Alln1DC Bridgeport series 2 interact 2

[centroid467]

CAPBRDHI uses a single diode for rectifying each side of the split secondary. If the output voltage across the 180 taps is 124V then the effective VAC going to each rectifier from the 180 to 0 taps is half that. Peak voltage at 124Vrms is 175.4 V and you'll have a peak of 87.7 V less the diode drop coming out of the rectifier for the output.




For Marc's suggested wiring with CAPBRDHI and 220-240 Vrms service going to the 460V and 0V primary taps then CAPBRDHI connected to the 180 taps, you would end up with 90 Vrms between the 180 and 0 taps. This 90Vrms gives peak voltage of 90 * sqrt(2) = 127.3 V. This is much closer to the servo max ratings and would give better performance.


If I misunderstood what you have wired, please correct me. What mains service voltage do you have available? If you only have 120V available, I would not recommend using this transformer to power the servos. Feeding 120V into the 210 or 220 primary taps gives a rectifier output voltage just above 140V. This would work but exceeds the voltage rating of the motors. The other taps give rectifier output voltages below 90V.

[Snap-On Phil]

I’ll see if I can get the 180 ish voltage out of the transformer where it’s marked “180 “ and see if “0” is 90v. I guess I achieve this by placing my 2-120 legs on random other lines on transformer. If I place incoming 1st leg on 180 and other leg on 180 then I have 240 in and 124v out across 180. Or am I supposed to wire it with only 1 leg of 120v ?

[centroid467]

I don't think any of that will do what you need.

Your best bet with 120Vrms service is to get a step down transformer that will take it from 120 to 83 such as our transformer Part #1171 or similar then use CAPBRDLO.

See here for schematics of that with a CAPBRDLO: https://shopcentroidcnc.com/shop/cnc-ac ... generator/

[Snap-On Phil]

I have 220 service....2 120vac lines. going into transformer on 180 and 310 giving me 159.8vac on lines 180 and 180, when I put the negative side of CAPBRDHI to 0 on transformer I get 109vDC out of CAPBRDHI, that just seems low if the servos say 140v. so how much lower than stated voltage on servos is, ok? is there any benefits to higher voltage say 130vdc as compared to 110vdc

and I now have both a CAPBRDLO and CAPBRDHI and I can achieve 83v without more equipment.

[centroid467]

The main effect of a lower voltage on a permanent magnet DC motor that we are interested in is lower max speed. Your SEM MT30Z4-61 motors will reach the rated max speed (2300 RPM) at 140VDC. At 130VDC, they will go to (130 / 61) * 1000 = 2130 RPM. At 110 VDC that goes down to (110 / 61) * 1000 = 1800 RPM.


I'm not sure what to make of that wiring. Would you mind posting pictures?

[Snap-On Phil]

Sure I have one I just took.
Temporary wiring till I have it sorted out. The red wire is going to the negative of the CAPBRDHI.

So 1800 rpm ok ? I’m assuming I’m not using rapids that often.

[cncsnw]

That is very odd.

You imply you have connected a CAPBRDHI, but your picture only appears to show four wires connected to the transformer.

Given that the CAPBRDHI requires three wires (one from the center tap to minus, and two to the stud diodes), how are you feeding AC into the transformer?

[Snap-On Phil]

look closely at tap 180 there is 2 wires on it,

[Snap-On Phil]

Well I passed my system test today. And it’s all working nicely.

Now what I’m not sure on is my Vfd. It’s a Durapause gx10. It’s not turning spindle on when I touch the panel for Allin1dc control ,but i can hit the on button on the Vfd and motor starts. I can see on the Allin1dc screen that it sees when I raise or lower the rpm by the keyboard, and I hit the green button and the start button no motor. I’m assuming it’s the settings on the Vfd. Any help from anybody

[cncsnw]

Supposing you meant "Durapulse GS10", then the manual is here:
https://cdn.automationdirect.com/static ... manual.pdf

You probably need to review your settings in P00.20 and P00.21.