Mirac Turret info needed.

[john11668]

Hi folks and thanks for having me .
I have had a Denford Mirac for some time and am slowly but progressively trying to make it work.
The previous owner said it had been working but "it just stopped loading G code". From what I have seen I am now taking this with a massive pinch of salt but I am not unhappy as for the price it is still good value to me .

It has a six station RH80 turret toolchanger , and I have all the manuals for the machine .
I has a Keb inverter and two contactors which select spindle motor or turret motor, which I understand is a later control system. But I am struggling to understand features of the supply .
It would seem that the inverter gives a 230v 3 ph supply to either the spindle or the toolchanger ( clearly not simultaneously) yet the Baruffaldi RH80 has a label which states 110v and this is my puzzle. There is no evidence that this is not the original unit, and the schematics show no transformer in the supply, so in order to plan my project I really need to understand how the supply voltage is changed to be suitable for the Turret motor. Can anyone help with this please .

I do not have a diagram for the tool changer so I also wonder if its motor is wired in delta or star configuration.
Any help would be appreciated
TIA John

[Martin]

I have attached the electrical drawings for the MIrac PC from 1995 showing the shared spindle/toolpost inverter but with the DM8 toolpost.

The RH80 works exactly the same. The inverter is programed to alter the voltage depending on what input is requested.

[john11668]

So does this mean a call for the turret to rotate reduces the voltage to 110, and is the frequency reduced too? With frequency dropped to say 25 hz , then you would expect the voltage to be dropped to around 110 .
Is this part of the process?

[Martin]

Yes.

I think we set the HZ to 37 but not 100% on that. It also controls the accel & decel.