Okuma LC-20 Threading problem

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Metlmunchr:
just a thought, back emf from dynamic brakes was sometimes used (TRAUB TNS-42) through two systems instead of the good way of just dumping it through a stove element on top of the machine (HAAS VMC). The first system used a phase converter to run a refrigerant pump to cool the power cabinet! The second actually dumped it back into the three phase transformer! Ours eventually made 700 volt arcs back through the chassis of the cnc lathe and zapped our Chinese machine operator in the bare foot as he was monkeying with the door switch on top. He never said anything for years but he should have. If I had one I'd definitely get your tech to rewire the back emf system through a stove element and put a fan in the back cabinett.

gmsmachinists: my early 80's OKUMA LB-15 had a two hard drive computer, you had to enter bb1*.* to get the program list for the Back Buffer number one. There is also another secret one, bb0*.* which gives a bunch more programs. These old systems are so slow I would DOWNLOAD and dump every PART program in the machine's buffers but make sure you download them into a laptop and make a floppy disc for them! Having less data in there should make the machine feed hold a lot faster, maybe save your life too. Ask your tech to download all the parameters into your laptop for saftey, there are binary numbers for registers that only the assembly team that put that particular machine together knew at the time, so they can be hard to get if the system or the cpu fails and mixes up the parameter memory registers.

[Rafafa]

Dear CNCZONERS...As a new kid in this town, i would like to leave my greetings for all of you, hoping that i can learn a little bit about CNC´s.
I am an 28 year old electronic engineer, and i do not know much, about CNC´s. But last week, i was called from a automotive parts factory, that has many CNC´s (ROMI, MONDIALE,Etc), but has also, one particullary special CNC, a OKUMA LC20 retrofitted by a SIEMENS SINUMERIK 820D. The owner of this factory, bought this CNC as a working one. The thing is that, this machine has never worked, since the retrofitting was made.
When the machines came, everything seemed to work well. The axes could be referenced. But, it was impossible to run a program. After some tries, with some mysterious technical support man, that have never found the problem, because he actually didn´t know anything about the machine, they left the CNC to RIP.
The first time, i visited this factory, i turned on the CNC and after clearing the 25050 error, the ZA, ZB and XA, XB axes started to displace around 3 mm per minute; even with the displacement knob at 0 position.
After that, i took away the 4 circuit boards of the axes and i made a revision, replacing all the electrolytic capacitors. The mayority, were dry and some others were leaked.
The problems subsists. i have now the two Z axes blocked (the two turrets have achieved the positive Z limits) with an error shown by a red led on the circuit boards. Also i do not know how to reset that errors, on the boards.
Sorry if i make you suffer from bordom all this time, but i need some help and as i have already say above, i do not know much about CNC.
May be there is (i almost sure that it is) way to reset the whole Sinumerik interface, to start from zero, in order to re-program all the parameters.
Thank you, all of you!! Best regards!