Brad93
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Agroshield
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I think something like this would be a close relative of the part spanning the slotted disk:
See if it has a part number or manufacturer on it and you will find a datasheet telling you what its output should look like.
The wiring is bottom right of diagram on p.44 of manual above.
It should be simple to verify that one: give it power and when the light beam is through a hole, it will register an output. When the beam is blocked, it won't.
To make that work exactly as is, you'd need a tacho that has a configurable number of pulses per revolution. A lot of the cheap ones only work on single ppr and that makes the display a bit vague at slow speeds because it is a long time (in computer terms) between seeing pulses
At very worst, you might have to make up another holey disk with fewer holes in it.
See if it has a part number or manufacturer on it and you will find a datasheet telling you what its output should look like.
The wiring is bottom right of diagram on p.44 of manual above.
It should be simple to verify that one: give it power and when the light beam is through a hole, it will register an output. When the beam is blocked, it won't.
To make that work exactly as is, you'd need a tacho that has a configurable number of pulses per revolution. A lot of the cheap ones only work on single ppr and that makes the display a bit vague at slow speeds because it is a long time (in computer terms) between seeing pulses
At very worst, you might have to make up another holey disk with fewer holes in it.
It's not a complicated PCB.
I can't quite make out the numbers, but the on the front photo you posted, I'd say the top right is the voltage regulator.
It's a Siemens L something. It looks likes L9245H, but that doesn't bring up any data sheets, and I suspect the 4 isn't a 4. If you can find the datasheet for that, you should be able to trace what is the input power, and what power it's outputting.
The opto will likely need DC voltage, so if you can figure what pins are outputting DC voltage, combined with where the 24VAC is coming in, that should only leave figuring out what
I'd guess the big resistor on the back is a crude voltage dropper pre-regulator IC, and the diode on the right hand side is being used as a half wave rectifier to get DC.
It's a Microchip PIC doing the processing on the top left, and I'd guess the lower left chip is most likely a register shifting IC for driving the LCD.
However, having a look at the wiring diagrams.
Starting at the left (the labelling isn't very clear, so I'll simply start at the left)
1 & 2 - Power in. Going by the notes, this should be 24VAC. Going by the fact the second wire is labelled F1, I'm going to assume that means Fuse 1, so i'd guess F1 should be the 24VAC, and 2 0V.
3 - Red to sensor (assuming conventional wiring, I'd assume this is going to be 5VDC or 24 VDC)
4 - Green from sensor
5 - White from sensor
6 - Black to sensor (0V for sensor power)
7 - CN15, wire 60, which appears to go here, but I can't fully make out the writing -
And also having checked the 24VAC supply on that same diagram, my assumption above appears to be correct-
I can't quite make out the numbers, but the on the front photo you posted, I'd say the top right is the voltage regulator.
It's a Siemens L something. It looks likes L9245H, but that doesn't bring up any data sheets, and I suspect the 4 isn't a 4. If you can find the datasheet for that, you should be able to trace what is the input power, and what power it's outputting.
The opto will likely need DC voltage, so if you can figure what pins are outputting DC voltage, combined with where the 24VAC is coming in, that should only leave figuring out what
I'd guess the big resistor on the back is a crude voltage dropper pre-regulator IC, and the diode on the right hand side is being used as a half wave rectifier to get DC.
It's a Microchip PIC doing the processing on the top left, and I'd guess the lower left chip is most likely a register shifting IC for driving the LCD.
However, having a look at the wiring diagrams.
Starting at the left (the labelling isn't very clear, so I'll simply start at the left)
1 & 2 - Power in. Going by the notes, this should be 24VAC. Going by the fact the second wire is labelled F1, I'm going to assume that means Fuse 1, so i'd guess F1 should be the 24VAC, and 2 0V.
3 - Red to sensor (assuming conventional wiring, I'd assume this is going to be 5VDC or 24 VDC)
4 - Green from sensor
5 - White from sensor
6 - Black to sensor (0V for sensor power)
7 - CN15, wire 60, which appears to go here, but I can't fully make out the writing -
And also having checked the 24VAC supply on that same diagram, my assumption above appears to be correct-
The top right is an opto-isolator, which I'm guessing is providing some input protection from the opto-sensor, in case something goes wrong.
And the top left is a what you've just posted (I mistook the Motorola logo for Microchip), and uses the AC input as a time clock to generate a comparison with the opto sensor.
The lower left chip might be a micro-controller, and may explain why it's been defaced.
I'd start with the basics, like making sure you're getting 24VAC.
However I'm wondering about that other wire, that we can't make out the writing for. Should the tacho be permanently on with the lathe on, or does that extra wire switch the tacho on?
And the top left is a what you've just posted (I mistook the Motorola logo for Microchip), and uses the AC input as a time clock to generate a comparison with the opto sensor.
The lower left chip might be a micro-controller, and may explain why it's been defaced.
I'd start with the basics, like making sure you're getting 24VAC.
However I'm wondering about that other wire, that we can't make out the writing for. Should the tacho be permanently on with the lathe on, or does that extra wire switch the tacho on?
sako243
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Can you get a part number off the photo sensor? Or some better photos of it.
I'm away currently for a work trip tomorrow and then some deer stalking but once I'm back / in the lab next week I can knock you up a circuit board with display to do what you want.
To make this easy at my end and yours all I'd need is:
1. Ideally a part number or pin out for the photodiode (we could work it out if need be).
2. Confirmation you have a 24VAC / 750mA supply to the display box
3. Number of holes in the disc
4. Ratio of spindle rpm to disc rpm
If you want it made to suit the same holder / box some dimensions of the display would be ideal.
Brad93
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Blimey Sako that's a blinding offer.
I couldn't see any markings on the sensor, however i've not yet been in touch with 600 group to see if they have any other schematics. They may well come back with a drawing or part number.
I will remove the sensor and have a good look at it in the meantime.
I'm not using the lathe currently, so what i can do is take the sensor and pcb/display off completely, and send that up to you when you have a spare moment?
Yes have 24v up at the board.
Disc is mounted directly to the end of the spindle so ratio would be 1:1?
Will count holes in the disc when i'm next at the workshop.
