Connections inside Conduit

[fifty60]

I have some pressure switches that have leads too short to reach my sub panel. We run the conductors in a split-loom conduit (corrugated loom). I do not think the corrugated loom is technically considered conduit.

If I use a butt splice with shrink tubing for the lead connection to a longer conductor, is it ok to have the shrink tubbed butt-spliced connection hidden inside of the split loom? Or, do I have to expose any connections like that? I am interested at looking at this from an NEC or UL perspective.

 

[mgookin]

I have some pressure switches that have leads too short to reach my sub panel. We run the conductors in a split-loom conduit (corrugated loom). I do not think the corrugated loom is technically considered conduit.

If I use a butt splice with shrink tubing for the lead connection to a longer conductor, is it ok to have the shrink tubbed butt-spliced connection hidden inside of the split loom? Or, do I have to expose any connections like that? I am interested at looking at this from an NEC or UL perspective.

What's the voltage and power in this conductor?
What other voltages and power are in that loom?

I'm thinking a little j-box would be most appropriate. If there are problems in a conductor it's almost always at a connection.

As to specific UL requirements, it primarily just has to not electrocute somebody. Your "patch" would have to exceed that of the insulation.

 

[petersonra]

I have some pressure switches that have leads too short to reach my sub panel. We run the conductors in a split-loom conduit (corrugated loom). I do not think the corrugated loom is technically considered conduit.

If I use a butt splice with shrink tubing for the lead connection to a longer conductor, is it ok to have the shrink tubbed butt-spliced connection hidden inside of the split loom? Or, do I have to expose any connections like that? I am interested at looking at this from an NEC or UL perspective.

Split loom is not an acceptable way to run single conductors unless it is inside of an enclosure. It has to be a chapter 3 wiring method and I do not think split loom is in chapter 3.

If it is inside the enclosure it does not matter where you put the splice as long as it is accessible. Split loom would make it accessible IMO.

You asked a very similar question not real long ago.

http://forums.mikeholt.com/showthread.php?t=157529&highlight=split+loom

 

[fifty60]

These are 115V circuits. There is not much current involved, just enough to activate a relay. What voltage and current combination should I be concerned with enough to use a j-box? I know UL probably always requires a J-Box for motors and transformers...

 

[petersonra]

These are 115V circuits. There is not much current involved, just enough to activate a relay. What voltage and current combination should I be concerned with enough to use a j-box? I know UL probably always requires a J-Box for motors and transformers...

What do you mean by "UL"? There are a bazillion UL standards and they all have different requirements.

 

[GoldDigger]

These are 115V circuits. There is not much current involved, just enough to activate a relay. What voltage and current combination should I be concerned with enough to use a j-box? I know UL probably always requires a J-Box for motors and transformers...

IMHO if it is 115V but is not current limited to make it fit under a Class 2 or Class 3 circuit description, then Article 725 would apply the normal Article 300 wiring standards and not allow the flying splice in the first place.

 

[fifty60]

Thanks for referring me back to my old post Golddigger, it helped to read through it again. This question is slightly different though. We are testing to BS-EN61010 which is word for word UL-61010. So you think the NEC will only allow an un-spliced conductor?

 

[fifty60]

Article 725 seems to deal with components and wiriing remote to the equipment...the pressure switches in this situation are definitely inside of the equipment.

 

[petersonra]

Article 725 seems to deal with components and wiriing remote to the equipment...the pressure switches in this situation are definitely inside of the equipment.

the NEC does not generally apply to conductors or splices or anything else that are part of factory assemblies and UL listed.

"inside" of the equipment might not mean though that it is covered by your UL listing.

is this splice allowed by the UL spec you are building to and is the splice part of the equipment you are listing. the answer may or may not be real obvious.

usually a UL listed piece of equipment has a well defined boundary point - like the enclosure for a UL508a control panel. If it is inside that enclosure it is covered by UL508a. If it is outside that enclosure it is not.

 

[GoldDigger]

the NEC does not generally apply to conductors or splices or anything else that are part of factory assemblies and UL listed.

"inside" of the equipment might not mean though that it is covered by your UL listing.

is this splice allowed by the UL spec you are building to and is the splice part of the equipment you are listing. the answer may or may not be real obvious.

usually a UL listed piece of equipment has a well defined boundary point - like the enclosure for a UL508a control panel. If it is inside that enclosure it is covered by UL508a. If it is outside that enclosure it is not.

I have some pressure switches that have leads too short to reach my sub panel....

Article 725 seems to deal with components and wiriing remote to the equipment...the pressure switches in this situation are definitely inside of the equipment.

Well, the pressure switches are certainly not inside the sub panel.
Just what kind of space inside or on the surface of the machine being controlled contains the wire loom seems to be a relevant question. Having integral pressure switches sounds much more like a machine than an control panel, so what kind of machine is it and is it your intention to get UL listing for the whole finished assembly?
Or are you just trying to meet NEC standards for field wiring (which do not apply?) as a design guideline?
Simply complying with 725 will not necessarily get you UL approval for the whole.

 

[pjholguin]

Instead of hiding the splice, put the appropriate connectors at the pressure switch. Than when the devices needs to removed you have a quick disconnect and there are no hidden failure points.

PJHolguin

I have some pressure switches that have leads too short to reach my sub panel. We run the conductors in a split-loom conduit (corrugated loom). I do not think the corrugated loom is technically considered conduit.

If I use a butt splice with shrink tubing for the lead connection to a longer conductor, is it ok to have the shrink tubbed butt-spliced connection hidden inside of the split loom? Or, do I have to expose any connections like that? I am interested at looking at this from an NEC or UL perspective.

