Sensor vs ET Intelligent Raceway

thommyboy

Active Member
I am working with a group specing out for a new space. We are looking at a mostly ETC rig in terms of control (Eos main ION studio) and fixtures(S4 ERS, Zoom, PARnel).
What I would like to know is given the option would you rather have an Entertainment Technology IGBT Intelligent Raceway with the 220v drops and Data runs OR Sensor Racks and have to run additional power and data runs for the intelligent fixtures (VL 3500 wash and spot)
 
If you can afford the sensor install, do that. I am a big fan of the smart bar technology if you need 12 to 24 dimmers in a multi purpose space. It saves on wiring and space. I would never attempt to put that system into a large facility just due to scalability concerns. With one of those systems you have a lot more failure points throughout the system, not to mention what you have to go through to reset a breaker. You will be much happier with an installed rack, if you can afford it. However, if the installed rack vs more dimmer question comes up, take the more dimmers.

I have not worked with one of these systems that flys before, but I do have a feeling they weigh more then a traditional raceway. Be sure to take the weight into consideration. I have been to too many places that require an electric to be married after putting 15 fixture on it because the raceway weighs to much.

Also, (and ETC will do it) you can get a data drop on every electric as well as a twistlock connection on every electric. These twist lock connection should be wired to a relay module, not a dimmer module, and you will have instant mover power and on every electric. I have this in one of my spaces and its fantastic.
 
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I once did a price sheet for sensor racks and the bars. The bars were going to end up costing much more and the threat of heat was an issue (top of this place would get to be 100+) The big cost came into running all off the power up to the catwalk and all over. Also the problem of having one go out and then you losing a bank rather than just one channel. Also the loading on a per channel basis. I want to say they are only 1200W max so you cannot even plug 2 750's into one dimmer which really made it look bad. The racks turned out to be a much better choice (there is a reason why all of these big install companies are installing racks over bars). Also you have to factor in you can only have 32 bars per dmx output, so the cost of all the extra data runs along with splitters really kicked the price up. What i do is i install a sensor rack, and then next to the rack i install a panel that that provides circuits to the moving lights. I then install the plugs where appropriate throughout the space. Running power for 220 costs the same as running power for 110V except for the cost of plugs which gets expensive quick. There is no since in buying 220V relay modules for the sensor rack and then losing all of your potential dimmer space. It is much more cost effective to just run another panel (if your transformer is big enough, it probably will be, just run the panel off of the same transformer). What also works really well for budget constraints but future upgrades is to run some extra pieces of conduit from the mover power to the catwalk and off stage somewhere incase you decide to add more later on. You never know if you decide to even add some 3 ph in for chain motors b/c your lighing positions from the cat are worthless.

Also its totally worth getting a data drop onto each electric including at least one data drop to the catwalk. Put all of you data drops on a seperate universe than your dimmers.

Also have you actually fully checked out the ION or just word of mouth? I get along better with a strand 520 than i do with an ION but thats my personal opinion. We have been spec-ing the road hog for all new installs, its the same price with a lot more functionality.
 
Pro's and Cons to both

ET IGBT Pro's

- The big claim is less cable needed saving on wiring costs. A circuit breaker panel is needed somewhere for the 3 pole 20 amp breakers going out to the bars, as 3 circuits/dimmers can share a neutral, VS. having to run separate neutrals PER CIRCUIT on a central DPC system.

- Ea. outlet has a local On/Off switch for testing, focus, etc,, easily over-ridden from DMX control.

- You automatically get DMX at the position, as the bar/box needs control. Not sure how robust the ET network and DMX/Data distro is, though the website lists Ethernet at the raceway, with Pathport available.

- IGBT's are very reliable, and - in theory - you don't run into issues having to reset breakers due to shorts, etc...

- They come in 1.2kw circuits, which is very appealing, especially given the ETC survey that indicated few loads were above 750, typically. I believe a single 2.4kw IGBT can power dual circuits at 1.2kw, which can be very useful if you suddenly need a 2kw fresnel. Having 1.2kw's, can greatly reduce the cost of wiring. Instead of running 12 - #10's for 6 x 20 amp branch circuits, you run 4 - #10's for either 3x2.4, OR 6x1.2, seems very cost effective.

ET IGBT Con's:

- Few in use (as compared to Sensor), thus parts ?, support ?,

- Network/Data distro ?, seemed weak when I looked at it years ago, but back then it was all DMX, now it's Ethernet, which is off-the-shelf stuff, and they're doing Pathway now, so possibly improved.

