McCready00
Active Member
At what temperature do you think it gets bad to use moving fixtures outside? Let's say it's a touring events, all concerts are outside, and the equipements are staying at the cold during the driving.
Touring during winter.
- Thread starterMcCready00
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Well... the extreme side would be the LCDs will eventually freeze and components will crack from the extreme contraction.
On the more likely-to-be-seen side, I've seen photos of HES fixtures running in snow. I'd say definitely allow extra time for checks because the cold could cause problems with just about everything, but the fixture itself is a nice little heater, so once it warms up it should be fine. I'll defer to Ship for the final say on this, but I'd think the arc would take a little bit longer to stabilize in extreme cold.
I'm curious what some of the people on here who've used them in the cold will say. Does the extreme cold (I'm talking about below freezing) negatively impact the fixture's long term reliability (b/c of great thermal stress/ micro-fractures)? How long is the usual warm-up cycle in cold environments? Do the motors/gears/ internal bits need a warm up period because of lubricants freezing and unequal contraction of components?
On the more likely-to-be-seen side, I've seen photos of HES fixtures running in snow. I'd say definitely allow extra time for checks because the cold could cause problems with just about everything, but the fixture itself is a nice little heater, so once it warms up it should be fine. I'll defer to Ship for the final say on this, but I'd think the arc would take a little bit longer to stabilize in extreme cold.
I'm curious what some of the people on here who've used them in the cold will say. Does the extreme cold (I'm talking about below freezing) negatively impact the fixture's long term reliability (b/c of great thermal stress/ micro-fractures)? How long is the usual warm-up cycle in cold environments? Do the motors/gears/ internal bits need a warm up period because of lubricants freezing and unequal contraction of components?
There are plenty of winter sports out there that have automated lighting, Its not a huge issue. However, I would approach it like a diesel engine in the cold. If you can get is started, leave it running. All of these fixtures do have min. operating temperature. I would be more worried about glass cracking with a fast heat change and stuff like that. I don't think it would be the greatest thing for them.....
the simple anwser is it depends on what the manufacturer has stated in their data sheet for the fixture
The more complex answer as to what happens at temperature extremes: is it depends on the circuit design and the grade of electronic components, board material wiring etc used to manufacture the fixture. The performance and reliability of electronic components is temperature dependant: resistance of a resitor decreases with temperature and the gain of a transistor increases as the temperature decreases - important because all integrated circuits are made doping the semiconductor wafer to create thousands of transistors. All of these variables result in gain drift in circuits which can result in circuits oscillating, voltage errors, switching threshold voltages not being achieved etc. etc. The design engineer can analyse how the circuit performs at the extremes of temperature and supply voltage and implement circuit modifications to address problems arising because of wide operating temperature ranges - unfortunately this comes with a cost which is why manufacturers provide a maximum operating temperature range and in many cases a non operating temp range.
The general rule of thumb is the more expensive grade of components that must be used the more expensive the manufacturing costs will be. Most commercial electronic components have a temperature range of 0 degrees centigrade to + 70 degrees centigrade, automotive components are available with temperature ranges of -40 degrees centigrade to +125 degrees centigrade, military components are available for -55 degrees centigrade to +125 degrees centigrade and there are other temp ranges available. However just because a component data sheet provides guaranteed performance specs over these temperature ranges does not mean that the circuit will work over these ranges.
while equipment that stops working correctly because you have exceeded the maxim operating limits will perform correctly once the temperature returns within the correct range the same is not true if you exceed the maximum non-operating temp ranges. this may cause physical damage to equipment becuaes of differences in the temperature coefficient of expansion between the materials used in the manufacture of the equipment: solder joints can crack due to stresses, cracking of the seals on component packages etc.
Also note that when turning on cold equipment that is below the cold operating limit circuits that include crystal oscillators may not work because the crystal oscialltor may refuse to oscillate a specification called the: cold start temperature - just warming it up will eventually cause the oscillator circuite to function.
The more complex answer as to what happens at temperature extremes: is it depends on the circuit design and the grade of electronic components, board material wiring etc used to manufacture the fixture. The performance and reliability of electronic components is temperature dependant: resistance of a resitor decreases with temperature and the gain of a transistor increases as the temperature decreases - important because all integrated circuits are made doping the semiconductor wafer to create thousands of transistors. All of these variables result in gain drift in circuits which can result in circuits oscillating, voltage errors, switching threshold voltages not being achieved etc. etc. The design engineer can analyse how the circuit performs at the extremes of temperature and supply voltage and implement circuit modifications to address problems arising because of wide operating temperature ranges - unfortunately this comes with a cost which is why manufacturers provide a maximum operating temperature range and in many cases a non operating temp range.
