[DelMar63]

Hello guys!
I just got a HY VFD model HY02D223B 2.2 Kw with 2.2 Kw spindle. I managed to make the right setup and I work it from Mach3. Turn on/off and regulate the speed too. But I have a problem of accurancy. Meaning that when I measure the output of BoB at 0-10 pins without connections made, the BoB send the right signal. That means 10 v to full speed 24000rpm, 5v at 12000rpm etc. But when I establish the connection to VFD at ACM+VI pins I take the measurement again and at full speed the signal is 8.6v and lower than 4v at 12000rpm. Of course the VFD shows at full rpm around 20520 and at half speed somewhere around 9850rpm. Mine BoB is working in a range of 12-24 v and I provide 19 v @ 3 A and at USB 5 v @ 15 A. At my first attemp I used a shielded cable of 2 pairs for the signal and I also tried to erth the shield, but then the voltage was decreasing a litle bit. Then I changed the cables with a twisted one cat5 with 4 pairs, but not luck at all. the same problem with low voltage at full speed and at lower speeds too. Is there any logical explanation or something I can do to fix this problem ?
Note: Every time to I turn the control to VFD panel and use the potensiometer, everything works fine.

[mactec54]

Hello guys!
I just got a HY VFD model HY02D223B 2.2 Kw with 2.2 Kw spindle. I managed to make the right setup and I work it from Mach3. Turn on/off and regulate the speed too. But I have a problem of accurancy. Meaning that when I measure the output of BoB at 0-10 pins without connections made, the BoB send the right signal. That means 10 v to full speed 24000rpm, 5v at 12000rpm etc. But when I establish the connection to VFD at ACM+VI pins I take the measurement again and at full speed the signal is 8.6v and lower than 4v at 12000rpm. Of course the VFD shows at full rpm around 20520 and at half speed somewhere around 9850rpm. Mine BoB is working in a range of 12-24 v and I provide 19 v @ 3 A and at USB 5 v @ 15 A. At my first attemp I used a shielded cable of 2 pairs for the signal and I also tried to erth the shield, but then the voltage was decreasing a litle bit. Then I changed the cables with a twisted one cat5 with 4 pairs, but not luck at all. the same problem with low voltage at full speed and at lower speeds too. Is there any logical explanation or something I can do to fix this problem ?
Note: Every time to I turn the control to VFD panel and use the potensiometer, everything works fine.

How where you Grounding the Shield

Can you check at the end of the Cable before it connects to the VFD and see if the voltage is correct

[DelMar63]

Grounding the shield. I left open the shield (no connection) at the BoB side and connected the shield to the other end of cable at the earth of VFD. This is the way I followed to ground the shield of the motor cable too.
As for measuring voltage at the other end before connect them to VFD, I haven't done it exactly the way you refer but I measured the voltage once on the BoB while the connection was established at both ends but the inverter was switched off while I was using Mach3 and the result was at full speed around 9,76 v and accordingly the half speed. It seems to me like the inverter drawing some of the voltage. As I already said, I noticed a wear behavior of the voltage. Every time I was contacting the shield to the earth of VFD, the voltage was decreasing a little bit. Also every time I was touching the positive pin of the BoB (I refer to 0-10) the voltage was increasing just a little bit.

[mactec54]

Grounding the shield. I left open the shield (no connection) at the BoB side and connected the shield to the other end of cable at the earth of VFD. This is the way I followed to ground the shield of the motor cable too.
As for measuring voltage at the other end before connect them to VFD, I haven't done it exactly the way you refer but I measured the voltage once on the BoB while the connection was established at both ends but the inverter was switched off while I was using Mach3 and the result was at full speed around 9,76 v and accordingly the half speed. It seems to me like the inverter drawing some of the voltage. As I already said, I noticed a wear behavior of the voltage. Every time I was contacting the shield to the earth of VFD, the voltage was decreasing a little bit. Also every time I was touching the positive pin of the BoB (I refer to 0-10) the voltage was increasing just a little bit.

The shield should not be connected to the Ground / Earth of the VFD Drive this would be adding noise into the cable the same as the VFD to Spindle Both ends must be connected to Ground / Earth Plane

You directly connect the shield Grounds / Earth to the Ground Plane the metal Case / cabinet Etc here are some examples of how it is needed to be connected

You also need to add a EMI Power Filter close to the VFD Drives input Power supply Here is one you should have TDK Lambda RSEN 2030L

[DelMar63]

Ok I got it. I will configure the shield grounding this way. But this dosn't solve my problem. Lets forget the shield for a while. My problem is that or the BoB should provide more voltage from its PWM or VFD drawing more voltage from BoB's PWM, that doesn't allow PWM to provide 10v at max speed or 400 Hz. It gives 7.8v @ full speed when is connected to VFD and the VFD is ON and arrives at 9.76 @ full speed when is connected to VFD and the VFD is OFF.
I don't understand it. I probably should buy a second BoB to test if mine is not ok.
Thank you very much for your time and your guide lines for earthing the shield.

[mactec54]

Ok I got it. I will configure the shield grounding this way. But this dosn't solve my problem. Lets forget the shield for a while. My problem is that or the BoB should provide more voltage from its PWM or VFD drawing more voltage from BoB's PWM, that doesn't allow PWM to provide 10v at max speed or 400 Hz. It gives 7.8v @ full speed when is connected to VFD and the VFD is ON and arrives at 9.76 @ full speed when is connected to VFD and the VFD is OFF.
I don't understand it. I probably should buy a second BoB to test if mine is not ok.
Thank you very much for your time and your guide lines for earthing the shield.

This is quite a common problem with some Breakout Boards that don't have a Pot to adjust the output voltage, some VFD Drives you can compensate with some Parameter adjustments to compensate for the low input voltage, check the 0-10v Filters

It can be done by manual means as well if the VFD Drive does not have any Parameter adjustment, connect a remote pot to the VFD and use that to compensate. Or regulate the analog 0-10 Volt down to a 0- 5v output and change the VFD Drive Parameters to be a 0-5v control this will work the same as a 0-10v just at a lower voltage

[DelMar63]

You made my day! I was wondering how could I raise the voltage and I never thought to lower it. Yes you are absolute right. I will update soon as get this done. Many thanks.