Description

RT390 is a compact microprocessor-based controller with user programmable internal structure and very wide range of application. It can be equipped with up to 3 analog and 2 discrete inputs and up to 3 relays and 2 analog outputs and can accept a whole variety of input signals including temperature, relative humidity, flow, pressure, pH, etc. Electromechanical relays, solid-state relays, or current or voltage analog outputs may be installed as control, alarm, or limit comparators. Each relay output may be programmed as time or frequency proportional or as a simple ON/OFF. The 3 analog inputs available allow special applications like positioning control, cascade controllers, pH control (with temperature compensation), etc. The internal structure consists of up to 15 functional blocks. Each functional block may calculate one of the 24 standard functions. Custom defined functions may be added. Bumpless auto/manual changeover is another feature. Network functions and hierarchical control are available with serial interface installed. Keyboard locking is possible by connection of a switch to one of the digital inputs.