CB-Com CB-7520 Isolated RS-232 to RS-485 Converter

CB-Com CB-7520 is an isolated RS-232 to RS-485 converter that sits between a host device’s RS-232 port and an RS-485 field network, providing galvanic isolation to protect equipment from voltage transients and common-mode disturbances on the bus. The unit offers 3000 VDC isolation specifically on the RS-232 side, allowing the RS-485 network to be grounded or powered independently from the host equipment; it draws power from a 10–30 VDC supply with a maximum consumption of 2.2 W, making it compatible with many industrial power sources. The RS-232 interface uses a female 9-pin D connector, and the device includes an automatic self-tuner to simplify setup and ensure stable RS-485 communication in varying network conditions. This model is listed as discontinued by the manufacturer, so buyers should confirm current compatibility, supplier support, and whether newer CB-Com or compatible conversion options exist for new designs. For practitioners integrating legacy equipment, the CB-7520 provides a straightforward path to add RS-485 capability while maintaining isolation on the host side.