- Heat ?. Big issue, as the heat load for the theater is now at the raceway, not in a controlled HVAC environment, where dimmer racks want to be. Note that the ET devices are very, very sensitive to heat and care must be taken to guarantee correct air flow around the raceway/boxes, as there are no fans to get air moving.

- Weight ?. This was a HUGE issue for us, as the ET Raceway is a lot heavier then a standard raceway, and if it's not on a winch, I wouldn't do it.

- IGBT's are not a huge improvement to standard SSR's, thus no real advantage, possibly less harmonics ?. Not sure about that.

- No ability to convert a circuit to dedicated clean power. IGBT's do not power ML's any nicer then an SSR. Thus still a need for dedicated power, though the ET website makes mention of ability to be fed 120 and 208 constant power for ML power. Not sure exactly what they are doing.


ETC Sensor/Central rack thoughts:.

- Rock solid, parts readily available and will be for ever. ETC support

- Ability to convert a pair of circuits to relay/constant, thus possibly less requirement for a lot of dedicated power everywhere.

- The ETC "System" - I.E., console, dimmers, network and nodes, RRFU's, as well as raceways and distro, is very robust.

- Everybody uses ETC thus everyone understands it.

ETC Cons:

- Not many, just the need for a lot of separate dedicated power outlets, though the system we are currently designing will spec. as SmartSwitch, which can do 208. I'm not spec'ing 208 though, as very few ML's NEED 208, as all are self sensing and can run off 120, just more circuits needed for a lot of fixtures. Does installing 208 help you with anything else ?.

My initial $.02

Steve B.
 
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I am working with a group specing out for a new space. We are looking at a mostly ETC rig in terms of control (Eos main ION studio) and fixtures(S4 ERS, Zoom, PARnel).
What I would like to know is given the option would you rather have an Entertainment Technology IGBT Intelligent Raceway with the 220v drops and Data runs OR Sensor Racks and have to run additional power and data runs for the intelligent fixtures (VL 3500 wash and spot)

I have some thoughts on this, and my company Production Arts was probably the first large adopter of ETI IPS dimming in the 90's. Now I work for ETC.

So, with everyone's permission, I will lurk for a while longer before weighing in, so we don't run the risk of turning this thread into a commercial spat until the end.

So we can consider the answer carefully, can you tell us what size of systems you are considering? Please tell us the total number of dimmers and capacity for both the rack and distributed choices.

ST
 
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Thank you for your restraint, STEVETERRY.;)

thommyboy, just curious why you're limiting the discussion to an installed rack vs. an IGBT raceway? One would think there would be some savings gained by sourcing everything from one manufacturer. Have you considered the SmartBar and/or SmartModule?

Many of us have seen the Rack vs. "dimmer at the fixture" debate before. In the 1980s some Rock&Roll lighting companies tried to convince us "dimmers in the truss" was the future. I don't know of a single touring company doing that today. Of course, I had the same thoughts about powered speakers.:(
edit: Research shows that the concept of "dimmer at the fixture" was proposed in A Digital Lighting System for the Theatre, Master Thesis of Fine Arts Yale School of Drama pp. 1-48, May 1974 by Dirk Epperson. Once an assistant to LD F. Mitchell Dana, Mr. Epperson today is VP and Co-Founder of http://www.kabira.com/, a software solutions company.

...I'm not spec'ing 208 though, as very few ML's NEED 208, as all are self sensing and can run off 120, just more circuits needed for a lot of fixtures. Does installing 208 help you with anything else ?...
thommyboy specifically mentioned "VL 3500 wash and spot," which require 200-240 VAC, 50/60 Hz.
 
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I am looking for 288 dimmers. The reason I was looking more to the ET intelligent raceways was the scalability. It looked like they could be used for a larger install than the smartbar/smart module.

I was thinking the raceway also for the ability to place pig tails, DMX and 208 in a single package...though I guess that does increase the chances for a single issue turning into multiple issues.
 
I have an install of almost 400 IGBT dimmers on 8 electrics, and have roughly the same size install of sensor racks in another space, and have had both for at least 5 years (the Sensor one longer). I think both are great products, but based on heavy usage, I would recommend the Sensor racks. Definately pay to get the data drops and power for moving lights though. It is a great thing to have.

~Dave
 
FYI, heat and weight really are not an issue for us with the ET System. Yes it is more weight, but we move them on standard single purchase counterwirght systems with on real issues. The heat is not an issue at all.

