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View Full Version : Help with turret encoder of Baruffaldi Turret TOE100 to retrofit old CNC



Jerico
22-09-2022, 05:41 AM
Hi!

I'm new so I hope I did post this thread to the right category.

We have a very old CNC that hasn't been used in like 20 or more years and since I just graduated, I was tasked to retrofit it. Along with this is the Baruffaldi Tool Turret - TOE100. The thing is, I was told to control the turret using a PLC (FX3U clone to be exact). I refer to this manual: 31251. Firstly, I need to test out the positions of the tool turret.

The Encoder Code Table shows this:
31252

I may be wrong but through very limited research (due to lack of information in the net), I wired the encoder to the PLC like this (NOTE 1: Supply Voltage = 24VDC) (NOTE 2: FX3U and the encoder are connected in parallel to a power source through DC+/DC-):
31253

And programmed it like this:
31254

The problem is, when I test it, it does nothing. The contacts do not close in accordance with the should-be position of the encoder. Can it be that the encoder is faulty? If my wiring is wrong, can you guys help me?

If you need more info, please don't hesitate to ask me.

Thank you so much!


Regards,

Jerico

Voicecoil
22-09-2022, 05:23 PM
Are you manually rotating the turret to check the encoder outputs? That would be my first step. And I wonder whether the COM pin on the FX3U needs connecting to 0V perhaps?

m_c
22-09-2022, 08:14 PM
Are you manually rotating the turret to check the encoder outputs? That would be my first step. And I wonder whether the COM pin on the FX3U needs connecting to 0V perhaps?

Most likely this.

Easy way to test the encoder outputs, is with a multimeter. If you're getting voltage, then the encoder is at least doing something.

BTW, you probably don't want Strobe being used as part of the position calculation.
Strobe is used as part of the locking process and triggers the locking solenoid timing.
To calculate position, all you need are the Bits (A, B, C and D). You don't even need to use Parity, as it's sole purpose is to provide a basic value check.

I still have the PLC code to control a TOE80 using a Click PLC, but I no longer have the software installed to view it.

Jerico
23-09-2022, 02:43 AM
Are you manually rotating the turret to check the encoder outputs? That would be my first step. And I wonder whether the COM pin on the FX3U needs connecting to 0V perhaps?

Pardon me because forgot to mention that I did try connecting COM to DC- but it does not work. I also did try connecting the blue wire to COM. Nothing changes - the PLC contacts do not respond accordingly.

Jerico
23-09-2022, 03:04 AM
Most likely this.

Easy way to test the encoder outputs, is with a multimeter. If you're getting voltage, then the encoder is at least doing something.

BTW, you probably don't want Strobe being used as part of the position calculation.
Strobe is used as part of the locking process and triggers the locking solenoid timing.
To calculate position, all you need are the Bits (A, B, C and D). You don't even need to use Parity, as it's sole purpose is to provide a basic value check.

I still have the PLC code to control a TOE80 using a Click PLC, but I no longer have the software installed to view it.

I'll try to test it. If it does not provide voltage, can I conclude that the encoder is faulty and needs replacement?

In regards to Strobe and Parity, If I understand correctly, I should remove Strobe and Parity to the position calculation (the PLC program I showed) right? Then, I will use Strobe for another rung for the locking process. Right? And I should completely remove Parity from the PLC program and disconnect Parity from wiring?

Too bad to hear about the PLC program of Click PLC. That would be a great resource to have in the next steps.

Doddy
23-09-2022, 08:02 AM
I may have repaired a similar encoder (at least I recognise the name of the turret) before now for another forum guest. Anyway, the first thing I'd look at is if there's a pull-up on the inputs to the PLC. Gimme a sec, let's see if I have some old photos...

3127331274...

If your encoder looks like one of these - essentially, unless there's a common-mode failure (e.g. supply line to the PCB) then each of the 6 signals is independent from the other - and it's highly improbable that the entire encoder has failed. I'd have to really dig around for any notes I may have but believe the encoder outputs are open-collector. If the PLC doesn't provide a pull-up, or cannot be configured to switch-in a pull-up then try with a 1k-10k resistor between DC+ and the output.

For information - the failure mode experienced by this encoder - twice over two years - was the failure of the photo-diode on the encoder board. Last pass I replaced all diodes.

Muzzer
23-09-2022, 07:32 PM
I've not used it myself but the Click plc editor seems to be free to download and use. If m_c still has the code, you should be able to open and play with it.
https://accautomation.ca/click-plc-installing-the-software/

m_c
23-09-2022, 09:49 PM
I'll try to test it. If it does not provide voltage, can I conclude that the encoder is faulty and needs replacement?

