Re: [CAD_CAM_EDM_DRO] what will i damage?..running 220 1ph into220 3phase transformer?

Mike Mueller wrote:

>Bridgeport Series 1 w/Boss 3 controller:
>
>looking at the main electrical box, I wired up power going to only 2 of the 3 main fuses as follows:
>(left to right)
>
>left= hot
>middle= hot
>right= no connection or power
>(yes, machine is grounded)
>
>The three transformers for the steppers read 53vdc, i can feel that the stepper motors get energized. The controller does not work, which is fine since it's being removed as the Bridgeport will be operated via my PC and G201's.
>
>Am I asking for trouble running it this way?
>VFD is going to run the spindle motor.
>
>

There are some things you need to understand about the BOSS.
The transformer and rectifier will not be sharing the load between all 3
phases. I think the transformer has a 230 V tap, you should use that, and
not the 208 V tap, if any. You don't want to overexcite the transformer, or
it will draw excess current and run very hot. The capacitor will have more
voltage ripple than it would on 3 phase power, but this might be acceptable.
Use the AC range on a DVM and see what it reads (under load).

Since you will be using Gecko drivers, you don't have to worry about the
saturable reactor that Bridgeport used to control motor current, the Gecko
will do a better job of that.

If nothing gets hot, and the AC reading on the cap is only a couple of
Volts,
then you should be fine. If the AC reading under load, like with the motors
moving, is over 10 volts, then you definitely need to increase the capacitor
size, or just replace it, it may be wearing out.

Jon