Laser scan rate

[Stripey]

Hi, this is my first post by a laser newb....please be gentle.

Is there a way to 'cap' the scanrate?.....I thought it was easy as leaving at 30,000 in Projector settings (I have 45,000 Cambridge galvos)
I foolishly loaded 3D Ball frame file, galvo's went crazy and blew a fuse on the lower paddle.....not a good start to my introduction to pangolin.
What have I done wrong?.....apart from my system not being 3D.....I would have thought that something would be in place to stop this overscanning that has wrecked the galvo.....and how to I know which frames or frames in shows are going to result in the same?
Many thanks .

 

[Aaron@Pangolin]

I am sorry to hear you experienced a problem with your scanners.

In LD2000 the default scan rate is 30kpps but you can change it to as high or low as your want (between 5k and 120kpps). The default scan size is 100%... I strongly question whether it was the default scan speed of 30kpps that caused this to happen to your scanners; I suspect the correct scan angle was not calculated and set before trying to display this frame. I can envision a problem if you tried to project this frame at 100% scan size as that would probably be well over 60 degrees. (My 6215s run at 25 degrees at 30% scan size in LD2000)

The ILDA scan angle standard is 8 degrees and most of the 6215s I have seen in use can project the ILDA test pattern at 15 to 20 degrees at 30k (mine can do it at close to 25 degrees); if you tried to display the 3D ball at 30kpps AND at 100% scan angle then this might have been the cause of your issue. Changing the scan size to a value that drives your scanners at 8 degrees should be done when you first start using any laser controller package. Here is a web page we created to help make this calculation: http://www.pangolin.com/userhelp/scanangles.htm.

Luckily you do have Cambridge scanners and only need to replace the fuse they have installed to protect them from over driving situations like this; I doubt the scanner with the blown fuse is "wrecked" but our local "scanner expert" can look them over if you would like to ship the set to us for review.

 

[Stripey]

Thanks for the reply Aaron.
I'll have a read and try to understand.
.....Quite.....'wrecked' was the wrong term.....bit rough around the edges me.
I'm very intro level, and don't use for hire purposes, more for an art display/UV Faerie Garden, and should highlight my positive knowledge of the safety aspects of such equipment (3.5w White)
You nearly lost me at scan rate, then you muddled it up for me with beam angle lol.
I'm just about struggling through creating frames, and capable of editing pre-existing shows, so that side of it, i'll suss.....it's the more techy side that leaves me lost if I'm honest.
I truly thought it would be sort of plug+play, which through luck it seems, on the whole it has been.
Stripey

 

[masterpj]

When creating graphics or loading graphics you have never loaded before a rule of thumb is always to start at a small angle and size up afterwards.. there are people who create graphics which are not very sparing on your galvos and this is likely what happened to it.

Some of the very old graphics with LD2000 are extremely hard on galvos so there is little headroom left when overscanning or scanning large angles with these graphics.

Hope that helps!

 

[Pangolin]

The 3D Ball frame is certainly a very old frame. Perhaps 25 years old... It was made back in the days of moving iron galvanometers, which were generally more robust and more "fault tolerant" than moving magnet scanners. The ball can be displayed by modern projectors, but not likely at "full size", and certainly not faster than 30K almost regardless of the type of scanners you have.

I'll also say (and I hope most people will agree) that I am a scanner expert. When all equipment is functioning 10000000% correctly, nothing should ever blow a fuse. (For example, there should be nothing that the user can do that will cause their hard drive to catch on fire.) And so your report tells me that *something* within your greater system isn't functioning correctly.

And finally, I will say (and again, I hope most people will agree) that I am somewhat of an expert on Cambridge scanners, and with that being said, Cambridge actually doesn't even make "45,000 galvos", nor anything even remotely having that kind of name. For that reason, I will make the broad assumption that you have been *sold* something (hey, buy this projector because it has Cambridge 45,000 scanners), but the reality is that you probably have Cambridge model 6210 scanners (which are nominally 30K scanners, but will go faster under certain circumstances), but I assume that (unfortunately) your 6210 scanners are driven by something other than Cambridge servo drivers. Personally, knowing nothing more about the situation, I am making the assumption (which I think everyone will agree is dangerous) that your driver is not really functioning 100000000% correctly, didn't have the right fuse, didn't have the correct "coil temperature calculator" settings, or the like, and THAT'S why the fuse blew.

LD2000 is our older-generation software. Since the release of that software more than 16 years ago, our development strategies have become a lot more defensive... Basically this means that we've stopped trusting that projector manufacturers will build projectors that are 1000000000% robust... For that reason what you experienced would not have been possible with QuickShow or BEYOND, even having a projector with drive electronics that were not functioning correctly. Nevertheless, our position is that YOU have done northing wrong. It is the equipment which let you down... (Again -- hard drives never catch fire, regardless of what whacky things computer users do...)

I think the best solution to the problem that you have experienced, and more, would be to engage in a training session to learn how to use the software better. Such training would allow you to more fully understand the limitations of laser projectors and of the software, as well as giving you a good background on making laser shows. We tend to offer public training sessions once per year (usually taking place near tradeshows) and also arrange private trainings at our office from time to time.

Best regards,

William Benner