1.1.10 Indicating Lights
a. A green indicating light shall supervise the normal power source and shall have a nameplate
engraved NORMAL.
b. A red indicating light shall supervise the emergency power source and shall have a nameplate
engraved EMERGENCY.

The nameplates under the lights are enhancing safety when it comes to emergency systems and in general

RE: Standard Color for indicator lights

electricpete:

The flashing light idea was something I heard from a couple different vendors, back in December or so.  For me to call it a "standard" was perhaps misleading, sorry for any confusion.  I've not seen anything documented on this.

RE: Standard Color for indicator lights

Woffmore,

And to further muddy the colored waters, don't forget those afflicted with "color-blindness", especially the green-red kind!

Peebee, I hope it wasn't anything like the "bouncing-ball" fiasco that was used to increase traffic thru NYC's Holland-Tunnel, years ago!

RE: Standard Color for indicator lights

bouncing ball?

RE: Standard Color for indicator lights

Peebee,

The Port of NY/NJ Authority traffic-control guru's installed a number of strobe lights at predetermined distances the length of the tunnel.  The idea was for drivers to keep abreast of the "ball of light" as it "flashed" thru the tunnel, thereby maximizing the number of cars the tunnel could accomodate.

The problem... motorists were so intent on watching the bouncing "ball of light" that their driving skills were, well, for lack of a better term, ignored.  The result... a major increase in accident-rate!

RE: Standard Color for indicator lights

I'd imagine, sounds like the Pied Piper leading the lemmings into a giant mid-tunnel rear-ender pileup.

I'm kind of surprised no body went into a seizure or hypnosis with all the strobe lights going off.

When did this happen?

RE: Standard Color for indicator lights

My 2 cents.
Green is normal, stop or run. If it runs and green, it should be safe for people to work around it. If it stops and green everything is OK and ready to run.

Red is fault or bad, run or stop. It is dangerous condition. If it runs and red, do not cross or stick your hand in.  If it stops and red, call the field service guys.

Yellow is warning. Need filter change or low on oils.

Thx,

RE: Standard Color for indicator lights

dear sir
normally in all power plants which i work G.E &WESTINGHOUSE designs,green colour represent running condition and red is stopping condition,no especial standard is being created for that,but normally green colour is more visable from long distances than red.

RE: Standard Color for indicator lights

Peebee,

The 60's!

RE: Standard Color for indicator lights

Normally, in my experience with motors, amber indicates power available.  Green indicates run.  Red indicates trouble or fault.  If the motor is stopped, then only the amber light will be on.

RE: Standard Color for indicator lights

Suggestion: Visit AIA specification section 16480:
http://www.cleanrivers-pdx.org/pdf/16480.pdf
for: 2.9.3 MOTOR CONTROL - PILOT LIGHT
As indicated on the Drawings; provide RED “Motor On” and GREEN “Motor Off, Push-to-Test, transformer-type indicating lights on each starter.

RE: Standard Color for indicator lights

jbartos:

I would not challenge you or your referance, but this is the city of Portland.  Is Kansas City the same?

I'm glad that our PLC's can be programed!!!  You name it, we do it!

RE: Standard Color for indicator lights

for semi automatic machines

red: machine stopped .with fault
yellow: machine running
green: machine ready for part loading unloading
green/yellow: operator needs to push button to resume cycle

RE: Standard Color for indicator lights

why don't you try IEC/EN 60204-1
this tells you the colors for pilot lights

RE: Standard Color for indicator lights

jbartos, I agree with the AIA quote.  It scares me we're resorting to asking the architects though!!!

:)

RE: Standard Color for indicator lights

Suggestion to peebee: Sometimes, there is not much choice left, if the electrical engineer or designer is working for an architectural firm and things are pretty much set. One has to know who is the boss around.

RE: Standard Color for indicator lights

I thought the PM was the boss, and the archie just one more peer-level discipline. . . .

RE: Standard Color for indicator lights

I still vote with jbartos, with some minor adjustments and additions:
RED “Motor On” and GREEN “Motor Off, Ready. AMBER "Alarm"
This is the way I see it done in most industries. Look at pre=packaged accessories for motor starters from all of the major manufacturers. If you want a "Run" light it is red.

Quando Omni Flunkus Moritati

RE: Standard Color for indicator lights

Here are some more for contemplation...

