HEMSA-T-014 PCI multi-port serial adaptor with photoelectric isolation is compatible with RS-485/422 standard. It converts PCI signal to balanced differential RS-485/422 signal. With built-in photoelectric isolator, it provides as high as 2,500 Vrms isolated voltage. This device has lightning and ESD protection, which provides 2,000V each wire with lightning surge protection. This adaptor also has surge voltage and transient over-voltage protection on circuit which could be caused by all reasons. The tiny inter-electrode capacitance ensures high speed transmission for RS-485/422 ports.