In regards to Strobe and Parity, If I understand correctly, I should remove Strobe and Parity to the position calculation (the PLC program I showed) right? Then, I will use Strobe for another rung for the locking process. Right? And I should completely remove Parity from the PLC program and disconnect Parity from wiring?

Too bad to hear about the PLC program of Click PLC. That would be a great resource to have in the next steps.

You can still use Parity for position calculation, as it does provide an extra check that the encoder is on a valid position, but Strobe is only needed for timing purposes.

As per Muzzer's post, I should have been a bit clearer. The Click PLC software is free, it's just that I no longer own any Click PLCs, so have no need to have the software installed.
If you're willing to install the software, I can send you the code so you can load and view how I controlled my TOE 80 turret.

Jerico
24-09-2022, 02:35 PM
I may have repaired a similar encoder (at least I recognise the name of the turret) before now for another forum guest. Anyway, the first thing I'd look at is if there's a pull-up on the inputs to the PLC. Gimme a sec, let's see if I have some old photos...

3127331274...

If your encoder looks like one of these - essentially, unless there's a common-mode failure (e.g. supply line to the PCB) then each of the 6 signals is independent from the other - and it's highly improbable that the entire encoder has failed. I'd have to really dig around for any notes I may have but believe the encoder outputs are open-collector. If the PLC doesn't provide a pull-up, or cannot be configured to switch-in a pull-up then try with a 1k-10k resistor between DC+ and the output.

For information - the failure mode experienced by this encoder - twice over two years - was the failure of the photo-diode on the encoder board. Last pass I replaced all diodes.

I don't think my encoder looks like that. The encoder looks like this.

31278

However, I'll consider what you've said. Thank you!

Edit: If you're pertaining to opening the inside of the encoder, I might check it later.

Jerico
24-09-2022, 02:47 PM
I've not used it myself but the Click plc editor seems to be free to download and use. If m_c still has the code, you should be able to open and play with it.
https://accautomation.ca/click-plc-installing-the-software/


You can still use Parity for position calculation, as it does provide an extra check that the encoder is on a valid position, but Strobe is only needed for timing purposes.

As per Muzzer's post, I should have been a bit clearer. The Click PLC software is free, it's just that I no longer own any Click PLCs, so have no need to have the software installed.
If you're willing to install the software, I can send you the code so you can load and view how I controlled my TOE 80 turret.

I understand the Parity and Strobe thingy. Thank you for explaining it to me clearly. Update about the encoder, I tested it and no voltage was recorded. Seems like the encoder is replaceable...

About the PLC program, I am aware of Click PLCs and I'm willing to install Click PLC software just for the sake of having a great resource and knowledge later on. Thank you so much in advance!

Doddy
24-09-2022, 06:07 PM
I don't think my encoder looks like that. The encoder looks like this.

31278

However, I'll consider what you've said. Thank you!

Edit: If you're pertaining to opening the inside of the encoder, I might check it later.

Actually - that's very interesting - that looks very much like the common-or-garden quadrature encoder - can you post details of the label? (I've tried magnifying and angling the laptop, but can't see enough detail). But I might be heading down a rabbit-hole here. But a quick image of the label....

Edit: Still think testing pull ups is a quick and easy test.

Jerico
25-09-2022, 05:56 AM
Actually - that's very interesting - that looks very much like the common-or-garden quadrature encoder - can you post details of the label? (I've tried magnifying and angling the laptop, but can't see enough detail). But I might be heading down a rabbit-hole here. But a quick image of the label....

Edit: Still think testing pull ups is a quick and easy test.

The thing is the photo I used is just a generic photo of what mine looked like. Since the CNC and the tool turret with it are around 20+ years old, someone might have removed the label. Some things are for sure: (1) It is an 8-Position Absolute Encoder; (2) It looks like the photo I attached; (3) I think it is the original encoder from the Baruffaldi TOE-100 Turret (since the wire colors and how it is assembled to the turret fits the TOE-100 manual).

I'll drop an update after testing pull-ups. Thanks for that.

Muzzer
25-09-2022, 04:22 PM
The position switch on the hydraulic turret on my Tree lathe looks like this visually but it's actually an "8 position rotary switch" by Sanyo. I'm pretty sure mine actually has 8 reed switches in it, as it beeps out in either direction with a DVM. The giveaway is that it has 9 wires.