CNC 11 180 VDC or 90 VDC bus voltage

[kf5pv]

Please forgive my ignorance but I am no kind of machinist.
I have this CNC 11 system with a DC3IOB And a DC1.
my X,Y, and Z, axis motors are 180 VDC.

We have replaced the DC31IOB three times, from what I hear. I am the new guy. but very electrically sound.
Anyway. my first question is if our D.C. bus voltage is around 97 VDC Isn't our current on the drive going to be nearly double since we are at half of the rated voltage? is this Okay?

From what I have read the newer version of drives are capable of 180 VDC bus voltage, if this is correct how do I know if my repaired unit is or is not cpable of the 180 VDC Bus voltage? on the DC3IOB and the DC1?


I have some prints but it shows 120 VAC as the incoming power. we are using 240 VAC 3 phase Hi-leg Δ.

It look like the capacitor in there may be rated at 7000 Mfd 150 WVDC from what I can read. I have not looked at the full-wave rectifier bridge to try to see what the rated voltage is on it.

Is the system engineered as such so it is tolerate to run 180 VDC Motors with these drives with only 97 VDC bus voltage?

Last thing is a axis 4 fault. axis 4 has been removed but I have a com fault for it. also fault 3 on DC1.
I followed the instructions I had to remove the axis in the (config file 311 0.000) but It was already 0.000

Thank You so very much.

[diycncscott]

Hello,

When requesting support, please always email (tech@ajaxcnc.com) or attach a current report.zip. you can take a report by pressing F7-Utilities->F7-Report

DC3IOB drives are rated ~120VDC nominal. It can NOT handle 180VDC

For DC3IOB systems, our caps were 12,000 ufd 160VDC, rectifier was rated 160VDC 25amp

Running "180VDC" motors @ 120VDC will not damage anything. The only consequence will be proportionally lower rapids.

You wrote:

I have some prints but it shows 120 VAC as the incoming power. we are using 240 VAC 3 phase Hi-leg Δ.

I'm not sure what your question is. How is your DC bus wired? Typically we pull ~89VAC off of a secondary and full wave rectify it to ~120VDC. You mentioned you have measured 97VDC, what is the AC feed into the rectifier? If you put your meter on AC and measure the DC bus, what do you measure?

Lastly, our DC3IOB/DC1 systems don't provide individual axis faults. What do you mean by?:

I have a com fault for it. also fault 3 on DC1.

[kf5pv]

Thank You Sir for your reply,


I did see about the uploading the report in the read before posting thread but was a little confused as I said;
I am not familiar with this equipment.


I attached the report to this thread. I will also email it.

Okay,
Understood. 120 VDC Bus voltage. we were running around 97 so this may help a little if I can find a tap on the Xfrm to get me a little closer.

As for the supply power question I was little confused by the prints I had just because they were supplying the DC power supply with 120 Vac. Understand it can be any power. just need same end result in voltage to rectifier.

The comm fault says the following "9008 Axis 4 Communication in fault" and "9099 message cleared"

This continueously scrolls on and off.

Thanks again

Paul

[diycncscott]

Hi Paul,

If you have the 4th axis (DC1) disconnected, please change the axis label from "A" to "N"

F1-Setup->F3-Config(pw = 137 press enter)->F2-Mach->F2-Motor

[kf5pv]

Okay Sir. Will disable the Axis As instructed.
The amin problem with my axis comm error was my fault. had fiber optic cable in wrong port from processor to Drive.

I Am not sure why but my bus voltage now is running 130 VDC. Thought maybe I caould havent damaged cap or rectifier but no A.C. present at cap. Not looking on scope however.

Thanks again for your help.


Paul