The general rule of thumb is the more expensive grade of components that must be used the more expensive the manufacturing costs will be. Most commercial electronic components have a temperature range of 0 degrees centigrade to + 70 degrees centigrade, automotive components are available with temperature ranges of -40 degrees centigrade to +125 degrees centigrade, military components are available for -55 degrees centigrade to +125 degrees centigrade and there are other temp ranges available. However just because a component data sheet provides guaranteed performance specs over these temperature ranges does not mean that the circuit will work over these ranges.
while equipment that stops working correctly because you have exceeded the maxim operating limits will perform correctly once the temperature returns within the correct range the same is not true if you exceed the maximum non-operating temp ranges. this may cause physical damage to equipment becuaes of differences in the temperature coefficient of expansion between the materials used in the manufacture of the equipment: solder joints can crack due to stresses, cracking of the seals on component packages etc.
Also note that when turning on cold equipment that is below the cold operating limit circuits that include crystal oscillators may not work because the crystal oscialltor may refuse to oscillate a specification called the: cold start temperature - just warming it up will eventually cause the oscillator circuite to function.
Other than say the Winter Olympics, which is more of a temporary install than a tour, I can't think of many instances where the exact situation you describe would arise. Most audiences don't like being exposed to the cold elements during a concert.
A check of Pollstar shows many tours in cold climates where gear travels overnight in unheated trucks then is used indoors. One would hope the gear naturally has a chance to acclimate, and is not unloaded from a truck and immediately powered up.
There are stories on many forums of people using moving lights outdoors at 0°F or below. They usually leave them lamped on the entire time they are exposed, and often write an automated cue sequence that exercises all motors once an hour minimally.
We have plenty of outdoor concerts up here during the winter, especially at the ski resorts, this actually comes up more then you think.
Really, the worst thing about working outside in the cold is dealing with cable. Multi cable can heat up and melt into the snow/ice. Try to get that back in a nice coil after that happens....
Really, the worst thing about working outside in the cold is dealing with cable. Multi cable can heat up and melt into the snow/ice. Try to get that back in a nice coil after that happens....
Barbarians
Seconded on the cold multi. Even when doing an indoor ice show, never let it touch the ice. Wonder were Porkchop has been?
Barbarians
Seconded on the cold multi. Even when doing an indoor ice show, never let it touch the ice. Wonder were Porkchop has been?
Not all of us live in an area that is naturally inhabitable...
shiben
Well-Known Member
Well, we dont have to pipe all of our water in from other places, but thats a different story i guess...
Having worked many ice shows, it makes things more difficult but not impossible. Coiling cable is the worst part no doubt. I also outdoor events in fairly cold conditions and really never had an issue. We do Punkin Chunkin i DE every year and it ranges from not too bad to burtal cold.
Some of us folks have to cut blocks of ice out of the lake and melt it ;-))) (a bit more north than I am)
One of the issues to be careful of is condensation build up, In some areas that have low temps but also high humidity this can be a problem. As an aside it is magical to see the ice crystals grow sometimes to over an inch over night where there are low temps but still a lot of moisture in the air which then as the temp drops the moisture is forced out into crystals
http://maineowl.net/blog/media/1/20090127-winter_26.jpg
Sharyn
One of the issues to be careful of is condensation build up, In some areas that have low temps but also high humidity this can be a problem. As an aside it is magical to see the ice crystals grow sometimes to over an inch over night where there are low temps but still a lot of moisture in the air which then as the temp drops the moisture is forced out into crystals
http://maineowl.net/blog/media/1/20090127-winter_26.jpg
Sharyn
GreyWyvern
Well-Known Member
Barbarians
Seconded on the cold multi. Even when doing an indoor ice show, never let it touch the ice. Wonder were Porkchop has been?
Porkchop may be lost to the rat as a POWD.
When I was with Feld on a DOI show, we would make it a point to not let cable lay on the ice, especially the 4/0.
We were somewhere in Malaysia (I think Penang) and when we came into the arena the next day after load in and fired up the rig, all of the studio spots and studio colors dumped a good cup to 1 1/2 cups of water out as they homed!:shock: Suprisingly, we only lost 2 or 3 units. We had them back online later in the day though.
High School Musical last I recall.
GreyWyvern
Well-Known Member
That might be the answer to what became of him. I know that would make me want to give up on life!
masterelectrician2112
Active Member
If anyone watched the winter x-games you might have seen the small rig at the top of the gigantic ski jump. I have no idea what the temperature is there, but all of the fixtures were operating fine. The lights looked pretty darned cool on the snow, too!
