Running air line into stainless boxes

Status
Not open for further replies.
masterinbama said:
Not that I know of. But watch your conduit fill when pulling tubing into conduit. I actually had a Contract NASA inspector ask me what % fill I had calculated.
Click to expand...
The OP question is regarding stainless boxes.

For raceways and cable tray...

300.8 Installation of Conductors with Other Systems. Raceways or cable trays containing electrical conductors shall not contain any pipe, tube, or equal for steam, water, air, gas, drainage, or any service other than electrical.
Click to expand...
 
NFPA 79

NFPA 79

He's correct.

NFPA 79 11.2.2.2- Pipelines, tubing, or devices (e.g., solenoid valves) for handling air, gases or liquids shall not belocated in enclosures or compartments containing electrical control equipment.
Exception #1 Equipment for cooling electronic devices
Exception #2 Piplines, tubing, or devices that are an integral part of listed equipment and separated by a suitable barrier.

Doesn't specify stainless enclosures. It seems to refer to all enclosures.
 
But then...

But then...

I have installed control panels which had regulated compressed air run to them to maintain a positive internal pressure with in them. THis was mainly to keep contaminents out of the enclosures.
 
krisinjersey said:
I have installed control panels which had regulated compressed air run to them to maintain a positive internal pressure with in them. THis was mainly to keep contaminents out of the enclosures.
Click to expand...

Or for a "Z" purge in a classified area.
 
krisinjersey said:
He's correct.

NFPA 79 11.2.2.2- Pipelines, tubing, or devices (e.g., solenoid valves) for handling air, gases or liquids shall not belocated in enclosures or compartments containing electrical control equipment.
Exception #1 Equipment for cooling electronic devices
Exception #2 Piplines, tubing, or devices that are an integral part of listed equipment and separated by a suitable barrier.

Doesn't specify stainless enclosures. It seems to refer to all enclosures.
Click to expand...
I do not believe this applies to enclosures containing, e.g. only solenoid valves. The requirement states you cannot have solenoid valves in an enclosure that contains electrical control equipment, which solenoids are not.
 
Last edited:
krisinjersey said:
I have installed control panels which had regulated compressed air run to them to maintain a positive internal pressure with in them. THis was mainly to keep contaminents out of the enclosures.
Click to expand...

I think the key word in NFPA79 for this kind of thing is "handling". I don't think this kind of thing can be considered handling.
 
krisinjersey said:
He's correct.

NFPA 79 11.2.2.2- Pipelines, tubing, or devices (e.g., solenoid valves) for handling air, gases or liquids shall not belocated in enclosures or compartments containing electrical control equipment.
Exception #1 Equipment for cooling electronic devices
Exception #2 Piplines, tubing, or devices that are an integral part of listed equipment and separated by a suitable barrier.

Doesn't specify stainless enclosures. It seems to refer to all enclosures.
Click to expand...

Smart $ said:
I do not believe this applies to enclosures containing, e.g. only solenoid valves. The requirement states you cannot have solenoid valves in an enclosure that contains electrical control equipment, which solenoids are not.
Click to expand...

I guess that depends on what the definition of electrical control equipment is. Is the soleniod a part of the control system? If you wired up everything but the solenoid coil it is not going to work very well.

I can understand keeping unnecessary items out of an enclosure that is primarily air equipment, or same for something that is primarily electrical equipment. At some point many systems must have interconnected components and it is not possible (in general, someone will shoot this theory down) to put the solenoid in one enclosure and the valve it operates in another.
 
3.3.23 Control Equipment. Operating elements, such as relays,
contactors, circuit breakers, switches, solenoids, brakes,
and similar types of components, intended to govern or perform
a given function in the operation, including measuring,
sensing, monitoring, protecting, and regulating of machinery.
Click to expand...

Given this definition in NFPA79 I would say it is clear that a solenoid valve is control equipment if it controls something on the machine (like a cylinder). Purge or pressurization lines definitely not since they serve no role in operating the machine itself.
 
petersonra said:
Given this definition in NFPA79 I would say it is clear that a solenoid valve is control equipment if it controls something on the machine (like a cylinder). Purge or pressurization lines definitely not since they serve no role in operating the machine itself.
Click to expand...
I don't disagree with the definition... because the term defined is Control Equipment, not Electrical Control Equipment. Solenoid valves are electro-mechanical devices in that they operate utilizing electrical phenomena but functional control of the valve itself is mechanical. That is, for the issue at hand, solenoid valves do not control electric.
 
Smart $ said:
I don't disagree with the definition... because the term defined is Control Equipment, not Electrical Control Equipment. Solenoid valves are electro-mechanical devices in that they operate utilizing electrical phenomena but functional control of the valve itself is mechanical. That is, for the issue at hand, solenoid valves do not control electric.
Click to expand...

Electrical control equipment is still control equipment.
 
petersonra said:
Electrical control equipment is still control equipment.
Click to expand...
I agree... but the converse is not true, which is my point: Not all control equipment is electrical control equipment.

The requirement for no foreign system is in regard to enclosures with electrical control equipment.

Solenoid valves are not electrical control equipment in that they do not control electric.
 
Status
Not open for further replies.
Top