ALTERNATING RED, GREEN, AMBER = "Jackpot!"
BLUE = "Duck and Cover!"
PURPLE = "Hide! The boss is looking for someone to blame!"
WHITE = "Virgin Operator"
MAUVE = "Redecorate"
ULTRAVIOLET = "Jimi Hendrix Alert"
SWIRLING MULTICOLORS = "Flashback to 1969"

Quando Omni Flunkus Moritati

RE: Standard Color for indicator lights


jraef -- In that vein, Lava Lamps never really got their just deserts in industrial annunciation.
  

RE: Standard Color for indicator lights

Too true. Cool idea actually.

We are all so stuck on stodgy practicality that we leave no room for the whimsical in industrial practices.

I vote for the Willy Wonka approach to equipment status indication.

Quando Omni Flunkus Moritati

RE: Standard Color for indicator lights

When was the last time anyone saw a green emergency stop button?

RE: Standard Color for indicator lights

jraef

I submitted your color scheme in the company suggestion box.  I even included BUSBAR’s lava lamp as a possible replacement for a strobe light system.

Sure glad I signed the managers name on that one!

RE: Standard Color for indicator lights

Suggestion to d23 (Petroleum) Mar 11, 2003 marked ///\\\
jbartos:

I would not challenge you or your referance, but this is the city of Portland.  Is Kansas City the same?
///Yes Sir. The AIA specs are pretty much the standard throughout the A/E industry in US and possibly abroad.\\\

I'm glad that our PLC's can be programed!!!  You name it, we do it!  
///Impressive\\\

RE: Standard Color for indicator lights

Flashing lights can also be used to convey a message.

GM - Check Engine Light  # of Flashes = error code
Allen Bradley - Device-net # of Flashes = error code
Cutler-Hammer - Flashing Run Indicator = Reset network node

All Three examples are the same type of network signal that the maint/operator can see and report back to the control room person on the HIM.

RE: Standard Color for indicator lights

Hi wfmoore
I was feeling left out of agood discussion,so here goes my 3 cents.
Of all the plants I have worked in North America all hi-voltage switchgear used the "RED" for run and "GREEN" for
open.For anything under 750 volts,it seemed that the Standard was no Standard.Some used RED for "Closed" others used GREEN.

GusD

RE: Standard Color for indicator lights

"wired1 (Electrical) Mar 14, 2003
When was the last time anyone saw a green emergency stop button? "

I think this is a great point.  How would you have red as the color for emergency stop and for running?  What are peoples experiences with equipment that uses red for running?  Do they also use red for the emergency stop button?

RE: Standard Color for indicator lights

Color Coding for pushbuttons, indicator (pilot) lights, and illuminated pushbuttons

( NFPA 79 Industrial Machinery)
 
Color Device Type Typical Function Examples

RED

 Pushbutton Emergency Stop, Stop, Off Emergency Stop button, Master Stop button, Stop of one or more motors.
      
Pilot Light Danger or alarm, abnormal condition requiring immediate attention.  Indication that a protective device has stopped the machine, e.g. overload.
      
Illuminated Pushbutton  Machine stalled because of overload, etc. (the color RED for the emergency stop actuator shall not depend on the illumination of its light).


 
YELLOW (AMBER)

 Pushbutton Return, Emergency Return, Intervention - suppress abnormal conditions. Return of machine elements to safe position, override other functions previously selected. Avoid unwanted changes.  
      
Pilot Light Attention, caution/marginal condition. Change or impending change of conditions. Automatic cycle or motors running; some value (pressure, temperature) is approaching its permissable limit. Ground fault indication. Overload that is permitted for a limited time.
      
Illuminated Pushbutton Attention or caution/Start of an operation intended to avoid dangerous conditions. Some value (pressure, temperature) is approaching its permissable limit; pressing button to override other functions previously selected.

GREEN

 Pushbutton Start-On General or machine start; start of cycle or partial sequence
      
Pilot Light Machine Ready; Safety Indication of safe condition or authorization to proceed. Machine ready for operation with all conditions nornal or cycle complete and machine ready to be restarted.
      
Illuminated Pushbutton Machine or Unit ready for operation/Start or On Start or On after authorization by lights; start of one or more motors for auxiliary functions; start or energization of machine elements.


