In some industry (electronics, pharmaceutical, food preparation, pneumatic conveying, etc.) or for installations with external pipe work, a pressure DewPoint of +3°C from a refrigerant dryer is not sufficient. For these applications, a heatless adsorption dryer is required supplying compressed air at a pressure DewPoint of down -70 °C. Heatless dryers are compact and have low purchase and maintenance costs. The HDT heatless adsorption dryers consist of two parallel vessels filled with adsorption material (molecular sieve). While compressed air is dried in one tower, the second saturated tower, having just come off line, is regenerated. A small amount of dried compressed air is used for this purpose. Return to the technical data
Standard for all models HDT 3-25 dryers are supplied with DDC12 electronic instrument. Internal micro-processor permits the selection of working pressure DewPoint (-20°C, -40°C or -70°C), while synoptic panel informs the operator of the working phases of the dryer. From model HDT 30 the dryers are equipped with DDC15 electronic instrument. The controller, developed from previous model, performs a careful and precise management of the dryer, through following functions : - the selection of working pressure DewPoint (-20°C, -40°C or -70°C); - the detailed information of dryer function and possible faults by using synoptic panel; - the indication of the load factor settings and/or the real DewPoint (if optional DewPoint probe is installed), via the ten LED display bar; - the selection of dryer operation mode (FIX : with fix cycle time, DPD : with cycle time proportional to effective working load - if optional DewPoint probe is installed, TEST : for diagnostic cycle - the dryer runs step-by-step in order to insure easy troubleshooting in order to assist in repairs); - the control and the management of three different energy saving levels (the load factor set by the operator, dryer operation according to air compressor load, or the load depending on real DewPoint, if optional DewPoint probe is installed); - the diagnostics of possible fault/alarm : maintenance required, tower cycle has not taken place in correct way (if optional pressure-switch kit is installed), the pressure DewPoint is too high (if optional DewPoint probe is installed); - the control of programmed maintenance operation. DDC 15 includes a RJ45 serial port (RS 232 standard) allowing the connection to a network managed by PC or PLC. Optional for all models IP55 Pressure-Switches in order to enable “FAIL TO SWITCH” alarm of DDC15 Controller. Optional for all models Pressure DewPoint meter, including sampling system, wired to DDC15 Controller. Calibration certificate is included. Optional for all models Pressure-Switches + Pressure DewPoint meter Kit.