Control/Dimming Non-Permanent Shutdown Procedures

Portable: Do you remove power from dimmer racks/PDs at night?


  • Total voters
    64
Re: shut down pros and cons

Yes, it's relatively secure.
The only power issue I've had is one instance of severe thunderstorm and lighting activity which scrambled the dimming. There will be precautions against this happening again.
 
Re: shut down pros and cons

I selected "other" because it is situation dependent. Back in the days of Vari-Lite VL-2's VL-4's VL-5's and VL-6's we would generally leave everything powered, but lamped off, because the power up procedure is the hardest on the fixtures, and a shutdown would mean hours climbing in the truss the next day. These days.. big TV shoots (Emmys, Grammys, MTV video awards, Olympics, etc... ) we leave the system on for the same reason..... otherwise we shut down due to liability issues of an unattended system.
A note.... Shutting down to let the fixtures cool does nothing to help the fixtures, and is in fact detrimental.... Having discussed this issue with engineers at Vari-lite, PRG, and Morpheus, all stated that the thermal cycle from going from off to operating, and vise versa, is the hardest on the electronics. This is a known phenomena, and there are in fact reams of technical literature discussing ways to mitigate the issues of power and thermal cycling. (Just google thermal cycle power on off) for some ideas of the tech literature)
The advantages to shutdown:
Fans off= quit sucking haze and dust into the optics and electronics
reduced risk of problems due to power issues (lightning, dropped leg)
less chance of marginal connections overheating
fixtures won't get damaged if something interferes with their pan/tilt (motor doesn't run all night trying to get into position)
The disadvantages to shutdown:
increases the chance of component failure in fixtures
which results in more time/expense in daily upkeep of fixtures

Hope it helps
RB
 
Re: shut down pros and cons

I think dimmers can be left connected, as long as the channels are down (except for house lites, required safety stuff, etc.). Moving lights etc., I don't see the point of leaving them on. It's been said that lamp strikes cause anywhere from 1 - 10 hours of lamp deterioration. If that's true, then if the fixture is not being used for that time or longer, shut them off. And as LED fixtures move more into the mainstream, it seems that the fixture will be obsolete before the diodes need to be replaced, so shut them off to save electricity (fans, etc.).
 
Re: shut down pros and cons

Martin's manual for the HID moving lights I own quotes that a lamp strike will take 1 hour of life off the lamp. If a fixture will sit for 45 minutes I'll leave it on. Likely I'm probably going to leave the lamp on even if it is to spend 2 hours sitting. Much beyond that and everything is probably going to get completely shut down simply to save on energy costs. With modern fixtures there is no realistic reason to waist the power to leave them on (even lamped off) for 24 hrs, its simply a waist of power. Computer monitors draw 25 watts continuously in power save mode and that isn't powering much, think about what a moving light draws continuously with all of the transformers and electronics that are always powered. And if you have older fixtures that have continuous run fans (instead of the newer temp sensor based fans) you're wasting that much more, and feeding that much more dust through the fixture.
 
Re: shut down pros and cons

I voted never because if I had my choice I would never shut power off, but in reality if we're running on generators we shut down power at night because fuel is expensive. That being said, equipment that's on the road usually has a rough enough time making it to the venue and powering/homing up properly once. Doing it every day usually ends up in driver boards and sensors that need to be replaced more often. Also if you are in a situation where you're limping equipment along (as I've run into several times waiting for parts) it's certainly preferable to get a unit into a usable state on the ground and leave it there rather than have to climb and mess with it every day.
That being said I've run into a few building guys (especially in the UK) that are very confused as to why we "waste the energy and fan life" to leave the lights on all night long. Our usual response is you just don't get it and we're paying for it so just go with it........

EDIT AFTER I READ THE ENTIRE THREAD: There is most certainly a point to leaving a piece of touring equipment powered on but lamped off for short runs (say less that 7 days). As RonaldBeal said powering on a light is one of the hardest times on the electronics. Once you get a your rig homed properly the last thing you want to do is anything that will cause a pieces of the rig to rehome yet alone the entire rig as happens with a power cycle. It doesn't matter if it's rental equipment or equipment you own there's going to be a point where things don't recalibrate correctly on their own, and the worst time to find that out is when you arrive in the morning before a long day of shows. As far as wasted energy and fan life go, I've never seen a moving light rig use a very notable amount of power to keep the electronics and fans running (usually less that an Amp per fixture). Also most of the fans I've replaced over the years where damaged significantly more by heat (both normal wear and being powered off while the fixture was still VERY hot) than they where from wear and tear from being run 24 hours a day from load in to load out. Lastly I work for a company with several shows with a whole lot of fixtures and they've been doing it for quite a while, and our policy from the top of management is power on if at all possible, it's not like some serious thought hasn't been put into that over the years.
 
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Bringing this one back from the dead. Is there a NEC code justification for having to shut down temporary power when the building is un-occupied? I can't find one.
 