 
BLACK

 Pushbutton No specific function assigned Shall be permitted to be used for any function except for buttons with the sole function of Stop or Off; inching or jogging.


 
WHITE or CLEAR

 Pushbutton Any function not covered by thee above. Control or auxiliary function not directly related to the working cycles.
      
Pilot Light Normal Condition Confirmation Normal pressure, temperature.
      
Illuminated Pushbutton Confirmation that a circuit has been energized or function or movement of the machine has been started/Start On, or any preselection of a function Energizing of auxiliary function or circuit not related to the working cycle; start or preselection of direction of feed motion or speeds.


 
BLUE or GRAY

 Pushbutton Any function not covered by the above colors  
      
Pilot Light Any function not covered by the above colors  
      
Illuminated Pushbutton Any function not covered by the above colors
 

RE: Standard Color for indicator lights

Don't forget the IEC EN60204 electrical code. The NFPA has been morphing in this direction in the latest two issues in order to have agreeable international specs.  Thankfully, they match very closely.  The only thing to think about is our Amber versus their Yellow and their prevelance of Clear PLs and Black PBs.

RE: Standard Color for indicator lights

After I read all the different opinions of this case, I want to add just one more:

Red light: Power on, ready to start, stopped.
Green Light: Power on, started and running at normal condition.
Amber/Yellow light: Overload condition.

All refer to starters of motors.

Alfredo Corona
Mexico

RE: Standard Color for indicator lights

Corona? Great last name!
Red should denote danger or a fault condition.  I can understand red as a running indicator in that it implies a possible dangerous condition but times have changed.  In newer machinery, there should already be adequate guarding/protection to meet OSHA and EU specs. In the past red would be an excellent choice since the equipment was not fully guarded and not as safe to the user in general.

RE: Standard Color for indicator lights

For what it’s worth

We do really economical (cheap) twin pump float operated panels that use red = running, amber = tripped and higher quality water industry panels that use green = running, amber = tripped or fault and red = dangerous (normally e stop operated)

All applies to the UK

Mike

RE: Standard Color for indicator lights

This problem arises between US and European conventions. In Europe red is danger or stopped because of a fault . In the US, red is running. I have worked on two control panels to be installed on a North Sea oil rig one control panel built in the US the other in the UK. The UK control panel had red for fault indicators, the US control panel red for running! If this was not a recipe for an accident to happen – nothing is!

RE: Standard Color for indicator lights

Maybe a little off the first question...

Doesn't matter what the color of the light is, make sure (with sufficient meter) that the power is off and the circuit safe before working on it.....

RCC

RE: Standard Color for indicator lights

The trouble is that it is not the maintenance engineer with his meter who has the problem,it is the less skilled operator who gets muddled up with the indicators and thinks that the cooling pumps are running when in fact they are stopped on a fault.

RE: Standard Color for indicator lights

Indicator color is only one aspect of human factors engineering.  

We recently experienced a situation where the designer decided that a certain function would be really usefull if included in the user interface.  Any indeed, it's very useful.  BUT, he didn't carry it to the logical conclusion, and while if everything is working properly, it's fine, but if something is not working, there is no indication of a problem and the operator can be easily misled for a brief time into thinking that he's exercising the function, when it fact, the function has completely failed.

TTFN

RE: Standard Color for indicator lights

Suggestion: Please, notice that certain indicating light functions are industry standards and also safety related standards, e.g. NFPA 110-2002 Standard for Emergency and Standby Power Systems

RE: Standard Color for indicator lights

To all;
Monitoring this thread, it illiterates to me the need for more standardization. All contributors to this thread have  some merit.
Safety should be the main focus however. What I see is a majority opinion that, and I do paraphrase to a degree to support my view.
1.. GREEN: the system START button (illuminated or NOT) indicates system is ready to be started or is running normal,  START or GO button once pressed is illuminated Green.
2.. RED: The system STOP button as well as a EPO button if specified. Once pressed the system is OFF. Nothing is illuminated unless the EPO button has been iniated and is illuminated and/or any other alarm status indicator.  
3.. RED is also used as an “alarm status indicator” and the red indicator color should only be used to define specific alarm conditions (system running or shut down). These alarm status indications can be; LOW SUCTION PRESSURE, HIGH DISCHARGE PRESSURE, HIGH TEMPERATURE, LOW TEMPERATURE, LOW FLUID LEVEL, etc…You name the condition that you want to use to protect the overall system.
3.. AMBER: All secondary systems are operating normal ie; “HEAT”, “COOL”, BYPASS, HUMIDITY, INJECTION, (you name it); indicating to the operator that the system or sub systems are functioning (cycling on/off or porportionaly) as designed or as required by the system.
 