~Dave
 
As long as space and cooling is available for the racks, that would be the way to go. For that many dimmers, IGBT would only make sense if you were severely space constrained.
 
There are many 208V movers out on the market that only work on 208-240V. All of these types of movers use magnetic power supplies. Also, many companies run them at 208V through their distro so you drop your amperage load. When it comes to big moving light rigs anything helps. Magnetic ballests are cheaper and less likely to fail over electronic ballasts, though they are less effecient. Also i do not like running anything over 700 watts on a 120V circuit.
 
I have an install of almost 400 IGBT dimmers on 8 electrics, and have roughly the same size install of sensor racks in another space, and have had both for at least 5 years (the Sensor one longer). I think both are great products, but based on heavy usage, I would recommend the Sensor racks. Definately pay to get the data drops and power for moving lights though. It is a great thing to have.

~Dave

Forget the engineering theories and advertising hyperbole---this is real-world and unique experience worth listening to!

And thus, I retire to the sidelines!

ST
 
...I was thinking the raceway also for the ability to place pig tails, DMX and 208 in a single package...though I guess that does increase the chances for a single issue turning into multiple issues.
I'm sure ANY (well, almost any) theatrical dimmer and raceway manufacturer can incorporate dimmed 120V, switched 208V, DMX, convenience 120V, and Ethernet outlets in a single raceway. All those panelboards and data-distribution devices have to live somewhere--why not conveniently located in a "dimmer" room?
 
I'm sure ANY (well, almost any) theatrical dimmer and raceway manufacturer can incorporate dimmed 120V, switched 208V, DMX, convenience 120V, and Ethernet outlets in a single raceway. All those panelboards and data-distribution devices have to live somewhere--why not conveniently located in a "dimmer" room?

This follows ST's long-held theory of dimmer economics:

"A dimmer rack is a distribution panel with some free dimmers".

And it's just that, when you factor in the cost of getting from 100,000A of available fault current (on a typical 800A feeder) down to 10,000A of Short Circuit Current Rating on a 20A branch circuit. You can't do it with a single breaker panel, you need many of them--with the associated labor to wire them up.

Do the math with multiple breaker panels and then with modern, high-SCCR dimmer racks: the dimmers are free.

You don't get that with distributed dimmers.

ST
 
So much for staying on the sidelines.:lol:

Slightly different topic. I'm wondering about the future of Entertainment Technology, Inc. ET has had the Bak Pak Individual Dimmer for some time.
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Just recently, Strand Lighting has introduced the Light Pack Dimmer.
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One cannot help but notice the similarities, and the situation becomes curiouser if one is aware that ET holds a patent on IGBT dimming.

Of course, Strand and ET are sister companies, under the Genlyte/Philips umbrella. I'm also unclear about the status of ET's Marquee™ console, if anyone would like to enlighten me on that. Strand-ET-Vari*lite-CK-Lightolier-Stonco is certainly a mouthful. Even couriouser is who's missing from the www.genlytecontrols.com page.
 
Wow There have been a lot of great posts in this thread! Some really great info and opinions. A lot of the variables have been discussed very well. As you can get almost any dimmer package in almost any arrangement; you can get as many data drops and power feeds as you are willing to pay for or can afford, or that your facility will support, I feel a lot of the choice comes down to whether you're a Mac or PC kind of person. I have a deep seated love for IBGT dimmers, I don't like Macs, But I feel IBGTs are sort of the Mac of dimmers. They're a bit more expensive initially, but you simply can't beat them for safety. They have more compatibility across the board like PCs do but they have a much better "Plug and Play" capability. Need to run a motor? Balasted light source? Incandescent? Just plug it inand turn it on. Try that with an SCR.
 
Some random thoughts

I'm sorta of facing a similar decision about distributed or collected (dimmer rack) for a new complex going in, in the next few years.

In my mind, I don't see enough advantages to recommend IGBT over SCR, the IGBT does not allow "Non-Dim" power to a ML, so the advantage of "Plug and Play" is not (in my mind) a reality and a Sensor handles a mirror ball motor or gobo rotator just fine, and can at least have dual circuits swapped to relay, which you cannot do with IGBT raceways. IGBT has theoretical advantages in terms of dead short protection, but from a user that has tripped breakers maybe 6 times, on a 300 dimmer Sensor system in 4 years, I don't see any big advantage.

