Cam Turn Arounds

SteveB

Well-Known Member
The gender of the neutral and ground Cam's has 2 camps:

1) Keep all the Cam's the same gender as that's the way it is with every other connector.

2) Reverse neutral and ground so some numbnut doesn't plug a cable coded as one of the Hot legs (Black, Red, Blue) cable Cam's into a neutral or ground feed off the company switch. Especially with the fly-by-night companies whose cam-loks have blue electrical tape "mostly" covering the green cam-lok connector, making you wonder what the hell it's supposed to be - hot or ground. This is an issue with connections that can bye-pass the intent of the NEC requirement that Ground make first/break last connection.

I'm all for reversed neutral and ground and keep a set of turn-arounds for my space.
 

derekleffew

Resident Curmudgeon
Senior Team
Premium Member
3) Certain audio companies reverse only the ground or neutral, but not both. Never quite understood the logic, if any, behind that practice.
 

firewater88

Active Member
The gender of the neutral and ground Cam's has 2 camps:



2) Reverse neutral and ground so some numbnut doesn't plug a cable coded as one of the Hot legs (Black, Red, Blue) cable Cam's into a neutral or ground feed off the company switch. Especially with the fly-by-night companies whose cam-loks have blue electrical tape "mostly" covering the green cam-lok connector, making you wonder what the hell it's supposed to be - hot or ground. This is an issue with connections that can bye-pass the intent of the NEC requirement that Ground make first/break last connection.

I'm all for reversed neutral and ground and keep a set of turn-arounds for my space.


the audio company that I usually have in my space has reversed ground and neutral. I used to just leave the turnarounds on the cam tails. I recently experienced issues with my cam sets into the panel, so i made up some bare ends at the panel and cam ends at the other and did it so they stay with the 200A service for that audio co so i don't need turnarounds.

I have a double neutral setup from ETC- have yet to see any gear come through with double neutral.

I also have a bunch of "T" connectors in my box of tricks. Never used them, but if I did, then I might need my plethora of turnarounds to make a connection work. Highly unlikely I would need them as I have (2) 400A ETC Company Switches, (1) 200A ETC Company Switch and (1) 200A service on the side.
 

Pie4Weebl

Well-Known Member
Fight Leukemia
Total frivolity provided one is using (non-banded) single conductor feeder and EVERY rack has pass-thru's. If not, it's the house's problem.:twisted:

That is really dangerous. If someone were to disconnected the feeder to the next rack while power was hot (something I don't do, isn't safe, so on) they would pull the neutral and ground to the live rack as opposed to the next rack and have a very bad situation.
 

bishopthomas

Well-Known Member
That is really dangerous. If someone were to disconnected the feeder to the next rack while power was hot (something I don't do, isn't safe, so on) they would pull the neutral and ground to the live rack as opposed to the next rack and have a very bad situation.

Pass through Cams are a very standard feature on distros. I'm not really following what you're concerned about. Are you saying that it's dangerous if someone pulls the power from the second rack (the one getting its source from the pass through)? I'm not sure what's dangerous about that, as long as the pass through Cams have the spring-loaded covers on them. Although, I'm not sure why anyone would go pulling feeder while the show is still going (amp rack with pass through still live).
 

ship

Senior Team Emeritus
Premium Member
I'm also of the camp that reverses the neutral and ground. Obviously in the past there must have been an instance in not properly idiot-proofing the system that someone has had a problem of misconnection, otherwise why would someone do so?

The turn-arounds are only for use in connection where others don't comply to such a safety thing in my opinion. - This even if only properly trained and qualified service personel are to be doing such connections.

Now the loomed -wire cable (have not seen six wire in a few years) and it's derating... assuming we are loomed but never go above 80% rating of the cable... that is something I think about in compliance. Also starting to switch to the Bates/Marico hard plastic female connectors over the preferred ECT Leviton line. Tired of the females wearing out where it hits the brass. TBA how well the hard plastic holds up but given labor and materials needed to swap out the rubber based receptacles, worth a try.

Than there was the time the old timer of our shop had the idea for me to start using steel 16ga tie wire for the strain relief inside plugs... Rust and corrosion on all that series of plugs later.

