Mac Cool Down Time

[tom_the_LD]

Did you speak to the hire company about the lights? I know it's a pain swapping fixtures out but it could have meant 4 new fixtures ready for tonights and tomorrows shows - obviously it's a bit late for that now.

 

Pan and tilt working would say that it isn't them being unplugged - because then nothing would work!

[CharlieH]

Did you speak to the hire company about the lights? I know it's a pain swapping fixtures out but it could have meant 4 new fixtures ready for tonights and tomorrows shows - obviously it's a bit late for that now.

 

Pan and tilt working would say that it isn't them being unplugged - because then nothing would work!

Yes, I guess that would have been sensible! :D

Out on a limb here but could the lamps be nearing the end of their life and dousing themselves because of that.

I've thought more about that, and it's unlikely that all 4 movers are coming to the end of their life at the same time, isn't it?

 

I'm stuck for ideas now! Unless the desk is malfunctioning somehow, but then it didn't happen in rehearsals, hence why I don't think it's a dodgy program!

[iamchristuffin]

Out on a limb here but could the lamps be nearing the end of their life and dousing themselves because of that.

I've thought more about that, and it's unlikely that all 4 movers are coming to the end of their life at the same time, isn't it?

 

Not completely impossible if they were all replaced at the same time.

[Guest lightnix]

...set DLOFF to OFF in the PERS menu...

This would be my guess, if they were all lamping off together. That way, if something had somehow got into the programming (the way it can, sometimes), doing this would ward off the effect.

 

If the fault is being caused by temperature, then you should get bTER (Base temperature error) or HTER (Head temperature error) in the display. If you're not getting that, then it's not the temperature.

 

 

As a general tip, one of the first ever fault-finding lessons I was taught, was...

 

It's highly unlikely, that more than one light will develop exactly the same fault, at exactly the same time.

 

This is especially true, where more than one type of light is affected.

 

 

Run through the cues, step by step - including any stuff you might be doing, that isn't in the memories. Keep a close eye on the monitors and watch the outputs - if you see the first channel on the affected units hit a level between 248 - 255DMX or 97 - 100% then there's your problem. Do it with the lights switched off at first - that will help you concentrate on what's going on in the desk. You might find that you unwittingly had those channels raised when you edited another cue; or accidentally included them in a group of generics; or something like that. It doesn't mean you're a rubbish programmer, we've all done it at some point :D

 

If you can't find it, then do what djandydee suggests and disable the DMX Lamp Off function.

 

For quick reference.

MAC 500 manual (PDF)

MAC600 manual (PDF)

 

 

 

e2a... If you can limit the outputs on the relevant channels to 246DMX / 96%, that might also provide a cure.

[Ynot]

Out on a limb here but could the lamps be nearing the end of their life and dousing themselves because of that.

I've thought more about that, and it's unlikely that all 4 movers are coming to the end of their life at the same time, isn't it?

 

Not completely impossible if they were all replaced at the same time.

Impossible? No

Likely? VERY UNlikely, to be frank.

[tommulliner]

Have you tried before the show going through every cue in the stack in order? Does it do the same thing as has been happening in rehearsals? If not, It must be a time thing with temp etc. but if it does do the same thing, it will be a programing fault. - and Dependant on how much time you have, I would try to re program the last few cues. (and then check them a few times of course!)

[CharlieH]

Ok, thanks everyone. I will run through my cues when I get in tonight, and check. It is not going to be easy to access the 500s as they are mounted on a bar, but the 600s I can disable the lamp off command. I think I agree with you though, it could be a program fault. I will check tonight.

Thanks for everyone's help, much appreciated and nice to know that I can get help if needed!

Charlie

[Grum]

Hi Charlie,

 

Unless you're getting the bTER or HTER error messages, as Lightnix as already suggested, you need to forget about ambient temperature being the cause of the problem. To give you an idea of the sort of abuse a Mac 500 can take. I've used them on a festival in Australia where the ambient temperature inside the hall at ground level was around 45C, so hot that the crowd were passing out. In these conditions we had several Mac500's along with loads of other moving head units, 40 odd strobes and even more blinders (all hot units) and we never had a unit fail due to heat despite the whole rig being switched on and functioning without a break for around 12 hours.