Why design a piece of equipment that indicates red (alarm) lights for a normal operating condition? I feel those that do this are giving a confused message of CAUTION and ALARM  instead of the true status of the operating equipment, therefore exposing them to possible harm and ourselves to  litigation.
Finally, I have to admit, my automatic coffee maker which I set every night so I can have a fresh brew in the morning has red lights to indicate the damn thing is "ON" program mode.
I lie awake at night worrying.

pennpoint    

RE: Standard Color for indicator lights

pennpoint,

Your last post seems to indicate that you recommend red indicate both "system running or shut down" (from point 3) and that green also be used to indicate system "started or is running normal" (from point 1).  Um, I'm still confused.

RE: Standard Color for indicator lights

I am involved in the material handling industry and would agree with penpoint. You look at a typical Start/Stop pushbutton and you see Green for Start and red for Stop. We take this further and illuminate the Start PBs to indicate the motor is running when pressed (started). As far as flow diagrams go, we use Green to indicate the position of 2 way valves, valves or gates open, or generally any flow indication. Red is used for High level, Hot bearing indication, Belt side slip indication or any other cause for concern or stoppage. Yellow is indicating a low level, or conditions that require attention but do not effect safety or immediate concern.
It is truly amasing how different diciplines can have such entirely different approaches to the same idea based on equipment operation.    

RE: Standard Color for indicator lights

I think that it goes to show how difficult it is to make binary decisions.  Another case in point, I have a portable disk running on USB.  It has a red/green combo indicator.  Red shows up when the power is applied and green shows up when there is disk activity.  

BUT, the most useful information that I could possibly want is NEVER display, e.g., can I disconnect it from the computer without losing data?

Someone thought that he provided useful information to the user, when in fact, the one critical piece of information is totally hidden.

Bottom line, it's impossible to use only two colors to indicate the myriad of information you want to display.  That's where good signage comes in.  

TTFN

RE: Standard Color for indicator lights

peebee:
Sorry if I continue to confuse you and others. I reread my post and see where someone could be further confused. It was somehow clear to me when I posted. Its the nuance thats lacking here, and without immediate responce and play the subject at hand suffers.

Ill differ to wiser people

pennpoint
  

RE: Standard Color for indicator lights

I think we should close this thread!

RE: Standard Color for indicator lights

I agree. Lets put up a red light icon to show that it is closed...

Or would it be an amber light?

Quando Omni Flunkus Moritati

RE: Standard Color for indicator lights

red, green, amber or

RE: Standard Color for indicator lights

Suggestion: It appears that vfmoore, original posting, his/her last posting indicated that "Now I am as confused now as when I started this quest." The NFPA standards/codes were addressed. If there are any ambiguities in NFPA Codes/Standards, then they can be submitted to NFPA for interpretations. vfmoore might keep the Forum posted.

RE: Standard Color for indicator lights

Sorry for jumping in so late here, I just joined.  Navy uses green for motor running, blue and yellow for circuit breaker open or closed.

ASTM F 1166 section 9.19 has color coding for indicator lights.

I'm looking at a picture of a ship's control console and the only red lights are alarm lights and emergency stop buttons.  If there is an illuminated "stop" button (for a pump) or "close" button (for a valve) it is white.

RE: Standard Color for indicator lights

The navy also has control rooms that need to operate in low light conditions, i.e. red illumination. Red lights then don't show up as well and can be mistaken for reflections of the luminaires....

"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams

RE: Standard Color for indicator lights

Most of my working life has been in the electrical power industry. From Fossil fuel powered plants including gas turbines as well as Nuclear Plant Control rooms. I have always known RED as 'energized', 'running', 'on', and 'open ( when referring to valves)'  Green the opposite of all the above. I suppose it depends on what industry you are working in. This was our standard.  

RE: Standard Color for indicator lights

Obviously colors are determined by the industry, at least in the US. At our hydro plant Red means energized and green means not energized. As I said before, the oil field equipment it was the opposite.

