. .	Optical Isolation ISA DMX-512 PC-Interface Card 1512B, 1512C

Why opto-isolated?

Optical isolation provides the best protection possible of delicate electronic equipment. This includes your PC, which could easily be damaged by minor stray currents. While damage of hardware components is to be considered the worst case happening, a damage of software running on your system is indeed very likely- the system crashes and you are losing control.

The optical isolation of our cards has been designed to protect your valuable PC against error conditions resulting from stray currents, ground loops, spiky DMX nets etc. It has not been designed to block high voltage surges but to provide an isolated, potential-free interface connection. While isolated DMX ports have not been required by existing protocols (USITT DMX512/1990 and DIN56930-2), new revisions such as USITT DMX512/2000 will explicitly describe optically isolated ports.

Block circuit diagram of an optically isolated output driver. Whila data information are transmitted optically (yellow), erroneous or dangerous currents are blocked at the optical isolation barrier.

A DMX receiver can be built similar to the isolated DMX driver. Our PC interface card 1512C combines both, driver and receiver circuit, for each port. As both ports use their own isolation barrier, there is no coupling between both ports, which provides ultimate security on stage.

Block circuit diagram of an optically isolated DMX receiver.