current over

[bbrreid]

Hi everyone
I have a Shibaura VMC-4 (made by Toshiba circa 1981) machining center with
a Tosnuc 520M control. we had a problem with the spindle drive and replaced
the 12 transistors (2sd646a) and with the machine being powered down for months we had to reinstall the parameters.it worked ok for a few days apart from the spindle struggling to start, but now we have an error message of "current over" code 8-11 and a red light on the spindle drive board.could it be that we made a mistake with the parameters?
can anyone help? or put me in touch with someone who has worked on these machines
thanks
brian

[H500]

I don't know anything about the machine, but I'm guessing that that the message means "overcurrent". Since it's Japanese, the messages can be funny sometimes. Did you set the current too high somewhere?

[bbrreid]

Hi,
no we didnt change any settings.
can the machine parameters change this?
we have 2 books of parameters and some have been scored out and changed by the previous owner

[Al_The_Man]

Which transistors did you change? In some cases the drivers get taken out when the switching modules are replaced, and vice versa. In most cases the manufacture recommend replacing the drive board when the switchers are replaced, otherwise you end up with the same problem, i.e. overcurrent.
Al.

[bbrreid]

Hi Al,
I will have to check with my son (he did the repair and is on vacation).
he changed the large transistors (2sd646a which has a built in diode) because they had a hole blown in the side wall. he also found a loose earth cable behind the drive and thinks this may have caused the blown transistors.
he also replaced all the cooling fans. must have another look at the drive board because we have a red led lighting up
thanks
Brian