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LMI dimmer rack

Discussion in 'Lighting and Electrics' started by domiii, Mar 28, 2007.

  1. domiii

    domiii Member

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    OK, my community theatre has a LMI/ETC 1.2k 24 circuit dimmer rack. I was always told when powering up and shutting down the rack to turn off or on the individual circuit breakers on each dimmer card and then the main breaker.


    Well someone told me that by using the individual circuit breakers as 'on - off' switches I am weakening the breakers and it is better to leave them on and just turn off the main.


    What is the general consensus? Will using the main breaker as a power on - off switch cause a 'spike' and damage the rack?
    Thanks in advance for your advice.



    PS: We are hoping to upgrade to a 48 circuit ETC Sensor rack in the near future. I can't wait!
     
  2. Van

    Van CBMod CB Mods Premium Member

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    How often are you powering up and down the whole rack? It really shouldn't "weaken" the breakers unless you are "snapping" them off ie, just going down the rack flicking them off. The only weakening that would occur in that situation would be to the plastic handles and framing of the breakers themselves. Generally it should be ok to use the mains for powering up and down as long as there is no load on the individual dimmers. If they are unplugged there shold be no prob.if they are plugged you have a potential for spikes.
     
  3. icewolf08

    icewolf08 CBMod CB Mods

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    Why do you power your rack up and down? In theory you shouldn't have to turn the entire rack off unless it is portable and you are moving it, or for service/maintenance. If your control console is off and the dimmers are off, the rack will only draw enough power for it's controller, so if you are concerned about electrical usage, a powered up rack with no active dimmers only draws a nominal amount of power.
     
  4. TimMiller

    TimMiller Well-Known Member

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    Over at theater's and such the dimmer racks are powered up 24/7. The racks are never shut down, and its actually better on the circuitry to stay on. The brains do have some built in surge suppression and most buildings have some form of surge suppression on them if it is a surge problem they were worried about. But i bet no one told you that every time you turn the main breaker on it does get an initial surge of power. And the heating and cooling effects on the pcb from being powered on and off is not good for it. I work on 20+ year old strand racks that have never been powered down. Also when shutting off the main there is no reason to turn off each individual circuit on each dimmer. The main will kill everything. No reason to put extra wear and tear on the individual breakers. Also mains are not too fond of being thrown on and off everyday. Only thing it turn all the breakers and main off on is our moving light pd (its a road rack) when it gets to a new show. So i can turn on the main at first if nothing blows up then procede to turn on one breaker so i can meter the power, and then go ahead and start powering up each bank of lights. But after the first show at the building they are at i just turn the main on and off.
     
  5. domiii

    domiii Member

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    We do not run the house lights through the rack and we only have shows on Friday, Saturday and Sunday matinee. There can be up to three weeks between shows so we have always powered them down.


    This is an old touring rack that only has one fan in it. The serial number on the controler card is less than 50 so we are talking about an old card so we want to treat it as gently as possible.


    Is it really better to leave it on all the time?
     
    Last edited: Mar 29, 2007
  6. Van

    Van CBMod CB Mods Premium Member

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    Six of one half dozen of another. After working with production rental house for years I can state with a bit of authority that I never had a control card, dimmer module, or Breaker break beacause of the almost daily cycle of being turned of and on at the mains. That inludes Lep's, NSI's, EDI's, ET's, ETC's, yaada yaada yaada. I'll stand by what I posted earlier. The Only issue I can see is that since you have stated that it's an old rack, I'd suggest you keep that fan very clean, Blow out all the components and keep them dust free. A fan that old is going to wear out from being on constantly much quicker than a brand new 100k hour MTBF fan.
     

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