The instrument E 90 /1 is designed for easy installation and suitable for usage in pharmaceutical, paint , chemical industries and potentially explosive environments. Complete digital programming is possible through the front end of the instrument through RS232 or RS422 / RS485, MODBUS RTU or ASCII protocols. E 90/1 is also interfaced with PLCs via Profibus-DP - installable as an option directly. Intrinsically safe barriers are also used to house into the deflagration case of the instrument.