San telequip manufactures interface converters that are used for conversion of rs232 signals to rs485/rs422. These are bi- directional devices. Rs422 and rs485 with 2-wire/4-wire configuration is available as standard. Dip switches on the front facia allow the user to select baud rate, 2-wire/4-wire configurations, etc. With a standard cable impedance @ 90 w/km the rs485 signals can be driven up to 1.2 km at a baud rate of 9600 bps. Multiple devices can be multi-dropped on the 485 side. The interface converters have provision for 230 v/1 10v ac input supply. Variants for 24 v/48 v dc and loop powered are also available. The interface converters are 3 kv galvanic and 3 kv opto-isolated with a power consumption of less than 1 w. Rts/dtr controlled converters are also available as option. Dbs female and screw terminations provide connections to the rs232 and rs485 devices. Leds for tx and rx and power are available on the front facia.
