What's the difference? SO vs. SJO

Shawncfer

Active Member
between SOOW, SJOOW, SO, and SJ cable?

Ive googled, and KGBed it. And I havent found any answers. But I Know yall have to know!
 
Perhaps the wiki entry: Cable Types, S, SO, SOOW, SJ can illuminate.
 
Quickie answer is SO and SJ are the older and no longer manufactured versions, where as SOOW and SJOOW are the new current types, with improvements in the jacket design for resistance to chemicals, etc...

SOOW is heavy duty, with a thicker jacket, SJOOW is light duty with a thinner jacket.

For theatrical use, SOOW is the version allowed for on-stage use, below 12 ft. above deck level ? (12 or 20, cannot remember) and in lengths over 20ft. Thus typical multi-cables with male and female breakouts and fan outs can use SJOOW as long as the breakout is no longer then 20 ft.. I believe 2-fers are now SOOW as they need to be molded, as per recent UL listing requirements, thus no more 2-fers made with 12/3 SJOOW into a male 2p&G male plug.

SB
 
Quickie answer is SO and SJ are the older and no longer manufactured versions, where as SOOW and SJOOW are the new current types, with improvements in the jacket design for resistance to chemicals, etc...

SOOW is heavy duty, with a thicker jacket, SJOOW is light duty with a thinner jacket.

For theatrical use, SOOW is the version allowed for on-stage use, below 12 ft. above deck level ? (12 or 20, cannot remember) and in lengths over 20ft. Thus typical multi-cables with male and female breakouts and fan outs can use SJOOW as long as the breakout is no longer then 20 ft.. I believe 2-fers are now SOOW as they need to be molded, as per recent UL listing requirements, thus no more 2-fers made with 12/3 SJOOW into a male 2p&G male plug.

SB

I'm not sure about the 2-fer thing as we just got 72 brand spanking new 2-fers from LEX Products made out of SJTOW and terminated inside of the 2P&G male connector. I'll be really angry to find out that these brand new 2-fers which we just got delievered last Thrusday are not up to code...
 
Last edited:
SO cable is designed to be coiled and recoiled repeatedly
SJ is Tray Cable and not designed to be coiled and recoiled
 
... I believe 2-fers are now SOOW as they need to be molded, as per recent UL listing requirements, thus no more 2-fers made with 12/3 SJOOW into a male 2p&G male plug.
This is incorrect. Lex Products' Two-fer Junior, even when of the molded "Y"-style, use 12/3 SJTOW-A cable, and have a UL Listing.

See also this post, and particularly its attachment.
 
SO cable is designed to be coiled and recoiled repeatedly
SJ is Tray Cable and not designed to be coiled and recoiled

Sorry, not even close.

SO is an Extra Hard Usage cable, per NEC article 400.
SJ is a Junior Hard Service (Hard Usage) cable, per NEC article 400.

Both are Flexible Cables, neither is a Tray Cable.

Please see Wiki Entry called out by Derek for more infomation.
ST
 
This is incorrect. Lex Products' Two-fer Junior, even when of the molded "Y"-style, use 12/3 SJTOW-A cable, and have a UL Listing.

See also this post, and particularly its attachment.

Thanks Derek,

This was (to me) a recent change - I believe UL driven not NEC, about being molded and I couldn't get info. at the time I needed to do a proposal for replacement 2-fers, as to whether they allowed SJOOW for the molded portion, but it makes sense as they had allowed it for a non-molded.

SB
 
SOOW (or STOOW which you dont want to use as its plastic and will melt if it touches a light) is what is required for all cords in a theater. SJOOW may only be used for adapters and breakout tails. There is no exception for height off the deck, length if its a male to female cord, or anything else.
 
Just for the 413th time (no attitude here ;) ), v-style twofers using type SJ or its derivatives are allowed under NEC article 520.

ST

OK. What you are telling us Steve, is that 2-fers made with 2 pieces of 12/3 SJOOW cable, in a V design, using 2 pieces of cable into the male connector, is still allowed by the NEC. With a length limit of 36", if memory serves ?.

Is it UL listed if purchased new as a pre-assembled unit/device ?, which is a different issue and possibly why one of my suppliers would not sell me (and no longer carries pre-made) V style, but instead is only carrying pre-assembled as molded Y type ?. And is why they carry kits that assemble in a V design, which would be OK as they are not doing the assembly and thus don't care if the user assembles a device not UL listed ?.

As per MRB's comment "There is no exception for height off the deck, length if its a male to female cord, or anything else." Could someone more knowledgeable about the NEC answer/confirm these questions:

- Maximum length allowed for 12/3 SJOOW ?, which I thought was 20 ft in breakout only, not allowed as any single cable length usage ?.

- Maximum 2-fer length of 36 inches when using SJOOW, and/or is it 36" for ANY 2-fer or any construction ?.

- SJOOW only allowed a certain minimum height off stage floor ?, and if so, how does that affect breakouts below that height ?.

Going crazy in Brooklyn here.....

SB
 
OK. What you are telling us Steve, is that 2-fers made with 2 pieces of 12/3 SJOOW cable, in a V design, using 2 pieces of cable into the male connector, is still allowed by the NEC. With a length limit of 36", if memory serves ?.

Is it UL listed if purchased new as a pre-assembled unit/device ?, which is a different issue and possibly why one of my suppliers would not sell me (and no longer carries pre-made) V style, but instead is only carrying pre-assembled as molded Y type ?. And is why they carry kits that assemble in a V design, which would be OK as they are not doing the assembly and thus don't care if the user assembles a device not UL listed ?.