Tip on idiotproofing CanLoc's, McMaster sells a ratchet torque wrench adaptor that you can pre-set and lock to a specific torque seting. A bit tricky and needs a real torque wrench to set that setting but really useful in insuring the proper torque. Side point about this, Marinco sells a male pin resrufacing tool. Bought it but yet to need it other than a bad lot number from Leviton at one point where they just didn't match well.
 

willbb123

Active Member
Our ground and neutral are reversed.
We had this group come in a little over a year ago, I don't remember the show, but they were just starting out on the road. I go to connect the cams, and notice their banded cables weren't reversed. We don't have turnarounds, and neither did they. Their lighting guy started to panic, and called back to his shop to see what he could do. After some confusion on the phone, I hear, "No... You don't understand, the problem is that I have two hot females, and I can't do anything with them."
 

bishopthomas

Well-Known Member
Our ground and neutral are reversed.
We had this group come in a little over a year ago, I don't remember the show, but they were just starting out on the road. I go to connect the cams, and notice their banded cables weren't reversed. We don't have turnarounds, and neither did they. Their lighting guy started to panic, and called back to his shop to see what he could do. After some confusion on the phone, I hear, "No... You don't understand, the problem is that I have two hot females, and I can't do anything with them."

That's funny! Although, if you're going to turn around the cams then it's your responsibility to provide turn around adapters. At the same time, the touring company should have had a set with them.
 

STEVETERRY

Well-Known Member
I'm also of the camp that reverses the neutral and ground. Obviously in the past there must have been an instance in not properly idiot-proofing the system that someone has had a problem of misconnection, otherwise why would someone do so?

The turn-arounds are only for use in connection where others don't comply to such a safety thing in my opinion. - This even if only properly trained and qualified service personel are to be doing such connections.

Now the loomed -wire cable (have not seen six wire in a few years) and it's derating... assuming we are loomed but never go above 80% rating of the cable... that is something I think about in compliance. Also starting to switch to the Bates/Marico hard plastic female connectors over the preferred ECT Leviton line. Tired of the females wearing out where it hits the brass. TBA how well the hard plastic holds up but given labor and materials needed to swap out the rubber based receptacles, worth a try.

Than there was the time the old timer of our shop had the idea for me to start using steel 16ga tie wire for the strain relief inside plugs... Rust and corrosion on all that series of plugs later.

Tip on idiotproofing CanLoc's, McMaster sells a ratchet torque wrench adaptor that you can pre-set and lock to a specific torque seting. A bit tricky and needs a real torque wrench to set that setting but really useful in insuring the proper torque. Side point about this, Marinco sells a male pin resrufacing tool. Bought it but yet to need it other than a bad lot number from Leviton at one point where they just didn't match well.

Some history:

1. Cam-Lok E1016 connectors were first used in an entertainment application on Colortran 6 x 6kW portable dimmer packs, circa 1977. In order to attempt UL Listing, they needed non-intermateablility of hot, neutral and ground. This was at least 7 years prior to NEC recognition of single conductor feeders and single-pole separable connectors, with their associated connection-order rules. Without these NEC rules, UL made up some of their own: no intermateability of hot, neutral, ground. (Note that even today, the NEC makes no statement about non-intermateability of these specialized connectors).

2. Colortran used Empire Products E1016 males on the hots, an E1016 female on the neutral, and a female Palmgren Screw-Lok on the ground. The Palmgren Screw-Lok was a hideously expensive, long lead-time connector that used the same female neoprene housing as an E1016, but was not mateable with E1016. Another great feature: its cable boots only came in a vulcanized version, not the "Lektra-Link" style that is now standard on E1016. That meant:

--A vulcanizing press
--Vulcanizing tape
--Gooey vulcanizing lube
--At least 10 minutes curing time per connector
--No field installation or removal, unless you had a vulcanizing press in your workbox

proxy.php


Palmgren Screw-Lok connnectors
www.integro-usa.com

3. Production Arts owned a bunch of those Colortran packs, and after extreme frustration with the Palmgren Screw-Lok's, we changed them out for female E1016's. Our logic: better to guarantee no intermate of hots with neutral and ground. That arrangement became our standard on touring gear, and I guess our logic caught on with some other rental companies-- but there were notable holdouts such as Vanco.

ST
 
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jstroming

Active Member
Speaking from experience (I do about 70 hotel shows a year between two of the tours I oversee) I would guess that about 60% of the venues my shows travel to have Bare-End Tie-Ins. For reference we have contracts with Hyatt's & Westin's and only go to ballrooms & halls over 12,000sf. The other 40% are Cam's, and of them the majority (75%) DO reverse their Neutrals & Grounds on 200A & 400A services (which is what we book). We have banded & unbanded 4/0 (depending on the show) so Cam-turns are a neccessity. Add in the "forgetful" stagehand, "unknowing" stagehand, and "pissed off" stagehand, and they keep my road crew from committing suicide!

