rQx
Lifetime Supporting Member
Hi!
I have a VFD and a Siemens LOGO.
The VFD send the speed feedback 0-10V to my LOGO.
The LOGO send the speed setpoint 4-20mA to the VFD.
How would you set this up regarding that we use two power supplys (the VFDs and the LOGOs). Both power supply are grounded so the -24VDC have the same potential.
The examples in the manuals only state how to connect a 2-wire sensor with the same supply as the LOGO/VFD.
Naturally it works if I pull a wire from the logo to the VFD and the other way around since it have both ends grounded. But is this the best/a good solution?
Should I maybe connect the 0V on both ends?
What I am worried about is that if I connect and have reference to ground it will get noise from the VFD.
/Tim
I have a VFD and a Siemens LOGO.
The VFD send the speed feedback 0-10V to my LOGO.
The LOGO send the speed setpoint 4-20mA to the VFD.
How would you set this up regarding that we use two power supplys (the VFDs and the LOGOs). Both power supply are grounded so the -24VDC have the same potential.
The examples in the manuals only state how to connect a 2-wire sensor with the same supply as the LOGO/VFD.
Naturally it works if I pull a wire from the logo to the VFD and the other way around since it have both ends grounded. But is this the best/a good solution?
Should I maybe connect the 0V on both ends?
What I am worried about is that if I connect and have reference to ground it will get noise from the VFD.
/Tim