The Craftmans Shop > New from Old
The Sequel - Oh Blimey I bought a CNC Lathe (Beaver TC 20)
awemawson:
Well chaps what I SHOULD have done is disconnect the three wires and test it 'in situ' using my Proximity Sensor Tester, that I had completely forgotten that I had until a lull in the music this afternoon :bang:
Would have saved so much time. When I put it back, even though it is obviously not in use, I'll use the tester to set it up so it can work should the need arise.
The wire connected to the output is held firmly at a nominal 24 volts DC - so no way the sensor will have any affect !
It's detecting (in the original concept I think) a notch in a very slow moving disk of steel, so I'd guess it's a simple induced magnetic one, but it bears no markings.
awemawson:
--- Quote from: vtsteam on July 22, 2018, 10:01:53 AM ---
--- Quote from: awemawson on July 22, 2018, 07:21:38 AM ---....
Permanent 24 volts - nothing detected. Just to be sure, I took the cover off the terminal box mounted on the turret, checked that the sensor had it's 0v and 24v supplies, and it's output was permanent 24 v. OK faulty sensor - unscrew it. ....
--- End quote ---
Isn't that inverted compared to your test?
--- End quote ---
i was turning the turret back and forth across the notch where we should go from detected to nothing and back to detected. In practise of course nothing was detected as the sensor output was nobbled !
awemawson:
:thumbup: :thumbup: Well developments :thumbup: :thumbup:
I put the Index proximity sensor back. In order to start the thread on the device I had to unsheathe the other sensors to get the alignment right. Then I set it up using the little test box, and then got to wondering about the odd wiring. A multi-core cable takes the four outputs from the Euchner Tool Position Sensor directly to digital inputs. But it also provides 0 volts and 24 volts to the sensor and carries the Index transducer output to Terminal 100 on the Violet wire. Then from this terminal a green wire goes back to the SMCC card to it's Index input. Now this is illogical, as Terminal 100 is permanently at 24 volts when the system is 'up' due to the CR10 / CR20 'Volts Healthy' relays.
I reasoned that this is a cock up, and that the Violet Index output and the Green Index Input should have been joined using the adjacent terminal 99 so that a genuine Index signal is provided at one point in the rotation of the Turret Tool Disk due to the notch in the clutch disk in it's innards.
. . .so take your life in your hands and alter the wiring . . stop fussing :ddb:
Well I did, and do you know - since then the Turret has performed faultlessly :clap: :clap:
Now actually this is very odd, as that Index signal is usually at 24 volts, and when the Turret is initialised it doesn't rotate the tool disk so the Index signal will remain at 24 volts just as it would when it was connected to Terminal 100 :scratch:
But let's not get carried away, it works. It just might be with all the dismantling and reassembly I have made good a poor connection, but, fingers crossed, the Turret does what it is supposed to do :thumbup:
On the Spindle Motor Field Coil driver front, my chap has gone very quiet and is not answering texts or phone messages. I've actually ordered all the semiconductors on the board as a fall back solution, but would far rather have a known good service spare as had been offered. We'll see which arrives first. Certainly the component approach would be far less costly.
awemawson:
So to celebrate I at last got round to changing the hydraulic solenoid 'Tell Tales' - originally there was a DIN 43650 socket fitted to each hydraulic solenoid valve, with a 24 volt 'Pea Bulb' to indicate the state of the valve.
Most of the pea bulbs had failed, and their heat had made the plastic of the sockets very fragile - I'd not been able to source replacement bulbs of a low enough wattage, and it turned out that the complete modern version with a red LED instead of a bulb was not much more than the non existent bulbs anyway.
There are ten hydraulic solenoid valves on this machine - handy as the tell tales come in five packs! So this afternoon I've installed the first five in the tail stock hydraulic cupboard.
Should make fault finding a bit easier - still five to go in the chuck control cupboard.
Pete.:
We have those on some of the demo robots at work. They ain't half handy when something doesn't move when you tell it to, cuts down the diagnostic time drastically.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version