Control/Dimming Removing dimmers and replacing with a breaker box, thoughts?

mtodd2qq

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Sorry long winded background info. We have a small auditorium built in 1907. at one point some one installed a 12 dimmer Dove pack into the space. We have one DMX 5 pin line from the board from the back of the house ran along the wall to the dimmer for control. From the dimmer we have 12 hardwired lines to our only lighting position, a beam running across the front of house area. House lights are a light switch, work lights are a light switch. Nothing but those 12 positions are on the dimmer.
Someone before me hung 4 LED Pars along side the traditional instruments, ran a cord from the back wall for power and is controlling them with a show baby.

The dimmer pack is dying as they do. Our facilities head has done some research and asked me a simple question

Instead of replacing the dimmer pack, why not put in a breaker box, and replace all the incandescent instruments with LEDs that dont need a dimmer, and then control them with that little orange box up there.

Anyone have any experience with this or advise they want to offer if they have? Its never going to be a true theatrical space, they wont be doing a renovation anytime soon, they wont be adding additional lighting positions. This seems like a simple solution and a no brainer, which is why it has me worried I am missing something. thanks
 
What specifically are the traditional fixtures you have now? Type, make, model, wattage?
Dove is pretty reasonable at fixing their stuff; it might be worth a phone call or email. The lure of LED is great, but it will cost some money to get acceptable smooth dimming performance.
What acceptable performance is, is relative. Also, how many channels does your control console have? Most LED fixtures require at least 3 channels each (RGB), some more and some (white light only) less. Maybe provide a bit more specific information?
 
Provided everything attached to it is up to code as permanent wiring, then you should be ok in doing that with one specific caveat:
Do not use circuit breakers as switches! There are some that are rated for that, but most are not. If these need to be switched circuits, the switches should be separate from the breaker box. Needless to say, all work should be done by qualified, licensed, and insured personal.
 
This might be a good application for ETC's economical Foundry relays so your console's DMX can switch the power on/off to your LED fixtures.
I agree but needs breakers.

If you go to LED, you might only need one circuit. Rule of thumb is 10 fixtures per circuit. Lots of exceptions but so maybe 2 circuits to replace 12 dimmed.

But not stated explicitly above - you need to depower LED fixtures when not in use. So relays usually.

But sufficient numbers of fixtures and most rudimentary infrastructure for a modicum of reliability and medium quality is thousands of dollars. Can you do that?

Thanks Ron for editorial help!
 
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The posts so far also allow confusion of white light LEDs with color changing fixtures.
You're right. I have assumed LED rgb+ theatrical lighting fixtures with integral DMX drivers.

The question is separate breaker and relay panels - Snap, Foundry, Echo Feedthrough - or mains feed panels with both - Echo mains feed, Sensor IQ, Lyntech, Strand Contact Relay Panel, and others. Many variables to consider in deciding which way to go.
 
Instead of replacing the dimmer pack, why not put in a breaker box, and replace all the incandescent instruments with LEDs that dont need a dimmer, and then control them with that little orange box up there.
Well, before the proliferation of LED sources, I would offer an @STEVETERRY quote (from eleven(!) year ago:
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.
How well does that philosophy hold up in 2019?
I don't know anyone (except me?) who would advocate installing a Sensor3 SP6 pack with R20 or ThruPower modules, but... another quote (this one only six years old) :
A few points:

1. The key advantage to the ThruPower module is that it lets the end user put his/her hand on the "transition valve" that controls the rate of change between tungsten and solid state luminaires. And indeed this rate does need to be controlled by the end user, not the system designer or specifier. The function of ThruPower (dim or constant power)can be controlled from the console via the Net3 ACN link or from the ETC Concert application (also via the Net3 link). It is also memorized as part of the show file.

2. Tungsten and LED are going to coexist for quite a long time, making the function of the ThruPower even more practical.

3. Since the function of a circuit can and will change, even on a per-production basis, having different connectors for 120V dimmed and non-dimmed circuits does not make a lot of sense. Of course, 208V circuits must have a different connector rated for that voltage..

4. Since every circuit will sometimes need to support tungsten, keeping the 20A connector and circuit rating seems to make sense.

