Faulty programmable tow-along tailstock on LB15 with OSP7000

Hi,

We have a 1996 Okuma LB15-IIM with OSP7000 control and programmable tow-along tailstock. The tailstock have been unused for several years, probably even before our ownership. This summer we had the machine thoroughly serviced and got the tailstock back into service, besides a major problem with using it in programs.

The problem is in short that G152 end with error "1261 Tow-along tailstock clamp/unclamp". When issuing, say, G152 w100, in program og in MDI, the saddle connects to the tailstock, tow it into position and backs up to releave pin pressure. When disconnecting the alarm occurs. The manual suggests adjusting LS's.

Manual towing works fine. Returning to connect position, clamping and unclamping works from the buttons on the control panel. M188/M189 also works, as long as the sadle is in the right position (does there exist M-code for returning to the connection position?)

The manual states for error 1261 with no code: "Neither connection ON nor connection OFF signal is output for more then three seconds.". In CHECK DATA all related inputs seems correct.

The control panel buttons shows up in the field net list as expected; TSRE, TSCN, TSUN. Corresponding outputs TSCN and TSUN follows as expected.
Input and output for TSCL and TSUC also shows up as I would expect. (all these are from page 13 and 15 in check data).

I can't find any connection between the 3 seconds mentioned in the manual and what is happening on the machine. Could there be a parameter for this timeout somewhere that have been set to 0?

I would very much like to have the program moving the tailstock into postition than moving it in manual mode for every part. I am turning pipes, and the travel on the center is just a tiny amount to short for chancing parts without moving the whole tailstock ...

I’d go back and concentrate on the TSCL & TSUC signals. I think you may be seeing them at times but they may not be occurring as expected. If the control is not seeing it within 3 seconds, it’s not likely the signal is there. When the alarm occurs does it happen immediately or does it take 3 seconds after the command before it occurs?

There is no m code for positioning it is done with the G152.

Best regards,

The alarm occurs immediately when clamping the tailstock again, and only with G152.

I will check TSCL and TSUC again.

Test to see that if you do the M188/189 that the STM light actually goes out and does not stay lit. If it stays lit, the m code is not being answered.