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VFD Control outputs max. 5V ( AXBB-E)

PostPosted: Sat Nov 13, 2021 12:09 pm
by GeorgS
Hello together,
Yesterday I was able to replace the chinese XHC usb Motion card by the AXBB-E.
Everything seems to work fine, except the spindle control. I can measure max. 5V between 5v- and AO1. So My 10V CFD control doesn't run the spindle on 100%, just 50%.

Jumper on AXBB-E is ON. Tried to pull the jumper Off, then I get a maximum of 3V.
See my settings in the attached pictures. Do you have any ideas?

many thanks!

Georg

Re: VFD Control outputs max. 5V ( AXBB-E)

PostPosted: Sat Nov 13, 2021 12:24 pm
by GeorgS
ps. of course I set the rpm to 24000 when testing..

Re: VFD Control outputs max. 5V ( AXBB-E)

PostPosted: Sat Nov 13, 2021 12:37 pm
by cncdrive
Hi,

Between which points do you measure the Voltage? AO1 and 5V0 (ground)?
Also can you measure the Voltage with the analog output not connected to the VFD analog input.

And also check and make sure that the max,. PWM % in the spindle settings is 100% and that you programmed the maximum possible S value when measuring.

Re: VFD Control outputs max. 5V ( AXBB-E)

PostPosted: Sat Nov 13, 2021 8:56 pm
by GeorgS
Hi,

Thanks for your quick reply! As I wrote and showed in the pictures, I measured between 5V0 and AO1.

RPM is set to 24000 with M3 S24000 code.


I just checked again, you are right! without the VFD I get 10.0 volts, after connecting the VFD I get 5V only. I still measure 5.20V and 24.20 V for the input voltages.

VFD inverter is this one: https://cncu.co.za/EasyRoute-CNC-Router ... Manual.pdf

connection AXBB-E--> Inverter:

5V0 --> ACM
AO1-->VI

Georg

Re: VFD Control outputs max. 5V ( AXBB-E)

PostPosted: Sun Nov 14, 2021 6:57 am
by cncdrive
Try to put an about 1kiloOhm resistor between the AO1 and the analog inut of the VFD.
I mean that instead of connecting them with a wire connect them through the resistor.

Re: VFD Control outputs max. 5V ( AXBB-E)

PostPosted: Tue Nov 16, 2021 11:56 pm
by GeorgS
Amazon resistor kit arrived, but did not help.

I found the problem, with this spindle you really have to use a separate cable for the rpm control, first I had a shielded cable aswell but also with the spindle relay wires inside.
Now I used a second shielded cable with ferrite core and an additional small capacitor as recommended by the vfd manufacturer and finally full throttle shows up :-)

My first impressions on UCCNC and the AXBB-E:

I really like the AXBB-E but it seems that the JOG is delayed by this device. I have experience with 3 different USB controllers on other machines ( UC100, xhc motion card and CNCgraf controller) there I have immediate response to the Jog inputs ( keyboard inputs)
The AXBB-E seems to have a delay, this forces you to pay more attention or slow down Jog more then necessary when manually setting workpiece zero. Same behavior also in Mach3 with the AXBB-E. Will try Mach4 these days. I am searching for the program that allows me to run the smoothest 3D toolpath. Mach 3 allows you to run very smooth and fast, but then your accuracy is horrible. UCCNC seems to run smooth but decreases speed where it also could keep going faster in my opinion. I also wonder why UCCNC forces me to close the program when switching off the machine/ controller. But I really have to say this is probably the most easy to configure Cnc control program I've ever had. With all settings you need :-) I read the manual but I'm pretty sure configuring the machine would have been successful without.

Re: VFD Control outputs max. 5V ( AXBB-E)

PostPosted: Wed Nov 17, 2021 3:16 pm
by cncdrive
The UCCNC has path deviation control, mach3 does not have that.
So, with the UCCNC you can setup the constant valocity parameters with telling the software how much path error it is allowed to make.
In mach3 you cannot tell the software how much error it can make to keep the feedrate, so mach3 doing it by it's own ideas which is kind of a "joke" as this is a CNC machine where it is very important to know the tolerances.
Ofcourse with wooden and art jobs you can loose the CV parameters, in other words you can allow the UCCNC to make larger errors, so then it has more freedom to optimise the toolpath with keeping the feedrate better.
And if you need tight tolerances then you can use lower CV parameters so the software will have less freedom to run fast, but it will keep the tight tolerances.

And the UCCNC has not much delay with the jogging, it should be less than 20msec which is low enough that it should be not noticable.
And Mach3 has much more delay with the jogging.
Isn't it possible that your computer is overloaded? That could cause slower GUI response, slower communication response and so the jogging will also response slower.

Re: VFD Control outputs max. 5V ( AXBB-E)

PostPosted: Thu Nov 18, 2021 9:26 am
by GeorgS
Thanks for your reply.

I just wonder why also in Mach3 the jog is delayed with the axbb-e, if I use the same mache settings but with XHC usb controller, I don't have any delay at all.
perhaps it's on the computers side, but then it would be a problem with the ethernet connection only.

Georg