# Control/DimmingPowering down LED circuits to lengthen fixture life

#### godlike2

##### Member
Background to this question...Our Music Concert Hall is getting its 24 ERS front lights, that use HPL 575 lamps, replaced with LED ERS fixtures. The front light is used during non-performance time (rehearsals and classes) and they were constantly burning out the HPLs by leaving them on for hours! Signs to turn off lights (trying to change the culture) and programming the lighting system to turn off at certain times didn't help. This space is not managed during the day but has public performances in the evening. If there are burned out lamps the faculty complain (even though they are responsible for the culture of use). Since HPLs are getting harder to find (consistently) and they are not cheap, I have been able to talk the administration into purchasing LED replacement ERS fixtures.

While talking with a theatrical lighting rep and the in house electricians, during a demo of LED house lighting fixtures and LED ERS fixtures, it was mentioned that the LED power circuits should be turned off whenever possible to extend LED fixture life span. The thought is that even though the DMX controller has "turned off" the LED fixture, the LED fixture is always connected to "constant power" and so its not the LED emitter that fails early but its the driver that fails due to heat derived from being always connected... and needs replacement before the emitter.

We have replaced our D20 modules, in the SR48 dimmer rack, with R20 and Thru Power modules, so to kill power to those LED circuits, the circuit breakers on those modules would need to be thrown in order to kill constant power. Having students or faculty going into the Dimmer closet and throwing circuit breakers is not a great idea. It seems like the answer would be a switch between the dimmer rack and the fixtures to disconnect those circuits? Thoughts...

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#### microstar

##### Well-Known Member
If you have remote panels to control the stage lighting system, you just program your R20 and TP20 channels to go to full in your stage presets and off with your off preset.
The switching power supply in the LED fixtures is particularly subject to AC power glitches and lightning issues, which having them on relays is good insurance when the system is not being used.
I have had an instance in two different venues where the switching power supplies in multiple LED fixtures were wiped out due to electrical glitches (one storm related and the other not).

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#### JonCarter

##### Well-Known Member
I amazes me that nowadays many people don't AUTOMATICALLY turn off ANY electrical device when they're not using it. (Or anything else, for that matter. Do they leave the water running 24-7 too?) Do they leave all the lights and everything else in their homes on when they go to work? Did they all grow up with parents who loved buying lamps and infinite utility bills? Granted: LED instruments use less power than conventionals, but they still waste equipment life and power if left on when not in use.

#### TimMc

##### Well-Known Member
I amazes me that nowadays many people don't AUTOMATICALLY turn off ANY electrical device when they're not using it. (Or anything else, for that matter. Do they leave the water running 24-7 too?) Do they leave all the lights and everything else in their homes on when they go to work? Did they all grow up with parents who loved buying lamps and infinite utility bills? Granted: LED instruments use less power than conventionals, but they still waste equipment life and power if left on when not in use.
My grandparents unplugged everything electrical when they weren't using it. I mean everything, Jon, except the stove and oven. Part safety, part preventive frugality.

But I don't turn off the main water valve to my house when I go to work, nor do I shut off the gas or pull my electric meter. And I leave some lights (LED, formerly CFL) on for security and convenience.

Now, should I get off your lawn, too?

#### JonCarter

##### Well-Known Member
Tim, I'll agree that unplugging the world and turning of the water main is a bit overboard, Unless, of course, ypur grandparents' house, and appliances were so poorly wired and plumbed that there were real safety hazards to leave things plugged in with no one watching them.

When I was in the service, every light switch in every building on post had a little sign over it: ON ONLY WHEN NEEDED, OFF WHEN YOU LEAVE THE ROOM. We need more such nowadays. How many kWH, or mWH, would we save every year, not to mention the CO2 produced in generating it?

#### RickR

##### Well-Known Member
As I spend more time in my RV, I'm getting advice like turning off the water when you go out for the day. Yes, RVs are that poorly built.

