Question about DIO output

Topics about the Hardware of Revolution Pi
Post Reply
jejmule
Posts: 2
Joined: 11 May 2021, 12:44

Question about DIO output

Post by jejmule »

Hello,

I am working on a project where I control two frequency inverters Mitsubshi FR-D700 and Hitachi WJ200. I have attached input description of both inverter, both inverter are configured with sourcings inputs.
I have a 24v external power supply connected on X2 connector. I am using O1 and O2 to drive FR-D700 inverter and O3 and O4 to drive WJ200 inverter. power supply GND is connected to pin SD and L of inverter (internal GND).

When the output are configured in High-side mode i have the following behavior : when I am driving WJ200 inverter I have also a current flowing into FR-D700 even if there related output are low.
The issue is solved if I am using push-pull mode.

Can you explain me why I have this behavior? Why current is flowing in O3-O4 when they are in high impedance state while O1 or O2 is in high state.

Let me know if my problem is clear or not, I can make a schematic connection diagram if required
Attachments
FR-D700-input.PNG
FR-D700-input.PNG (41.72 KiB) Viewed 2415 times
WJ200-input.PNG
WJ200-input.PNG (22.09 KiB) Viewed 2415 times
User avatar
dirk
KUNBUS
Posts: 2174
Joined: 15 Dec 2016, 13:19

Re: Question about DIO output

Post by dirk »

Hi jejmule,
Thank you very much for your detailed error report.
Please check the wiring. You could also install coupling relays between the DIO outputs and inverter inputs.
Post Reply