Red for on or green for on

[Lancie1]

As late as 25 years ago, there were standards, both NEMA and JIC (Joint Industrial Concil). I still have a copy of it somewhere. It did call for Red as Energized, and Green as Safe, Yellow was Danger. This is a very old standard, and many of you have never heard of it, and can't understand how it got started.

It started with the fact that originally the colors that could be put on lights (and be visible), were limited. Early designers thought as if they were the pedestrian on the sidewalk, waiting to cross (Red = Go, Green = Stop). The early motor control centers used red lights to mean that the contactor was energized. If you find a very old MCC, it may have red lights that come on when the starters are energized. Since red was preempted for energized, that left green to mean "Safe". If you designed according to NEMA standards, you HAD to use these colors. That is why there is so much confusion today.

At some point, the standard-writers realized they were fighting a losing battle, because almost all operators thought as if they were a passenger in a car, not the pedestrian on the sidewalk. If you are the pedestrian, then Green does mean that it is no longer safe to stick your body into the path of the moving equipment, whereas Red means it is safe to proceed.

I wonder if in countries where they still do walk sometimes, if people still think the opposite?

 

[curlyandshemp]

Look at most PLCs regardless of make ,

CPU RUN LED RED = BAD , stopped

CPU RUN LED GREEN = GOOD , running

unless of course you use the theory that CPU Run LED = Red, stopped, therefore , safe to download,

CPU LED = Green, Running Unsafe to download

Ian

 

[monkeyhead]

So it comes down to one of two perspectives:

1. The state of the machine
2. The state of the operator

My operation uses the perspective of state of the machine. Green is normal running, red is fault, and blue/amber are warnings or minor faults. As far as I know, NFPA 79 here in the U.S. states this standard, so I follow it (correct me if I'm wrong). I'd honestly change any machine that didn't, because it would contradict every other machine in our plant.

 

[OkiePC]

Ok....Did I read the thread to fast? who voted other?

Me too, we use Amber for "AUTO", white or blue for "MANUAL", reset (power on) is red, blue or green depepnding on department and OEM. Our plant has no standards it seems...which my be beneficial. We know that if a lamp is lit at all, control power is present at least at some level. LOTO for true safety...

PC

 

[Ken Moore]

We are slowly doing away with panel lamps, almost everything is on an HMI now.

We have a plant wide standard on colors, so that operators from different areas can fill in with out re-learning the color codes.
We use:

In Auto and on: light green
In Auto and off: gray
In manual and on: yellow
In manual and off: dark blue
Unacknowledged alarm or fault: flashing red
Acknowledged alarm or fault: red
In maintenance mode (disabled): magenta

 

[Lancie1]

I did find a copy of the old NEMA standard. It is called "NEMA ICS-5-1983, Industrial Control and Systems, Control Circuits and Pilot Devices". (the last number, 1983, was the year of release.

I know that the colors of the pilot lights have been removed from later versions of this standard, simply because about 50% of designers were ignoring the standard because everybody knows "green means go". Sometimes the people are "wrong" but eventually become right by simple perserverance.

 

[Lancie1]

Yes, I was correct. In the latest NEMA (National Electrical Manufacturers Association)standard, "ICS-5-2000, Part 5, Pushbuttons, Selector Switches, Indicating Lights, and Pushbutton Stations", all references, that were in the older ICS-5 standard about the colors of indicating lights, have been deleted.

Your on your own here. Use good judgement!

 

[Mark_H]

I like a Green Lighted push button, that lights up when the system is "ON", and a Red Lighted Push-Pull Button, that Lights up when the system is "Off". The Red light in the Stop push button, serves as an indicator that the system is powered up, (Not a guarantee that the power is off), but is not started yet.

 

[just_lionel]

I wish someone would come out with a standard, if you want bizzare try my current place. A buzzer goes off together with a flashing orange lamp to warn of start-up, a blue lamp comes on with a fault. Unless its a pick up point where the conveyor only starts when there's something to deliver onto it, it flashes orange all the time its enabled.

We have a couple of places where green lamps are, F..k knows what their for?

The system you talk about seems perfect sense really, except red would normally be for fault.


Another question on lamps, each emergency stop and safety device we have has a lamp next to it, which when the device is operated the lamp goes on. This is a massive conveyor hall with E-Stops dotted around everywhere.

I would prefer the lamp always on, off when operated, this way if the lamp fails you will see it, not find out after you've been looking for a damned E-Stop for hours.

Sounds just like the Cooking Process machine we have at the plant I am in now. Crazy stuff.

 

[Binaural]

We are slowly doing away with panel lamps, almost everything is on an HMI now.

We have a plant wide standard on colors, so that operators from different areas can fill in with out re-learning the color codes.
We use:

In Auto and on: light green
In Auto and off: gray [we also use white]
In manual and on: yellow [we use a yellow device highlight]
In manual and off: dark blue
Unacknowledged alarm or fault: flashing red
Acknowledged alarm or fault: red
In maintenance mode (disabled): magenta

Apart from the exceptions I have noted in red above, we use similar conventions for our SCADA and HMI panels (we use very few pushbuttons these days either).

 

[jraef]

Originally Posted by PeterW
I wish someone would come out with a standard...

As posted by lancie1, there was a standard...

I like a Green Lighted push button, that lights up when the system is "ON", and a Red Lighted Push-Pull Button, that Lights up when the system is "Off". The Red light in the Stop push button, serves as an indicator that the system is powered up, (Not a guarantee that the power is off), but is not started yet.

... but this is an example of why we no longer have one. Nobody bothered to teach it / learn it so they made up their own based on "what I like".

 

[Lancie1]

There is a standard for this - for us Europeans anyway, standards for actuator and indicator light colours (and just about everything else to do with machine wiring) are covered in:

EN60204-1:2006 'Safety of Machinery - Electrical equipment of machines - Part 1: General requirements'

I've scanned in a couple of pages covering actuator and indicator light colours - I don't want to post it here for obvious reasons....

PM me if you want a copy....

Kevin, I could use a copy, but for now, could you just tell us what color (EDIT: excuse me, I mean colour!) is supposed to be used for a "motor running" indicator light in Europe?

 

[krk]

Lancie,

As usual in our Euro-specs, it's always open somewhat to individual interpretation, but I'd read it as GREEN or WHITE could be used for a motor running condition but definitely not RED or YELLOW as these are used to denote a machine hazardous or abnormal condition respectively.

Kevin

 

[Mark_H]

As posted by lancie1, there was a standard...


... but this is an example of why we no longer have one. Nobody bothered to teach it / learn it so they made up their own based on "what I like".

That is right. I would not of done it a way I did not like. Some folks are not happy untill someone gives them the answer.

 

[patriot]

In the printing industry, A green light means a press is "safe" to work on.


A red light means it's "running".

It took some getting used to when I first started working in this industry.