Thermo液相色谱U3000脱气机真空泵

SYSTEC® ZHCR VACUUM PUMP Introducing the ZHCR® (Zero Hysteresis Constant  Run) stepper motor driven vacuum pump, designed  and developed for membrane degassing of HPLC  mobile phase and other fluids used in Analytical  Instrumentation. Employing a micro-stepping closed loop vacuum  control strategy permits the pump to maintain a  constant vacuum level set-point* by varying the  RPM of the stepper motor. The pump initially runs  at a high speed which provides for a quick pull down and, as it approaches the vacuum control point, the  RPM is gradually reduced until the desired vacuum level is reached. This patented control strategy  allows the On-Line Degasser to maintain a virtually  constant vacuum that is unaffected by varying  degassing loads. As a consequence, fluctuations in  baseline due to vacuum hysteresis are eliminated  by not having the pump repeatedly stop and start  as is done in many older and existing systems

Thermo U3000液相色谱仪脱气机真空泵，货号：6040.1981