The PL series achieves an exceptional power density for a linear regulated power supply offering up to 90 watts from a ¼ rack 3U sized casing. For rack-mount application, up to four units can be mounted into a single slot. The PL series generates relatively little heat through the use of an advanced phase controlled pre-regulator. This gives it significantly higher energy efficiency than conventional linear regulated designs, particularly when supplying lower voltages. The internal heat-sinks use fan-assisted convection cooling in order to remove the heat with minimal fan noise. The PL series introduces S-Lock. This offers not complete security and exceptional stability with each setting controlled by an instrumentation quality DAC V-Span function of the PL series allows the user to redefine the end-stop values of the voltage control to define a specific voltage range.