Bringing this one back from the dead. Is there a NEC code justification for having to shut down temporary power when the building is un-occupied? I can't find one.

Have you spent the past 11 years searching ?
 
Not even sure how I'd do that. The only time I dabble in this world these days is the local HS's spring musical. I've got access to the board and rack, but that's it. No clue where the breakers for the rack even are.

I will say modern gear seems to like being power cycled occasionally, as anything thats crashed in software up will reboot. That's why a help desk's first solution it to power cycle the machine. On the 2yr old system at the school, I had 2 lights go out this year. 1 fixed by unplugging and replugging it. the other non-responsive even after being swapped out and plugged into a wall outlet. The board(ECT Ion XE) installed also crashes nearly every time it's shut off....

Somehow I feel the system won't have near the longevity of the previous systems(1992, ~2001, 2008, ~2021.) I have mentioned my mentality that they should be spending half as much money twice as often, i.e. upgrading the system to address weaknesses every 4-5 yrs rather than a full on upgrade every 10-12), with the response that it's feast or famine, i.e. all or nothing. I had to fight to preserve as much of the old system as possible, knowing I can keep it going so long as a few basic parts are available, whereas the new LED fixtures will need to be sent out for repair every time, as I'm not willing to tear into them until well past any warranty period, and only maybe, then.

I will say I do wish moving lights wouldn't go into a self test mode when they first receive power, as the position with the dead light I mentioned, and it's counterpart on the other side of the house have a moving light in the bottom position and daisy chained through other fixtures and are only accessible via a step ladder between rows of seating. Disconneting power to US lights means quickly plugging something in, climbing down the ladder, and tilting it out of the ML's range to operation.
 
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It makes sense to me, as
Bringing this one back from the dead. Is there a NEC code justification for having to shut down temporary power when the building is un-occupied? I can't find one.
It makes sense to me, although "temporary power" basically means extension cords. I will say in the industrial setting I work in, extension cords get more use when the place is unoccupied than when it is.
 
Have you spent the past 11 years searching ?
Lol. Nope. Trying to get an idea killed... so seeing if there is a code reason for this vs a good practice decision.
It makes sense to me, as

It makes sense to me, although "temporary power" basically means extension cords. I will say in the industrial setting I work in, extension cords get more use when the place is unoccupied than when it is.
When I say temporary power I mean this... (not my picture, first image that popped up when looking for "dimmer beach".

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Bit of an odd source, but my day job used to be with a major construction company that has a T&D division and industrial electrical division. Rather than futz with generators and welders, every job would just get a meter installed and then temp power distros from there, sometimes out on a half mile of crane trestle, docks, shore power to barges, etc. I'd let these guys build distros for me any day, absolutely top quality people and attention to detail. The Code is their bible.

I don't recall even a passing mention of a requirement to de-energize temp power (on wet, metal objects) when the site or structure wasn't occupied. I have never heard of it in production or construction

Personal preference, maybe, but not Code.
 
As an arena electrician... usually only by specific request of the show department or PM once I've energized a service, until load out. Too much stuff wants to maintain status or charge or... whatever needs some electrons over night. Outdoors or outdoor exposure? That's part of the Safety Chain that occurs before I'm involved, usually.

As you point out, practice is not Code. Guess I need to take a better look into 525... or wait for Steve T to arrive. ;)
 
When you consider that there is little functional difference between a touring 96 rack and and an install 96, excepting the touring rack has wheels, and that we do not power down install racks, my take would be there is no valid reason to power down the touring system. I would if requested by the touring electricican.
 
As an arena electrician... usually only by specific request of the show department or PM once I've energized a service, until load out. Too much stuff wants to maintain status or charge or... whatever needs some electrons over night. Outdoors or outdoor exposure? That's part of the Safety Chain that occurs before I'm involved, usually.

As you point out, practice is not Code. Guess I need to take a better look into 525... or wait for Steve T to arrive. ;)
ST reporting for duty.

Generally, permanent equipment is located in access-controlled rooms. Portable power distribution gear is not. If unqualified persons gained access to the portable equipment, there is a real potential safety issue, IMHO.

No specific NEC requirement to do so, but I think it makes sense to power down portable gear when not supervised by qualified personnel. Plus, in 2023 there is the vampire power consideration.

ST
 
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Bringing this one back from the dead. Is there a NEC code justification for having to shut down temporary power when the building is un-occupied? I can't find one.

The NEC does not govern anything beyond the permanent fixed electrical installation. Cord & plug or, connectorized utilization equipment is governed by local building codes and vary depending upon the use/ occupancy of a building or structure. Loosely translated that means I can plug 6-way adaptors into every duplex receptacle in my house and run 6 things at once, drape extension cords over curtain rods, and put a 250-watt heat lamp bulb into my bedside lamp socket. Smart? No... but an electrical code enforcement officer or authority having jurisdiction could not "violate" it. But would likely notify the buildings or public safety department which in some areas is the very same person anyway.
 

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