RE: Standard Color for indicator lights

On 5/6 pennpoint gave opinion on stutus lights. It is interesting to note the differring thoughts on this between an electrical engineer and a mechanical and a X Navy person.  What you all need to do is take the engineer mentality out of your thought process and consider the human factors. You cannot have Green as both "ready for start" and "running". This is a contradiction. Accepted standard for a closed or energized breaker is RED. If the pump associated with this energized breaker is running( as it should be) then it too should be 'red'. So than should the valves associated with the system to which the pump serves. It was very helpful whenever a nuclear plant trip occured to look over the board and see a system as either all red or all green ("sea of green"). If automatic actions required a system to be running you knew very quickly if it was not. I do not mean to be contrary but Pennpoints' logic is not logical at all. Under stress you want all apples or all limes but not a mixture of both. RED demands your attention, it implies that certain dynamics are involved. Green implys "safe".  You'll never get a ticket for running a green light.  The NAVY uses differing colors than that of the commercial  industries for one reason. When a ship goes to 'battle ready conditions' the battle room and con overhead lighting goes to red. This makes red indicating lamps not practical. Another human factors consideration. So lets keep the navy seperate as their needs are such.  

RE: Standard Color for indicator lights

Most of my working life has been in the United Kingdom electrical Steel / Utilities industries.  I have always known RED as  'Running'and Green as 'Stopped'. Has someone else said before i have "never" seen a green Emergency Stop Pushbutton.

RE: Standard Color for indicator lights

This is certainly a contentious point.  Industries dont even standardise.  Try the water industry where different neighbouring authorities/companies use different standards.

Can't a physical switch be used?  However, people would then argue whether it was up/down or left/right.

Why not have the text on the lamp i.e. RUN/STOP/FAIL and then you dont have to worry about colours, just dyslexic operators.

RE: Standard Color for indicator lights

I can assure you that in the power industry it is as follows:
         Red-running
         Green-available,off,standby
         Yellow-disagreement,failed to move or start
         White-lockout


Ravenjoe

RE: Standard Color for indicator lights

Suggestion: Visit
http://www.pauldavisautomation.com/safetyman.html
for:
There is no specific standard in the U.S. regarding stack lights. However, ANSI under B11.19 section E4.3.2.2.1 states "Due to lamp failure, visual awareness devices should use multiple lamps such as green for run and red for unsafe." What the exact meaning is of those colors on a stack light should be part of the documented operator and maintenance personnel training for that machine.

RE: Standard Color for indicator lights

cerpico et al;
Back tracking and reading my input over again I find myself in a defensive position here. My point is and has always been GREEN means GO, RED means STOP/WARNING (or an indication why the machine stopped).
The company to which I am employed, design and build verious testing facilities. Not process equipment. These are usually small sized (up to 4000lbs) equipments most are simi-portable. Not paper mills, mill hammers, steel mills, or etc..
My point was and continues to be: Indication of operation should give the operator some since of the degree of safety.
That is to say if you use RED indicator lights to show that the machine and all it's sub-circuits are operating normal you are giving that operator a false warning indication. If you do this, I believe this is old school philosophy.
//It appears most (not all) everyone this thread agrees that RED is STOP/WARNING\\
OSHA has lists of colors to be used as levels of HAZARDS:
Green:  Safe
Orange: WARNING
Red: DANGER
Blue: INFORMATIONAL
others:
I use GREEN as a Start button. Red as a STOP button. (normally neither are illuminated). There may be a "HEAT", "COOL", "HUMIDIFY" or more switch(es). Those functions when "ON" would be shown energized with a AMBER indicator. Amber because it can be seen and are not a hazard when functioning or not. They are just to let the operator know that they or working (fuctional/cycled) to the process.  You could tell me to use green and I would.
Auto-Shut down; Here, I use RED again only as an indicator to the operator as to: "LOOK" the machine stopped (automatically) approach with caution, find out why. Call your supervisor. The machine can be stopped by "E" stop, temperature, pressure or other harmful limits to its self or to personnel.
In my instance when I say the machine is "OFF" it's off (no auto restart). Only the temperature displays and chart recorder is energized to show the operator where things are or were in the process when it went down.

