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dhula
10-08-2009, 03:46 PM
Hi Everyone,

I'm trying to spec an intrinsically safe LED certified for use in a class 1 div 2 environment. I typically use Allen-Bradley 800H LEDs but since these are not certified intrinsically safe, so I can't use them.

In fact, why is it that an LED needs to be "intrinsically safe" anyway? Does a device not have to store energy to require certification? From my understanding, LEDs are a bit "grey" when determining whether they are considered simple devices or not (i.e. do not require IS cert.). Why is this?

I have found a couple different LEDs made by BEKA and RTK that are intrinsically safe, however they are only certified for operation at -20°C.

I require certification for use at -40°C.

Any help would be greatly appreciated!

Thanks!
Derek

wireguru
10-08-2009, 08:09 PM
i think the issue is, there is other circuitry in the pilot light besides the LED itself which could be an ignition source upon failure

justdavemamm
10-09-2009, 09:53 AM
We use MTL DAG-172 ( a Green LED in the DA-170 series of PB/LED's) for I.S. in Class I, Division 1 installation. They are rated -40 to to +60 C.

I'm at a loss as why you need/want I.S. for Class I, Division 2.

weressl
10-21-2009, 04:29 PM
Hi Everyone,

I'm trying to spec an intrinsically safe LED certified for use in a class 1 div 2 environment. I typically use Allen-Bradley 800H LEDs but since these are not certified intrinsically safe, so I can't use them.

In fact, why is it that an LED needs to be "intrinsically safe" anyway? Does a device not have to store energy to require certification? From my understanding, LEDs are a bit "grey" when determining whether they are considered simple devices or not (i.e. do not require IS cert.). Why is this?

I have found a couple different LEDs made by BEKA and RTK that are intrinsically safe, however they are only certified for operation at -20°C.

I require certification for use at -40°C.

Any help would be greatly appreciated!

Thanks!
Derek

In Cl. I, Div. 2 location intrinsicaly safe is an overkill.

There are numerous LED sourced lamps that are suitable and listed as Cl. I, Div. 2. A-B, Stahl/Killark, Crouse-Hinds, etc.

Intrinsic safety looks at the circuit parameters and components for enrgy storage and the power supply to determine if sufficient energy can be discharged in the case of arcing failure to ignite the specific material/oxygen mixture. It presumes dual failure. Division 2 certifications and tests consider a single failure.

petersonra
10-21-2009, 05:24 PM
Hi Everyone,

I'm trying to spec an intrinsically safe LED certified for use in a class 1 div 2 environment. I typically use Allen-Bradley 800H LEDs but since these are not certified intrinsically safe, so I can't use them.

In fact, why is it that an LED needs to be "intrinsically safe" anyway? Does a device not have to store energy to require certification? From my understanding, LEDs are a bit "grey" when determining whether they are considered simple devices or not (i.e. do not require IS cert.). Why is this?

I have found a couple different LEDs made by BEKA and RTK that are intrinsically safe, however they are only certified for operation at -20°C.

I require certification for use at -40°C.

Any help would be greatly appreciated!

Thanks!
Derek


1. I am not sure why an LED would not be a simple device. I have seen IS barrier data sheets that allow the use of generic LEDs, so presumably there would be no need for any special certification of the LED if it met the parameters of the IS barrier.

2. Div 2, as other posters mentioned, would not need IS with LED lights rated for Div 2.

3. The temperature rating you are dealing with is going to be tough to come to grips with. That is downright cold.

weressl
10-21-2009, 05:30 PM
3. The temperature rating you are dealing with is going to be tough to come to grips with. That is downright cold.

But LED's will LOVE it, the colder is the brighter they are.:)

petersonra
10-22-2009, 02:14 PM
But LED's will LOVE it, the colder is the brighter they are.:)

Getting UL to test and list it at those temperatures might be an expensive issue.

Did you know that -40C and -40F are the same temperature?

weressl
10-22-2009, 02:57 PM
Getting UL to test and list it at those temperatures might be an expensive issue.

Did you know that -40C and -40F are the same temperature?

The T-rating, in this case, concerns itself with the highest ambient temperature. the lowest(ambient) temperature would have no impact on the rating. but the functionality of the unit.