On the power side, in real terms electricity has become vastly cheaper and more reliable than 70 years ago. Remote (military) installations may not enjoy those improvements. The military is also not known for keeping abreast of the latest trends. Recent data suggests 5-10% goes to standby power, though individual power use is declining. https://green.harvard.edu/tools-resources/green-tip/eliminate-vampire-power This seems about 1% of world carbon emissions. There are moves to control standby power, especially plug loads by office workers, but the maximum gains are fairly small. Overall energy efficiency is the preferred target.

#### TimMc

##### Well-Known Member
As I spend more time in my RV, I'm getting advice like turning off the water when you go out for the day. Yes, RVs are that poorly built.

On the power side, in real terms electricity has become vastly cheaper and more reliable than 70 years ago. Remote (military) installations may not enjoy those improvements. The military is also not known for keeping abreast of the latest trends. Recent data suggests 5-10% goes to standby power, though individual power use is declining. https://green.harvard.edu/tools-resources/green-tip/eliminate-vampire-power This seems about 1% of world carbon emissions. There are moves to control standby power, especially plug loads by office workers, but the maximum gains are fairly small. Overall energy efficiency is the preferred target.
Yes, RVs are crap built. Workers typically are paid piece work and the unit moves to the next station on the line, ready or not, as scheduled. So I *do* turn off the city water to my RV, and I'll unplug from a campground pedestal if the power isn't 100%.

#### gbdesign

##### Member
RVs? I think we got off topic. The problem is, according to th OP , that people aren’t turning the lights off and by extension probably not the console either. So regardless that the non dim modules will cut power when no DMX is present, if no one turns the lights/console off, the LEDs will still be “on”. Maybe something like a motion sensor switch to turn off the signal if no one was in the space, but could be bypassed for performances. No idea if that exists.

#### Aaron S.

##### Active Member
The R20 and TP20 modules are DMX controllable like others have said. I personally don’t like the Park at full method. I like putting a hot patch curve on the channels in patch. But, that is purely personal preference.

#### RickR

##### Well-Known Member
Motion sensors can be added to almost any system, but have lots of unintended side effects.

#### Dover

##### Active Member
If the console has a real time clock function you could setup an [email protected] command to run at various times of the day like lunch and after hours. Just remember to disable it if you have a show.

#### coolsvens

##### Active Member
There are a few reasons to turn off your LED.
OFF- No light comes out but the fixture is still awake with power going to it. A minute bit of power is being used.
OFF OFF - Hard Power to the light has been turned off. No wattage be used.

Reason 1. It is helpful to turn OFF OFF your LED fixtures to save on some "vampire/phantom" energy draw overnight of .5w up to 8watts an hour sometimes adds up.

Reason 2. If you are just OFF, the fixture's electronics are still awake, the fan may be running, and all of those things will have potential failures before the actual LED emitters stop working.

Reason 3 (my personal favorite - Everything is a computer these days. I would argue the main reason to have an "air gap" relay so your are OFF OFF on your LED fixtures is in case there is a power surge, black out or other electrical issue, you will save yourself a huge headache by not blowing up the fixtures power supply. In the past if this happened you blew a $18/HPL lamp, not ideal, but totally fixable. Not the case with LED power supplies. #### Dionysus ##### Well-Known Member There are a few reasons to turn off your LED. OFF- No light comes out but the fixture is still awake with power going to it. A minute bit of power is being used. OFF OFF - Hard Power to the light has been turned off. No wattage be used. Reason 1. It is helpful to turn OFF OFF your LED fixtures to save on some "vampire/phantom" energy draw overnight of .5w up to 8watts an hour sometimes adds up. Reason 2. If you are just OFF, the fixture's electronics are still awake, the fan may be running, and all of those things will have potential failures before the actual LED emitters stop working. Reason 3 (my personal favorite - Everything is a computer these days. I would argue the main reason to have an "air gap" relay so your are OFF OFF on your LED fixtures is in case there is a power surge, black out or other electrical issue, you will save yourself a huge headache by not blowing up the fixtures power supply. In the past if this happened you blew a$18/HPL lamp, not ideal, but totally fixable. Not the case with LED power supplies.
Not to mention the most likely part to die in an LED fixture is not the LED itself but the driver. IF you power down your drivers, they last longer. But yes all good reasons!

