Converts RS-232 to RS-422 or RS-485. 2,000V two-way optical isolation protects devices from power surges, spikes and more. This converter supports distances up to 4000 ft and data rates up to 115.2 kbps. Switchable modes support 2-wire RS-485, 4-wire RS-485 and full-duplex RS-422. DB9 F RS-232 input