On another topic...I like to see just how badly hotel electricians tie in tails...Let me tell you I have seen some SCARY stuff....E-taped & zip-tied bus bar's seem to be a favorite of hotel electricians. I once even saw an electrician who couldn't get the 4/0 into his bar, so instead of cutting back some of the copper (which come on we all do in a bind) He instead LEFT THE HEX KEY IN THE TERMINAL SCREW, and I kid you not split the copper around the metal of the hex key and "twisted" off the end on top of it. I took a picture and printed it, then gave it to the crew-chief after us..."Good Luck!" lol.
 

erosing

The Royal Renaissance Man
split the copper around the metal of the hex key and "twisted" off the end on top of it. I took a picture and printed it, then gave it to the crew-chief after us..."Good Luck!" lol.

Well, that's a new one!
 

derekleffew

Resident Curmudgeon
Senior Team
Premium Member
jstroming, in the nineteen years I've been in Las Vegas, I can count on one hand the number of times I've used or seen used bare-end tails. That being said, every rock tour carries them. First thing out of the feeder box, and last thing back in the box at the end of the night. If turnarounds are needed, either the house electrician or the electrical contractor provides them. When paying a hotel $1000/day (or more) to provide a 400A service, it's not too much to ask, IMHO. I also carry my own, but rarely use them.

Thanks for the history lesson, Mr. Terry. FWIW, I don't recall ever turning around Tweco's.:angryoldman:
I'm reminded of 7-10 years ago when a large lighting production company that always reversed bought another large production company that never reversed. To this day, they are still sorting out that one.

I find it interesting that generator and portable power companies never reverse, and they deal with single-pole connectors more than any of us ever will. They carry turnarounds (often black only, with or without face tape) just for our industry.
 
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jstroming

Active Member
We havent hit Vegas in a few years, maybe that's why. Also I think the frequency of (large) events in Vegas may make having cams more of a priority than venues that rarely have shows tie into 200A boxes. Now that I think about it, my hometown (NYC) has more venues than not with cams, but we still have our fair share. Especially older venues.
 

wolf825

Senior Team Emeritus
Premium Member
I once even saw an electrician who couldn't get the 4/0 into his bar, so instead of cutting back some of the copper (which come on we all do in a bind) He instead LEFT THE HEX KEY IN THE TERMINAL SCREW, and I kid you not split the copper around the metal of the hex key and "twisted" off the end on top of it. I took a picture and printed it, then gave it to the crew-chief after us..."Good Luck!" lol.

Thats definitely up there along with the hotel electrician I got once who didn't even take the orange etape off the exposed tail wires which were wrapped for transport--he just lugged everything in as it was--might as well not have bothered to strip the tails new before leaving the shop...and then there was the hotel that took a spare lug and made some bastardized in-line "thing" wrapped in half a roll of etape that connected/jumped one of my bare wire tails to a hanging regular #2 bare wire they 'couldn't get out of the panel' that had been there for a long while it looked like...

I'm of the ground/neutral reversal camp....I have them turned around in my venue company switches...and keep T's and turn-arounds in my venue as a convenience for folks who may come in and have 'forgotten' theirs.....but over the years I have worked for shows and shops all over that either reverse or not reverse. Back when I was introduced to these on my first show too too long ago, I got a lecture from my head electrician mentor at the time on why folks do or do not reverse (they were NOT reverse folks).. It went something like this:

"The G/N Reverse <cuss word> believe that it is the "safer" way to go for those times when you have folks who are new or who you have never worked with--you know that they can simply match colors and even if they can't--things will still be safe with hots to hots and G/N to a G/N cause only one way to hook em up....to them its simply a safer way to go and they think any colorblind monkey is qualified to handle power and feeder and can make the connections and not kill anyone which is just BS in my book..so those folks hand feeder cable to anyone and feel they are OK... Now WE don't reverse cause its even simpler a reason--us no-reverse folks believe that no one who does not know what they are doing and who is not familiar with power should have any business running or connecting high voltage lines or even TOUCHING our cables and god help them if they do and I catch them with our cables in their hands..so its simple--you know what you are doing when it comes to power or you don't and you don't do it.."..