One advantage to IGBT I see, is in a scenario we are facing with 3 FOH catwalks that probably would work well with 32 x 1.2kw dimmers (96 total) across 40 feet or so, all fixtures on individual dimmers @ 1.2kw. The cost savings in wiring "may" be actual,. though ST brings up a very valid point that the labor to install circuit panels for 32x20 amp, 3 pole breakers, as power distro to IGBT raceways, might eat up the savings in copper.

And you still need dedicated power for the ML's of the future.

As other have pointed out, there are many ML's wanting 208v, though I question as to the application of the larger and brighter ML's that need 208, being needed in smaller spaces. You still need "some" 208 around, so best plan for it, but I have a question - are the fixtures needing 208, using 208 only beceause they are brighter ?, or is the feature set of the larger fixtures what people are after ?.

The ETC SmartSwitch system, "seems" like a good way to go, but as I discovered, they do not have internal circuit breakers, so you are back to the labor issue of installing and wiring up separate breaker panels alongside the SmartSwitch panel(s), so at what point is it cheaper to simply make the dedicated power circuits needing DMX control into a Sensor rack with relays. Sensor is very, very easy to wire up. (Edit: - SmartSwitch does allow for 2 pole circuits, which Sensor does not).

The IGBT systems, as well as standard raceways that offer built in Ethernet or DMX, have to pay close attention to providing for separation within the enclosure of the lo-vo section with the 120v. Combing Lo and Hi voltage in raceways, while seemingly desirable, forces you to think about the robustness of the data cable running/bundled alongside the 120v multi. This is less an issue when the raceway isn't flying - catwalks, etc... where you can specify off-the-shelf Cat5 receptacle panels somewhere convenient to the devices needing data. You still need to do some thinking about data to moving positions that use Soca for dimmed distro, or that are getting dedicated power. Many questions in my mind as to how to do this well.

I'm currently toying with the idea of not overloading on racked dimmers, especially at positions that will see occasional use, but simply putting in a lot of dedicated power off Sensor relays, as well as lots of local data ports, then buying a whole bunch of BakPaks or Leprecon 4 way dimmer packs. Then the circuits can be ML power, OR power to a dimmer pack for conventionals. An example is a series of 19 balcony rail positions that can handle 3-4 conventionals, OR maybe 1-2 ML's, ea. Rather then put in 4 circuits @ 2.4kw dimmed, I'll install 2 @ 2.4kw as relay. Thus I have ML power for easily 4 fixtures @ up to 700 watt lamp types, OR a Leprecon 4 pack that can run on 2 circuits and provide for 4 x 900w dimmed circuits. Do I need 208v ML fixtures here, probably not.

In any event, I wish ETC still made the old LMI quad 1.2kw dimming rack that had (if memory serves) 192x1.2 dimmers in a rack. Put that in a Sensor and I'd spec. it in a minute. Trouble I see is a re-design would be required to fit 192 lugs for branch circuits, not to mention more space needed for the chokes. Or maybe a cheap Sinewave @ 1.2kw ?.

Steve B.
 
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Wow There have been a lot of great posts in this thread! Some really great info and opinions. A lot of the variables have been discussed very well. As you can get almost any dimmer package in almost any arrangement; you can get as many data drops and power feeds as you are willing to pay for or can afford, or that your facility will support, I feel a lot of the choice comes down to whether you're a Mac or PC kind of person. I have a deep seated love for IBGT dimmers, I don't like Macs, But I feel IBGTs are sort of the Mac of dimmers. They're a bit more expensive initially, but you simply can't beat them for safety. They have more compatibility across the board like PCs do but they have a much better "Plug and Play" capability. Need to run a motor? Balasted light source? Incandescent? Just plug it inand turn it on. Try that with an SCR.

Sorry, but I don't agree with your view about an IGBT dimmer dealing well with many different load types. History proves differently.

The ET IGBT dimmer operates in either forward or reverse phase control mode. A load with any inductive component cannot be used with reverse phase control. Either you manually force the dimmer into forward phase control mode for such a load, or you rely on the dimmer's internal sensing of the inductive load to automatically switch to forward phase control. This does not always work perfectly, in my experience. The result can be a failure.

Now a well designed sine wave dimmer that uses IGBT's as the power devices is a different story. That type of dimmer has wide tolerance of a lot of "odd loads".

In fact, SCR dimmers are quite tolerant of many types of resistive, inductive, and capacitive loads.

As your your "safety" comment--please elaborate, since right now I see no basis in fact or history behind that statement.

ST
 

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