Cerpico; You yourself elude to the premis Green is GO, RED is stop.
I am saying the samething!!
I guess it comes down to this. If the machine is operating as it is designed, is safe or not. I say yes! and there should be no RED indicator lights lit if all is operating normal. If I approched a machine and  pressed the "START" button and the panel lit up RED! I'd run like hell to get out of there. Ya see..
In the "ole" days, (Hey I'm an old guy),  I remember the large red bullet nosed indicator panel lights. But these were on open frame, uncaged, unshrouded systems. Workers had to approach these machines with fear in their hearts.
When you start your car there should be no red light showing on the dash, or you'll be calling AAA.  
We as a "modern" industrialized nation of standards have come far and away from that. Just because a piece of equipment is "ON" does not mean it's unsafe, nor should we as engineers do what was done fifty years ago.   
I see no flaw in this logic, as you seem to do. I do see lack in the communicaton of our thoughts. Maybe your not totally wrong and maybe Iam not totally right, but I think we can meet somewhere in between.  

I hope this clears up any confusion from what I have posted in the past. This is my philosophy.
What is obvious here is that there is no real clear standard (now) that we ALL can follow except that we all must try to do the very best we can to address, protect and annunciate the safe operational status to those operators of our individual equipments.

Iam still worried about my coffee maker, is that really a warning light or not?

I wish you all well
pennpoint
  

RE: Standard Color for indicator lights

It's probably wise to remember that the way you've been trained is not necessarily the way other people would think.
Show Joe Average in the street a box with a red button and a green button and ask him which is start and which is stop.
My guess is that most people will go green for go, red for stop.

Same with indicator lamps.

If you are happy that the people who come into contact with the indicator lamp will be educated to know what it means, then fair enough, but if I build a machine here and give it to the workforce then I'd always go for green is go, red is stopped. And I'm a trained electrician so I know that in that trade we use red for on green for isolated...

I though us "engineers" were supposed to be logical!

Alternatively why not throw a spanner in the works and do like Disaster Area's stunt ship:

Zaphod Beeblebrox: "It's weird. Every time I operate one of these weird black controls, that are labelled in black, on a black background, a little black light lights up black to let me know I've done it."

"I love deadlines. I love the whooshing noise they make as they go past." Douglas Adams

RE: Standard Color for indicator lights

Suggestion: It appears that the international standards harmonization will resolve this green versus red dilemma.

RE: Standard Color for indicator lights

Yeah, that's what they said about the metric system too.

RE: Standard Color for indicator lights

I have seen and programmed SCADA both RED as running/Open and Green as Running/Open.

I must say, RED as Energised, which is supposed to be the international standard, is very confusing to both myself and the operators.

A stop button is always RED. Not to warn you away from it, but to mean STOP. RED means STOP, no matter what the international standards say. It is convention. It is in our culture, everyone knows it. To try and confuse this is wrong.

For the same reason, Start buttons are Always Green. By the international standar, shouldn't it be RED, to warn you that if you press it it will cause a dangerous situation.
NO, because that would confuse people.


This is why there is no standard that everyone uses. Because the internation standard conflicts with what everybody knows to be "The Right Way" to do it.

In the end, the customer gets what they want, but if it is my choice, I will say stuff the international standard. It is clearly wrong. It is more important to convey a message that everone understands, Not try to make everyone understand a backward standard.

Thats my opinion, and I will stick with it.

RE: Standard Color for indicator lights

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.

RE: Standard Color for indicator lights

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

RE: Standard Color for indicator lights

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.

RE: Standard Color for indicator lights

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.

RE: Standard Color for indicator lights

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.

RE: Standard Color for indicator lights

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!!!

RE: Standard Color for indicator 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.

RE: Standard Color for indicator lights

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

RE: Standard Color for indicator lights

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

RE: Standard Color for indicator lights

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.

RE: Standard Color for indicator lights

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!

RE: Standard Color for indicator lights

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

RE: Standard Color for indicator lights

Has anyone noticed that the original poster hasn't logged in for six months.

RE: Standard Color for indicator lights

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!

RE: Standard Color for indicator lights

Some of them forget where they posted things or work on something else.

RE: Standard Color for indicator lights

He needs to hit the Red button to turn on his PC... or is it the Green one?

LOL!

I think this thread deserves the longest continuous activity award!

Quando Omni Flunkus Moritati

RE: Standard Color for indicator lights

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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