5. So, it's a tossup between 2P&G or L5-20, but I believe they should all be the same in a facility if they come from the dimmer rack..

6. Managing the settings of the dimmer rack for dimmed or non-dim on each circuit simply becomes another task for the production electrician. Following the mantra "Assume it's dimmed until proven otherwise" should minimize issues.
 
I agree but needs breakers.

If you go to LED, you might only need one circuit. Rule of thumb is 10 fixtures per circuit. Lots of exceptions but so maybe 2 circuits to replace 12 dimmed.

But not stated explicitly above - you need to depower LED fixtures when not in use. So relays usually.

But sufficient numbers of fixtures and most rudimentary infrastructure for a modicum of reliability and medium quality is thousands of dollars. Can you do that?

Thanks Ron for editorial help!
NOPE not at all. There is not interest in turning this space into anything other then what it is. And I have other spaces on campus worth fighting for. so 12 $ 500 apiece instruments purchased a couple at a time over the years is going to be the plan. Right now my fixtures are some ADJ silver par 64's all front light so the bar isnt very high to go anyway.
 
NOPE not at all. There is not interest in turning this space into anything other then what it is. And I have other spaces on campus worth fighting for. so 12 $ 500 apiece instruments purchased a couple at a time over the years is going to be the plan. Right now my fixtures are some ADJ silver par 64's all front light so the bar isnt very high to go anyway.

Not sure what part of post "nope" applies to but
12 $500 fixtures is thousands of dollars. One or two relays is not much.
 
Well, before the proliferation of LED sources, I would offer an @STEVETERRY quote (from eleven(!) year ago:

How well does that philosophy hold up in 2019?
I don't know anyone (except me?) who would advocate installing a Sensor3 SP6 pack with R20 or ThruPower modules, but... another quote (this one only six years old) :
Ya but know one is going to kick up the money for that kind of system here. And for just 12 instruments running in a straight line from House left to house right, that is a lot of machine
What is sad is I have a Sensor + 24 pack that was bought some 10 years ago I guess that was never installed because they cant ( physically cant, its a historic building) the proper power to it. I am going to have to surplus it out because I don't need it anywhere I can get power to it. I would love to install it and then just add R-20's modules. but it ain't happening
 
Not sure what part of post "nope" applies to but
12 $500 fixtures is thousands of dollars. One or two relays is not much.
Sorry, meant nope to this part. (But sufficient numbers of fixtures and most rudimentary infrastructure for a modicum of reliability and medium quality is thousands of dollars. Can you do that?) And the answer is no. not at all. I can swing purchasing a couple of instruments a year as long as their not to high end. The deal here is if I go for a new dimmer pack I have to find the money and facilities wont ever touch it. If we do a breaker box, they would pay for some of it, cost to install it, and service it. Your information on relays is incredibly helpful. that gives me a direction to research so thank you
 
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There may be an easier way.

The ETC Color Source Relay will work with your existing Show Baby transmitter. Hardwire the power to breakers and set the relays to turn on when DMX is present. It's pretty automatic relay control. You could then use your Show Baby reciever for show specific or floor gear, stuff that isn't permanently mounted. Also, several receivers reduces the risk of a wireless failure stopping the show.

This should let you convert slowly, as needed, using annual funds.
 
Look at wattage of the LEDs and see if they got on one circuit. I still think a relay is desirable but you could just wire it to a switch by the console. On the other hand, if you have DMX for the lights, there is a Foundry two zone relay that uses DMX do just pass through. Around $200. Still need one (or two) non- dimmed circuits.
I am very appreciative of the advise on the relay. It will solve a couple of issues and I should be able two swing it with my personal budget. so thank you
 
There may be an easier way.

The ETC Color Source Relay will work with your existing Show Baby transmitter. Hardwire the power to breakers and set the relays to turn on when DMX is present. It's pretty automatic relay control. You could then use your Show Baby reciever for show specific or floor gear, stuff that isn't permanently mounted. Also, several receivers reduces the risk of a wireless failure stopping the show.

This should let you convert slowly, as needed, using annual funds.
thank you slowly is the goal here. its either that or wait till enough stuff breaks/wears out that the next campus wide meeting is in the dark. which is a rotten idea thank you sir
 

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