This model is specifically designed with low ripple and noise. The unit comes with a large LCD display with back light, providing accurate readout for the voltage and current values. The automatically start air fan makes it work for a long time without over heating. Adjustable outputs: 0-30V and 0-30A Variable controls for both current and voltage outputs, front AUX outputs is 5A max Input voltage: 110V Ripple noise: 100 mV Protection: Overload and overheat protection Environment: 0-40C, relative humidity. TP3030E Power Supply User Manual.