KOYO PLC with IFIX Software

Hi,
I hav Koyo 250-1 Cpu and it needs to be integerated wit IFIX scada by rs422 comm. I have introduced rs422 to usb converter for data fetching. Is it needed for inverting R+,T+ signals at Converter Rs422 input side? Suggest.

I think your question is about a four wire RS-485. The transmit on one device must connect to the receive on the other device, and + to + and - to -. Both the 250 CU and your other device should have wiring diagrams.

Tom is correct. You need to check the wiring diagrams.
Getting USB to serial devices to work correctly can be a problem. This is mainly due to the 'Recommended Standard' on RS232, RS422, RS485 and power supply. Do you have another device that you can check this converter to see if it works?
I have had allot of luck with the Sabrent devices.

This article will explain a little about serial connections:
http://accautomation.ca/heres-a-quick-way-to-connect-rs232-equipment/

Regards,
Garry
http://www.accautomation.ca