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converting galvos and pin assignments

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Hello, I just got a new used pair of galvos. They are GSI Lumonics g325D.
I would like to install them into a case. I have a showcard with a lot of patterns I really like, but the old galvos they went to have a vastly different pin layout.


The new galvos have this layout assignment on there with part of its connector


The old galvos use this connector here

Can I make this work with the showcard I have? Its clear there are less pins.
 
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diachi

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Need more details and more pictures of the components. Just now I have no idea what's what.

What's in the picture you posted? Is that the old galvos? New Galvos? Is the show card pictured? What model are the old galvos/show cards? Was it just a MIDI show card with a bunch of stuff pre-loaded onto it or was it a show card that could take an SD card or some such with .ILDA files on it?
 

Benm

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Which one is the problem? The one with the 16 pins on it seems to have a pretty good description of the pin functions right on the pcb.

The ones with 6 pins for each axis could also be quite standard, but they are just the galvo mechanism and require the appropriate driver board to operate. These pins generally just carry drive current and some feedback information, but without the matching driver they could be hard to get to work.
 
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That is the showcard. The thing that doesn't have an assignment layout is the other set of galvos that came with the showcard, but I am pretty sure this description here is from the same galvos I found on ebay. My biggest concern is that I don't want to burn out the galvos, but if most of the pins are simply unused then I feel it would be worth it to make it work or at least try to make it work and see if I can get results.
If they definitely won't work, then which showcard can I buy that will work with my galvos?Could I possibly program something to remux those signals to translate properly like in some sort of flash chip or something?

 
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I just noticed that there are actually two inputs. X1 and X2. The connector diagram was for the x2.
This is the x1
It seems like a lot of these pins have several things going to the same pins so it only has a total of 6 controls
The controls reads
1/2/3 XH
4/5/6 XL
7/12V Sen X
8 sig GND X
9 sense +x
10 sense-x

Does that seem a bit more manageable to switch now? The voltages are different, but I know how to step down voltage if I need to. The showcard has ilda and I am assuming it will be somewhat possible to adjust the galvos somewhat inside the software right?

 
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Each different configuration of number of assignments pins and inputs/outputs required different test fixtures
 

LSRFAQ

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G325 use a RF driven capacitive position sensor that outputs a few microamps per degree of current riding on a 2 Mhz broad spectrum RF hash that has to run through a low pass filter and into a current to voltage converter based on a differential amplifier.

The more modern galvos output two very weak voltages from two or more photocells that look at light passing through a mask or off a mirror on the shaft. This is known as optical position sensing.

Your trying to hook Apple's to Oranges.

You need either a GSI/lumonics amp or a Cambridge style optical amp, but they are not interchangeable without building rather complicated adapter cards.

I'm skipping details on oscillator supply voltages, automatic gain control feedback, led current needed, and how the galvo coil wiring needs to be separate from the feedback wiring.

G325 has a massive shaft with a lot of inertia, and g325 amps have a few different parts installed vs g120 amps in order to optimize the frequency response.

I rarely come to this forum, start a post over on Photon-lexicon and I'll try to help you.

Btw, the g325 are a factor of four slower then the old galvos, making this all a moot point. You could fix some old 660 series amps from EBay to drive the G325, but I'm not so sure why you want to do that.


Steve
 
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All different conformation of quantity of assignments pins and inputs/outputs required special scan fixed object.
 

paul1598419

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All different conformation of quantity of assignments pins and inputs/outputs required special scan fixed object.
This is an old thread and this is your first post. It is considered bad manners to post to old threads here. You should open an introduction thread and tell us a little about yourself.
 




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