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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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When was the last time anyone saw a green emergency stop button?
 
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! :)
 
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!
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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.
 
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
 
"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?
 
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

 
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.
 
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
 
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.
 
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
 
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!
 
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
 
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.
 
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
 
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
 
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
 
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.
 
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.
 
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
 
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