I have questions on the Bridgeport DC power supply for someone. I'm thinking the steppers need around 55 DC volts. Is this correct.

Next, where do I find this DC voltage on the Bridgeport power supply. I find 6, 9 and 24 DC volts. 56 DC volts on wire #75 but I can't see one wire running 3 steppers. I would like to use the power supply Bridgeport built if I can find the right voltage.

I have read where guys built their own power supply using the existing components. Under the 3 phase transformer are the "saturable reactors". I found some wires marked + and - minus on the 3 reators that each show 38 AC volts. I'm thinking a bridge rectifier connected connect there would give me around 50 DC volts but have yet to try it without asking around first.

So my question is this. What DC voltage should I be looking for to run the steppers? Does the Bridgeport power supply have that voltage? If not should I make a DC power supply using the 38 AC volts available at the saturable reactors?

Once this DC power is resolved I'll be able to finish this thing up in a few hours.

Thanks
Jim

I believe that at fuses 12, 13, and 14 you will find about 56 VDC. These are the fuse protecting the output to the stepping motors. Fuses 15, 16 and 17 are the AC side of the axis drives. Both sets being X, Y and Z axis.
The saturable core reactors are to limit the current using the ACC board. The bridge rectifiers are mounted on the back of the large bank of capacitors just below the tape reader.

George

Transformer T6 is the 56V transformer (paralleled secondarys 40Vac). Wire 75 is the 56Vdc output from the bridge rectifier BR1 and it feeds fuse FU10 (3-2/10A). FU10 feeds wire 74 with 56Vdc which connects to the three reactors SX1, 2, 3. I don't know what the KVA rating of T6 is, but a 3-2/10A fuse can't be enough to run 3 stepper drives at the same time.

That 56 V supply is used by the ACC board to regulate the current through the saturable core reactors.
Fuses 12, 13, and 14 each supply 8 amps to each axis from bridges 3, 4, and 5 per the schematic, wires 24, 26, 28.
The AC to these bridges comes from transformer T2, through the saturable core reactors which is how the current is regulated.
A circuit diagram is in the maintenance manual.
I will try and attach that page.
In a prior trend, I had attached a description of the entire design of the drives.

George