[Antonio Arguijo]

Hello,
I need a serious problem in several OKUMA machines, LU300, LB300 & LB35, several months ago the inverter units fails, the alarms that appears are:

AL-09

The manual says the we must "change THE WINDING CHANGEOVER MAGNET SWITCH"

Someones knows what is it or where is this switch????

[Algirdas]

Could be factory's main power supply cable phase change issue, if several machines has the same trouble at the same time.

[Antonio Arguijo]

Algirdas, Good day!!!
Exists a confussion, because suddenly the alarm appears on the displays drives the alarm EL-09 or EH-09 (doubles), but sometimes appears AL or AH-09. Also the alarm EL or EH-11 appears, both alarms refers to encoder voltage and control. What do you think it's the problem?
Because we send to repair the MIV units, but when we change them, only works 3 or 4 weeks, and the alarms appears again...also in new units MIV....

[underthetire]

the first alarm indicates the spindle high/low contactor is either not switching, or not seeing the switching (aux contacts). Some machines had a small board next to the contactors for the switching functions.

[Algirdas]

only works 3 or 4 weeks, and the alarms appears again
check if You can install main power supply monitor. Something common must be with these machines: maybe power supply is faulty.