 

The fact that the other functions are still working proves they still have power but doesn't prove that the power hasn't been switched off, possibly by someone that doesn't know they're doing it.

Do you have to send the units a lamp on command or do the lamps ignite when you switch them on? If they lamp on automatically and are somehow loosing power then you will get a HOT error message this tell you that the unit must have lost power because it is going through it's initial start up, trying to strike the lamp but failing because the lamp is too hot.

 

Auto Lamp on not being selected means there are realistically two likely causes.

1. The units are loosing power somehow during the show then not recieving a lamp on command. However this would cause the lound reset noises which you don't seem to have experienced until you tried to reset the fixture.

2. There is a bug in the program somewhere that sends the lamp off command. We all get bugs in our programming sometimes, I've made more screw-ups in my programs than I care to remember. Learning how to recognise them takes time, finding them take less time and fixing them can be so quick you'll be kicking youself.

[Guest lightnix]

The quoted operating temperature range is simply that within which the equipment is guaranteed to function, as described and under the terms of the warranty.

 

It's pretty inevitable, that equipment will be exposed to higher temperatures that this from time to time and most pro kit will survive this in the short term - if you keep the airways clean. However, the long term effect will be to shorten the life of the gear - something to be borne in mind when speccing permanent installations.

 

As a general rule, the warmest part of the volume above the stage, is the over the centre. The coolest is usually over the door(s) to the dressing rooms and other parts vary, according to the design of the building.

[Wilflet]

The fact that the other functions are still working proves they still have power but doesn't prove that the power hasn't been switched off, possibly by someone that doesn't know they're doing it.

 

Thats what I was thinking too.

 

Are the units on dedicated lighting power or do they share with anything else?

 

The interval is going to cause spikes in power demand for some things in the building, think beyond the house lights, think tea urns, hand driers in the toilet, assorted bits and pieces in the dressing room.

Is it possible that your using a general use ring main for the movers, the tea urn has gone on, taken out the trip, including loosing power to the heads, and the person in there has reset a trip and not thought to bother anyone with the fact power went, after all it probably always does that and as far as they know it dosnt effect anything else, at which point your heads are back on and unlamped.

 

Things like this probably wont come up in the rehearsal as you will most likely skip over the interval straight into act 2 scene 1

 

not saying that is exactly what happened, but its always worth thinking what your share power with.

[Guest lightnix]

If the power had been switched off, then they would go into reset when it come back on again - hardly something that would go unnoticed

[Wilflet]

If the power had been switched off, then they would go into reset when it come back on again - hardly something that would go unnoticed

 

Its the interval, its not unheard of for the lampy to go for a slash, a cup of tea etc. With enough crowd chatter/movement I don't think it will be noticed.

[slipstream]

Sounds like the story in Intensive Care where bed one had the highest fatality rate, they then discovered the cleaner plugging the floor buffer int the socket beside the life support machine. Not true I am sure but I would be watching for the talent getting the tongs out and using your mac plug point

 

Sam

[CharlieH]

Sounds like the story in Intensive Care where bed one had the highest fatality rate, they then discovered the cleaner plugging the floor buffer int the socket beside the life support machine. Not true I am sure but I would be watching for the talent getting the tongs out and using your mac plug point

 

Sam

Haha, fair point everyone, except the movers work for the first few scenes in Act 2. It starts with a jail scene, and I have gobos in both movers. I would definitely notice if this didn't happen, and it always does. Hence the problem has to lie between Act 2 Scene 1, and (for those of you who know the play) Motormouth's song 'I know Where I've Been' as that is where I noticed the problem.

 

The more I think about it, the more I think it will be a programming error introduced when I edited the stacks, after the rehearsal. I am going in very early today to run through my second Act stack without any signal being sent (I will probably unplug the DMX leads form the back of the desk), monitoring the screen for a Lamp Off command. I can then edit it for this evening's performance. I hope that works, if not - I will just have to reset them in performance again.

[niclights]

I hope that works, if not - I will just have to reset them in performance again.

You don't need to reset - just send a lamp on. Time between douse and cold restrike will be around 5-8mins.

 

For reference a fixture will normally be reasonably cool approx 20mins after lamp douse with fans running.