#### Jay Ashworth

##### Well-Known Member
> Having students or faculty going into the Dimmer closet and throwing circuit breakers is not a great idea.

Correct, it's not.

We had an adjunct send a student into our dimmer closet to turn things off one day a couple months back. They turned off the 4 100A 3ph breakers that fed the 4 dimmer packs in the blackbox.

And then they went to the adjacent panel, in which they were supposed turn flip offf the 2 marked 20A breakers that feed the non-dims we use for LED and utilities on the catwalk.

They turned off *all 60* breakers in that panel. Taking out, among other things, the Ion and most of the other gear in our other (mainstage) booth. Luckily, it was just after 5pm, not just after that house's 8pm performance curtain.

There are now very prominent signs on that panel.

But to address JonC's point: it's actually not recommended to use standard circuit breakers as interrupting means; they're only rated for a limited number of handle flips. (I think I've phrased that right and no doubt Steve T will correct me if not .

#### STEVETERRY

##### Well-Known Member
> Having students or faculty going into the Dimmer closet and throwing circuit breakers is not a great idea.

Correct, it's not.

We had an adjunct send a student into our dimmer closet to turn things off one day a couple months back. They turned off the 4 100A 3ph breakers that fed the 4 dimmer packs in the blackbox.

And then they went to the adjacent panel, in which they were supposed turn flip offf the 2 marked 20A breakers that feed the non-dims we use for LED and utilities on the catwalk.

They turned off *all 60* breakers in that panel. Taking out, among other things, the Ion and most of the other gear in our other (mainstage) booth. Luckily, it was just after 5pm, not just after that house's 8pm performance curtain.

There are now very prominent signs on that panel.

But to address JonC's point: it's actually not recommended to use standard circuit breakers as interrupting means; they're only rated for a limited number of handle flips. (I think I've phrased that right and no doubt Steve T will correct me if not .
The only requirement for specifically-rated and marked breakers if they are used as switches is here:

240.83(D) Used as Switches.
Circuit breakers used as switches in 120-⁠volt and 277-volt fluorescent lighting circuits shall be listed and shall be marked SWD or HID. Circuit breakers used as switches in high-intensity discharge lighting circuits shall be listed and shall be marked as HID.

ST

#### Jay Ashworth

##### Well-Known Member
Would I be correct, @STEVETERRY, in assuming the marking in question would be on a side label, where you need to at least pull the panel, and possibly unship some breakers, to confirm?

#### STEVETERRY

##### Well-Known Member
Would I be correct, @STEVETERRY, in assuming the marking in question would be on a side label, where you need to at least pull the panel, and possibly unship some breakers, to confirm?
That would be a reasonable assumption, especially for a single-pole branch breaker. But many mainstream breakers (Square D type QO, for example) are switch-rated per 240.83(D). But remember, no fluorescent loads or discharge loads?--no prohibition against using it as a switch, even if it is not rated or marked as such.

ST

#### derekleffew

##### Resident Curmudgeon
Senior Team
Hmmm, I vaguely recall a shop person quoting his boss, the owner of an NYC lighting company, something along the lines of
"That's a <expletive-deleted> circuit breaker, not a <expletive-deleted> switch!"
referring to the main on a rolling dimmer rack or moving light distro.

#### STEVETERRY

##### Well-Known Member
Hmmm, I vaguely recall a shop person quoting his boss, the owner of an NYC lighting company, something along the lines of
"That's a <expletive-deleted> circuit breaker, not a <expletive-deleted> switch!"
referring to the main on a rolling dimmer rack or moving light distro.
Sounds familiar.

ST