 

[fifty60]

That is exactly the rout I am trying to take. I would like to get only terminals and no leads for the switches...but it takes time and there is some inventory involved....

We make test equipment...the equipment ranges from 8, 16, 32, and 64 cubic foot. All of the wiring is integral to the equipment, and not accessible to the operator. The majority of our equipment has no markings, we occasionaly have customers request UL equipment, so we go through that process. We are trying to CE mark several product lines of our equipment...

I want to make sure that the practice is generally accepted, and then be able to back it up with references to NFPA 79, the NEC, etc. With CE you have a technical file where you are given some room to defend you positions and explain your reasoning...not in every case, but in some.

Its sooooo much easier and less labor to not have to install junction boxes, and just use the butt splices (reinforced with shrink tubing) inside of the split loom.

Along similar lines, i have questions about grounding and bonding. I know it is a vast subject and there is a lot of information available. Specifically my question is about joining grounds. Is it ok to join gounds together in a wire nut? i do not like the practice, but I want to find where it is allowed or prohibited...I've mentioned the 222 wago connectors previously. The Wago website says they are "approved for bonding and grounding"

Usually, we are required to run a seperate terminal bar and locate it in a junction box, I am wondering if the wago 222's are an acceptable replacement for installing the seperate ground bar...

 

[pjholguin]

My thought was to use a plug and jack connector(molex connector), I have seen this configuration on many systems within an equipment skid/enclosure.

PJHolguin

That is exactly the rout I am trying to take. I would like to get only terminals and no leads for the switches...but it takes time and there is some inventory involved....

We make test equipment...the equipment ranges from 8, 16, 32, and 64 cubic foot. All of the wiring is integral to the equipment, and not accessible to the operator. The majority of our equipment has no markings, we occasionaly have customers request UL equipment, so we go through that process. We are trying to CE mark several product lines of our equipment...

I want to make sure that the practice is generally accepted, and then be able to back it up with references to NFPA 79, the NEC, etc. With CE you have a technical file where you are given some room to defend you positions and explain your reasoning...not in every case, but in some.

Its sooooo much easier and less labor to not have to install junction boxes, and just use the butt splices (reinforced with shrink tubing) inside of the split loom.

 

[fifty60]

Is the main idea that the splices should not be hidden? or that they should be accessible?

Would these work in place of the Molex connectors?

http://www.wago.us/products/termina...-for-all-conductor-types-222-series/overview/

 

[pjholguin]

I have never seen that connector used before, but I would look for a connector that that is enclosed...meets IP67 requirements. You wouldn't want to H2O, Oils, or conductive particles to short circuit the connections.

PJHolguin

Is the main idea that the splices should not be hidden? or that they should be accessible?

Would these work in place of the Molex connectors?

http://www.wago.us/products/termina...-for-all-conductor-types-222-series/overview/

 

[fifty60]

The 222 connectors make a "gas tight" seal... The majority of the situation where I would use the 222's would be in a junction box. I think my best bet for the pressure switches is to get tab'd terminals, and until then use the butt splices with the shrink tubing as extra protection. But back to my original quesiton, is it acceptable that they are "hidden" inside of the split loom as long as they are accessible because of the split loom.

We have some other equipment that uses a different directive, and uses molex connectors. Everywhere they make a connection they also break the conduit (loom or flex tubing) so that the molex connector can be seen. I think it looks terrible. I would rather not have to do that with the split loom if possible.

 

[pjholguin]

Does it meet your equipment specification? If yes then run with it.

PJHolguin

Is the main idea that the splices should not be hidden? or that they should be accessible?

Would these work in place of the Molex connectors?

http://www.wago.us/products/termina...-for-all-conductor-types-222-series/overview/

 

[mgookin]

You now have 2 questions on the table:

1) If you have 120v in that conductor and you're going to make it safe using a heat shrinkable insulation, that insulation must be suitable for making safe 120v conductors. You'll need to prove this to UL using product data sheets.

2) Grounds are connected using wire nuts all the time, but in building wiring. If your equipment is subject to vibration, I'd go with a heavy duty crimp lug or a little ground bar. If you're not subject to vibration I think the wirenut should be fine for joining exposed conductors.

 

[pjholguin]

IMO All wiring point to point shall not have hidden splices, makes for easier troubleshooting. This should be spec. out...look at from the FSE point view...if there is problem with a signal it's best to know were all point of failures are, rather than having to tear apart the tool to find problem. Many man-hours saved this way...not to say the quality of the product produced. As for wire nuts, when I started the trade my journeyman would still solder his joints than wire nut. Technology has come a long way from than and there are quality splicing devices out...personal preference.

PJHolguin.

The 222 connectors make a "gas tight" seal... The majority of the situation where I would use the 222's would be in a junction box. I think my best bet for the pressure switches is to get tab'd terminals, and until then use the butt splices with the shrink tubing as extra protection. But back to my original quesiton, is it acceptable that they are "hidden" inside of the split loom as long as they are accessible because of the split loom.

We have some other equipment that uses a different directive, and uses molex connectors. Everywhere they make a connection they also break the conduit (loom or flex tubing) so that the molex connector can be seen. I think it looks terrible. I would rather not have to do that with the split loom if possible.

 

[GoldDigger]

Everywhere they make a connection they also break the conduit (loom or flex tubing) so that the molex connector can be seen. I think it looks terrible. I would rather not have to do that with the split loom if possible.

If it is truly split loom, and not just closed corrugated tube, you could simply put enough slack in the wire that the molex connectors rested on the outside of the split. Not nearly as bad looking IMHO, but tastes vary.