It was me that started the most recent thread on this.  Here are all the
responses I received, in no particular order: (separated by *********'s
).  Of course, for European approval purposes, IEC73 has the final say,
but it is as open to interpretation as any standard.  It is interesting
to note that there are two basically opposite interpretations in the
responses that follow!  The CB that I consulted said that the "as long
as it is clear that safety is not involved" part of the 950 requirement
means clear to the user so a label next to the LED explaining what it
means basically frees us up to use any colour we want.

My thanks to all who responded.

Regards,

Jim Eichner
Statpower Technologies Corporation
[email protected]
http://www.statpower.com
Any opinions expressed are those of my invisible friend, who really
exists.  Honest.  



******************
In keeping with my practice of making things simple here are my
thoughts:  

The presence of mains voltage at an approved mains socket outlet should
not 
involve a safety consideration - so the red led does NOT violate EN
60950.  

If you are challenged, continue to argue that what the end user will
connect to 
this socket outlet is not specified.  Some things left powered on could
involve 
safety.  Therefore, the red led is required.

Best Regards, Lou

*************************
FWIW ... 

About 10 years ago, I hired a lawyer who specialized 
in product liability for a 2 day seminar for engineers 
and marketing types. 

After alot of nit-picking, it was concluded that RED 
lamps or indicators weren't to be used for things 
that had anything to do with power. At the bottom of 
the argument was an ON/OFF switch which used a red 
lamp to indicate 'ON". His literal interpretation of 
the color RED be it in a lamp or even on a label was 
"Hands off", "Danger", etc ...  An indication of something bad. 

We changed over to a power switch with a Green lamp 
to indicate "ON". Since then, I have imposed green LEDs 
for switches, power modules, etc ... to indicate "ON", 
"Everything's OK", etc ...  An indication of something good. 

Red LEDs are used ONLY for alarm indicators (telco). 
***************************
Jim,

If the indicator must be on the dash board and I suspect your inverter
is not there, can't you just tap the indicator off the protected outlet
using a supplied accessory? That would keep your inverter compliant and
the indicator is available to those that need it.

Regards,
Scott
[email protected]


*****************************

Jim,

I have had a similar problem. In the end, TUV convinced me that since
the operator had no access, then the LED should not be red. Not
completely convinced, I added a label at the LED that said "circuit is
live when light is on".

In your case, what is the 230 VAC provided for? If there is something
specific connected to it (like a mechanism or heater or something) that
might injure an operator, then it might still be a safety function.

Regards,
Scott
[email protected]


**************************


Hello Jim,

I would believe here that the presence of a high voltage on an approved
outlet is no concern of safety.
You LED could only be interpreted as an on/off signal.

The presence of any approved shielding or isolating measure, inhibits
the "danger" aspect, and mans that safety is not involved.  

Any unshielded or accessible terminal could be considered as a dangerous
situation in which case the LED could mean "danger". (in your example
the color would be OK).

Regards,

Ing. Gert Gremmen


*********************** 
Jim and your trusty,        friend:
     May I shed a different light on this issue? As far as I can figure
out 
     your predicament, you want to indicate that ac power is available
at 
     the output outlet of the inverter - why not using a "neutral"
color, 
     e.g. blue, orange or white? 
     I always interpreted the illumination of a red indicator as saying 
     "Danger!" with whatever interpretation you want to attach to
"Danger", 
     but the red light - in my opinion - should never come on as the
result 
     of a switch action, except when the electronics/control or the
insides 
     of the equipment is busted, can not be placed into an operating 
     condition, and when this red light is disregarded, some harm may 
     result. 
     I hope that this makes you look at you problem somewhat "sideways",

     because the standard answers may not always fit the bill.
     Regards,
     Bogdan.
     [email protected] 

**********************

Over the years the use of a red LED has been discouraged for use on
products because "Red" was reserved for situations "hazardous to an
operator". This resulted in the elimination of Red LEDs from keyboards
and other devices. Clause 1.7.8.2 of EN 60950 specifically allows Red
LEDs in areas where safety is not involved. As such I see no problem
using the device in conjunction with a user operated switch. I think
that was the intent of "permitting" red LEDs. Another point is that a
Red LED is much different than the use of a Red indicator light.

Regarding my last posting on shielded cables not being allowed in
Europe. I was misinformed. Apparently there are no longer any rules to
this effect. The beauty of this discussion group is that I learn
something every day.

Rick
[email protected]

***********************

Jim,

If it turn out that you need both colors, consider a two color LED and a
jumper (or cutable trace) on the circuit board so you get either yellow
or
red; at least you don't have to spec-in two different LEDs.  For what
it's
worth.

Eric

*******************



> -----Original Message-----
> From: MartinJP [SMTP:[email protected]]
> Sent: Tuesday, February 10, 1998 12:57 PM
> To:   [email protected]
> Subject:      Red LED's
> 
>      
>      All, 
>      
>      We are a manufacturer of laboratory equipment.  We currently
> evaluate 
>      our products to UL 3101-1, EN 61010-1, CSA 1010.1, EN55011 and EN
> 
>      50082-1.
>      
>      We use several LED's for indicators (including red for instrument
> 
>      failure) on the front of some of our products.
>      
>      I recall some postings on this forum which discussed the
> requirements 
>      for the use of red LED's.
>      
>      Unfortunately, I did not archive any of those postings.
>      
>      Can you please provide me with information on any requirements 
>      relating to the use of red LED's for laboratory equipment.
> Please 
>      include standard numbers in your references.
>      
>      Thanks for the help.
>      
>      Regards,
>      
>      Joe Martin
>      EMC/Product Safety Engineer
>      P.E. Applied Biosystems
>      [email protected] 
>      
>             

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