As per MRB's comment "There is no exception for height off the deck, length if its a male to female cord, or anything else." Could someone more knowledgeable about the NEC answer/confirm these questions:

- Maximum length allowed for 12/3 SJOOW ?, which I thought was 20 ft in breakout only, not allowed as any single cable length usage ?.

- Maximum 2-fer length of 36 inches when using SJOOW, and/or is it 36" for ANY 2-fer or any construction ?.

- SJOOW only allowed a certain minimum height off stage floor ?, and if so, how does that affect breakouts below that height ?.

Going crazy in Brooklyn here.....

SB

--6.0 m (20') max length for SJ (junior hard service or hard usage) and derivatives in breakout assemblies. Must be protected from physical damage by being supported over its entire length by a pipe, truss, tower, scaffold, or other substantial support structure. There is no minimum height off the ground specified. Must connect a single multi-pole connector containing two or more circuits and multiple 2-pole, 3-wire connectors. Must be protected by an overcurrent protective device of not over 20A. Section 520.68(A)(4)

--1.0 m (3.3') max length for SJ and derivatives in adapters and twofers. No length limit on twofers using SO or derivatives. Section 520.69(C)

All other applications require extra hard usage (SO and derivatives). Section 520.68(A)(1).

ST
 
Last edited:
36" max length for SJ and derivatives in adapters and twofers. No length limit on twofers using SO or derivatives. Section 520.69(C)

All other applications require extra hard usage (SO and derivatives). Section 520.68(A)(1).

ST

So.... Are sleeved twofers (fiberglass or plastic) NEC compliant? Have they ever been?

Also, a slightly related question. If one builds a M 60amp to 3 F 20amp adaptor, each 20amp leg needs to be protected. Is there a preferred off-the-shelf product that would be appropriate?

Given appropriate branch circuit protection, is there any way such a 'break-out' could be SJOOW?
 
So.... Are sleeved twofers (fiberglass or plastic) NEC compliant? Have they ever been?

Also, a slightly related question. If one builds a M 60amp to 3 F 20amp adaptor, each 20amp leg needs to be protected. Is there a preferred off-the-shelf product that would be appropriate?

Given appropriate branch circuit protection, is there any way such a 'break-out' could be SJOOW?

With regard to sleeved twofers, I would reckon no since three wires in a sleeve is not a cord type listed in article 400.

For 60 amp to three 20 amp, yes each 20 amp leg would need to be protected. You can obtain female 20 amp bates that have a fuse inside. This would provide protection and (i think) the short length of 12awg before the fuse would be ok under tap rules. This is not an ideal solution though as you have to take apart the female bates to replace the fuse. Most everyone these days is using a distro with 60 amp in and three 20 amp circuits out. These are available in both lunchbox and flat designs.

Yes your (properly fused) 60 to three 20 adapter could be constructed of SJOOW.
 
So.... Are sleeved twofers (fiberglass or plastic) NEC compliant? Have they ever been? ...
See this post, last point.

... Also, a slightly related question. If one builds a M 60amp to 3 F 20amp adaptor, each 20amp leg needs to be protected. Is there a preferred off-the-shelf product that would be appropriate?
Not exactly the same thing, but same concept: PowerFLEX™ Cable Assemblies: Stage Pin 100 Amp to 60 Amp Splitter | Lex Products. Note the conspicuous lack of mention of UL on the pdf.
mrb , I've used the female 2P&G connectors with a 20A cartidge fuse inside them, but can't find who made them and if they are still available. Got a link? One didn't need to take apart the connector to change the fuse, just open a little "door" on the side of the connector.
Sean , here is a sort-of off the shelf product. This post confirms it can be ordered with stagepin receptacles.
proxy.php

PowerHOUSE Portable Distribution Boxes: 60 Amp Motion Picture Brick | Lex Products

... Given appropriate branch circuit protection, is there any way such a 'break-out' could be SJOOW?
As long as each leg is limited to 3.3' (1m), no problem.
 
Last edited:
With regard to sleeved twofers, I would reckon no since three wires in a sleeve is not a cord type listed in article 400.

For 60 amp to three 20 amp, yes each 20 amp leg would need to be protected. You can obtain female 20 amp bates that have a fuse inside. This would provide protection and (i think) the short length of 12awg before the fuse would be ok under tap rules. This is not an ideal solution though as you have to take apart the female bates to replace the fuse. Most everyone these days is using a distro with 60 amp in and three 20 amp circuits out. These are available in both lunchbox and flat designs.

Yes your (properly fused) 60 to three 20 adapter could be constructed of SJOOW.

1. Sleeve twofers are non compliant because the only allowed use of this construction is for tails on high-temperature luminaires as covered in section 520.68(A)(3). Junior hard service (hard usage) cord was specifically allowed in section 520.69 to prevent the use of this type of non-compliant construction in twofers.

2. I don't think a 60A to 20A "adaptor" is actually an adapter as defined by 520.69, because it fails the "no reduction in current rating" rule of 520.69(A). It is actually a power distribution device covered by section 520.62. Therefore, any pendant cable involved in this device must be extra hard usage (SO), not hard usage (SJ).

In addition, I do not agree that any tap rule applies to a short length of flexible cord in the "adapter" you describe. . There are no tap rules that I know of for portable cord other than single-conductor feeders in sections 520.53(H)(3) and 520.53(H)(4). The overcurrent protective device must therefore be at the head end of the reduced-ampacity cord so that the ampacity of the cord and the rating of the overcurrent device are coordinated. This suggests a construction available from Lex, Union, and others, where the 20A overcurrent protective devices are contained in an enclosure, along with panel-mount connectors.

ST
 
Last edited:

Users who are viewing this thread

Back