basic 3-phase xfmr power supply questions. re:7i29

If You do not need independent powersupplies I would recomend sticking with six phase star connection.

A suitable diode connection as shown iin concjunction with single DC output and a common star point is a great LOW STORED ENERGY solution while maintaining a very low ripple .

Six phase combo will result in twelve pulse rectifier output giving under 3% ripple with no filter capacitor.
No filter cap no energy to be dumped anywhere under emergency conditions.

Zig wrote:

Six phase combo will result in twelve pulse rectifier output giving under 3% ripple with no filter capacitor.

As Peter pointed out, it is the only topology suitable for the required voltage.

No filter cap no energy to be dumped anywhere under emergency conditions.

Interesting point!

I am under the impression that for the 7129 H-Bridges the capacitance is required to protect against surges. From the 7i29 manual:

The 7I29 does not have any braking or load dump capability, so if the 7I29 is operated near the maximum power supply voltage, either sufficient external capacitance or and external voltage sensing brake circuit may be required to prevent excessive voltage surges on the
motor power supply when decelerating large motors.

And from post 13275@ SETUP OF MESA 5I20/7I29 FOR DC SERVO MOTORS

Yes you need a large electrolytic capacitor on the output of the rectifier to absorb reverse energy from the motor inductance(s) Probably on the order of 10000 uF. Its not safe to run without this capacitor

So thats a conumdrum.

I should note that the existing e-stop circuit de-engerizes a NO relay at the input of the servo power supply xfmr. Relay C1 at 2-3.
Sixis S2103 Circuit .