What are acceptable Impedance measurements for a Modbus Plus Network cable?



A properly installed Modbus Plus cable will have a measurement between 60 and 80 ohms. This measurement will be taken between pins 2 & 3 of the MB+ connector.
Improperly installed or defective cabling can have a measured value of 60 or 120 ohms.
For more information reference the Modbus Plus Planning and Installation Guide (P/N) 890 USE 100 00 for additional information.