While a bit on the rough side--Makes sense to some point...and yet I am on the side of reversals..cause I have seen a lot of folks who don't know still try and do it.. In our business safety is all the difference between professionals and ignorant yahoos out 'playing' at other peoples risk..IMO... Although later on in my career I have seen some stupid crap that makes me wonder if even reversal is safest.. I was in one hotel up north on a show where the hotel electrician connected the cams together (reversed set of tails) to the banded and was ready to throw the switch--and except for the green and white this guy did NOT follow color code to the hots. When I asked about this as I came to meter power prior to energizing the system--and found my blue with red, black with blue and red with black--I asked him why he didn't follow color code on the legs--his response was a blank stare and then simply "Que??...make ON now?". <smack>




-w
 
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Footer

Senior Team
Senior Team
Premium Member
In my space I have 4 200 amp disconnects that are all bare end. The college I attended was all bare end. The arena I worked at in college was also all bare end. The theatre that my summerstock company occupies is also all bare end.

I think it really just comes down to how often people tie in and how old of a venue you have. Nearly every new venue I have seen in the last few years has had one of the LEX company switches with all its LED gizmos and such. However, even this very expensive switch still has terminal connections!
 

bishopthomas

Well-Known Member
and then there was the hotel that took a spare lug and made some bastardized in-line "thing" wrapped in half a roll of etape that connected/jumped one of my bare wire tails to a hanging regular #2 bare wire they 'couldn't get out of the panel' that had been there for a long while it looked like...

There's a certain township in NJ that uses this method. They "tie us in" by plugging us in to their bare wire with lug thing and taping the hell out of it. I always want to bury it, as they just kind of tuck it under the mobile (outdoor) stage.
 

SteveB

Well-Known Member
Steve Terry and Dereks recollections about the assorted shop method(s) brought to mind that when I first started seeing G/N reversed it seemed to be an "East Coast" vs. "West Coast" thing, in that the NYC area "stage lighting" shops had G/N reversed, while the film folks (read - West Coast) and any shop outside of the NYC area used all Cam's same.

Now all I see is G/N reversed, especially on PD's coming stock out of Lex or Motion Labs and of course the big NYC area shops - PRG, 4 Wall and Scharff-Weisberg.
 

Pie4Weebl

Well-Known Member
Fight Leukemia
Pass through Cams are a very standard feature on distros. I'm not really following what you're concerned about. Are you saying that it's dangerous if someone pulls the power from the second rack (the one getting its source from the pass through)? I'm not sure what's dangerous about that, as long as the pass through Cams have the spring-loaded covers on them. Although, I'm not sure why anyone would go pulling feeder while the show is still going (amp rack with pass through still live).

Perhaps there is some mis communication, what I thought the poster was suggesting that was if the rack has cam pass throughs and the g/n are reversed you just flip which row you plug the feeder into. So the bottom row on the rack is the 3 phases in on the rack and g/n out to the next, then on the top its it 3/phases out to the next rack and the g/n in to the first rack.

So the issue that may arise is say its a house 120K in the first rack and then the touring group daisy chains from that, if they g/n are plugged into the opposite row and they pull their feeder with out the main racks powered down they could inadvertently pull the pull the g/n that feeds the whole thing as opposed to just the line running to the next rack, if they just unplugged everything in the top row.
 

STEVETERRY

Well-Known Member
Perhaps there is some mis communication, what I thought the poster was suggesting that was if the rack has cam pass throughs and the g/n are reversed you just flip which row you plug the feeder into. So the bottom row on the rack is the 3 phases in on the rack and g/n out to the next, then on the top its it 3/phases out to the next rack and the g/n in to the first rack.

So the issue that may arise is say its a house 120K in the first rack and then the touring group daisy chains from that, if they g/n are plugged into the opposite row and they pull their feeder with out the main racks powered down they could inadvertently pull the pull the g/n that feeds the whole thing as opposed to just the line running to the next rack, if they just unplugged everything in the top row.

I think we need to remember that single-pole connectors and single-conductor feeder systems are only for use by Qualified Personnel, per the NEC. Cam connectors can be thought of as "tool-less lugs", but the responsibility for the design and correct installation of the feeder system rests with the qualified person installing it, just as if it were permanent wire in conduit. Arrangement of connector rows and/or neutral ground sex in a feed-through rack would not be something that would be a problem for a Qualified Person, since they would clearly identify and mark each feeder set at both ends as to its function.

ST
 

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