For the electrical isolation of RS-232 (V.24) interfaces, the PSM-ME-RS232/RS232-P is the ideal solution.

3-way EMI, RFI and Transient Surge Immunity

The RS-232 interface is an asymmetric voltage interface with common signal ground for all signals. In addition to its very low signal power, a characteristic feature of the interface is that the signal ground is connected to the grounded chassis housing. This results in very little immunity to interference and a maximum range of 15 meters. Using the PSM-ME-RS232/RS232-P Serial Isolator, considerably higher immunity to interference in industrial applications can be achieved.

By isolating the TX/RX data channels and the RTS/CTS control lines the PSM-ME-RS232 Serial Isolator effectively protects your RS232 devices from transient surges, lightning strikes, ground loops and noise issues.

With their high-grade 3-way isolation between both interface sides the PSM-ME-RS232 provides a floating and interference resistant RS-232 interface for the supply and ground potential. Expensive termination devices are also protected against damage by this decoupling.

Any additional potential EMI can be removed from the transmission path by using additional PSM-ME-RS232 Serial Isolators on both device interfaces.

The PSM-ME-RS232 Serial Isolators can be wall mount AC powered or snapped onto standard DIN rails supplied with 24V DC or AC. In the case of variable cable lengths, the RS-232 connection on the field side can be established conveniently using plug-in screw terminal blocks

Serial Isolator Features

• Maximum transmission speed of 115.2 kbps


• High-quality 3-way isolation up to 2 kV (VCC, V.24 (RS-232), TTY)


• Integrated surge protection with transient discharge to the DIN rail


• Transmission speed up to 115.2 kbps


• Transmission of TxD/RxD data channels and RTS/CTS control lines


• Active data transmission indicated by separate data indicators for the transmit and receive channels


• 24 V DC or AC power supply suitable for the control cabinet