Some Brainboxes Serial devices are appended with the words Opto – Isolated. It may be the case that cards used in certain environments are susceptible to large surges of electricity which may potentially damage the card or the PC.

Opto Isolated cards are isolated so that sudden surges in (on the wire) electricity (eg. lightning) do not damage the PC in which the cards are housed.

RS232, 422, 485 >>