Okuma LB 12 CNC Lathe

[rajappa]

I have a Okuma LB 12 CNC Lathe with OSP 500L-G Control. The spindle is not working and it gives an error 110 Alarm A - SDU. Can anybody give some details on this problem

[broby]

This error is indicating that there is a problem with the spindle drive unit.
This is NOT GOOD!
Every time something like this happens it has always ended up costing a fair bit in repairs. Unless you have a good service tech on hand you will need to contact Okuma Service for help.
Brian.

[rajappa]

broby. Thanks for your post. From spindle drive LED indications, it shows power transisters short. I am yet to dismantle the drive unit. Are these transisters available in the electronic parts shops ? The spindle drive model is VAC Type A.

[chango]

rajappa

about your question, on the transistors, let me tell you that those are kind special, originally from Fuji with a propietary OKUMA specs, but time has past that i guess you can find a substitute. so just google the number printed on a the label in one of the sides of the module.

but the alarm 110 also can be caused from the regenerating resistors.

I really suggest you to measure the price of these components, versus a new VFD from another vendor.

I did some drive retrofits to an older OSP 500, and OSP5020 with minor modifications to the schematic. using Mitsubishi drives.

call any VFD service center in your area, they i mean the service people normally just need the machines electrical schematic.

(note not all the OSPs can be retrofited) but you are lucky because the LB12 were not made in America and the Japanese versions are more easy to Hack

regards