Serial NO. : T003003-EN
Date of Editing : 2025-09-05
Answer :
This method is suitable for scenarios with a large number of readers, extended RS485 transmission distances, or mixed connections of new and old RS485 devices. By applying proper wiring and repeater amplifier configuration, stable signal transmission and improved system reliability can be ensured.
If an existing site already has older card readers installed, and new card readers are added but cannot connect, please first rule out configuration or wiring errors. If the issue persists, try adding an RS485 repeater or a terminal resistor to eliminate communication problems.
Such issues typically occur when the connection distance is long, when the number of card readers reaches several dozen, or when RS485 devices from different brands are used. In these cases, simply adding an RS485 repeater can usually resolve the connectivity problem. The wiring method is as follows:
