Unmatched Precision, Unrivalled Performance The QL series II provides the highest performance levels available in a laboratory power supply. Voltage and current are controlled using 16 bit DACs enabling voltages to be set to 1mV resolution even at full output. Indeed, the accuracy is sufficient for the PSU to be used as a calibration source for some hand-held DMMs. The QL series II uses pure linear technology and offers unrivalled performance in terms of regulation, output noise and dynamics. Line and load regulation are close to the limit of measurement. Output noise is less than 350μV rms in CV mode and down to 20μA rms in CI mode. Recovery time from transient current pulses is better than 50μs. It provides full remote sense capability via dedicated sense terminals. Remote sense is essential to maintain precise regulation at the load. When remote sense is not required, internal local sensing can be selected at the touch of a button. Multiple Ranges for Greater Flexibility The QL series II provides multiple ranges for increased current capability at lower voltages. The main range offers 0 to 35 Volts at up to 3 Amps (QL355) or 0 to 56 Volts at up to 2 Amps (QL564). The higher current range provides up to 5 Amps for voltages up to 15V (QL355) or 4 Amps for voltages up to 25V (QL564). A further low current range provides enhanced current setting and measurement resolution of 0·1mA. The product of voltage and current can be displayed at any time by pressing the VxA button. The power is displayed to a resolution of 0·01 Watts. Fast, Simple and Safe to use The user interface of the QL series II has been carefully designed to provide rapid control whilst guarding against any possibility of error. Voltage and current setting can be performed either by direct numeric entry or, for applications where the voltage or current must be gradually changed, by using the quasi-analogue Jog control. To enable the current limit to be set before connecting the load, the limit setting is displayed when the output is off. Pressing the View Limits key at any time provides a temporary display of the limit values allowing precise adjustment to also be made with the output on. Setting Memories for Added Convenience The QL series II provides storage of up to 50 power supply sets-ups in non-volatile memory for each main output, plus (T models only) a further 50 set-ups for linked mode operation, plus 10 set-ups for the auxiliary output. Upon mains switch-off, the set-up of the PSU is saved and is automatically restored at switch-on. OVP and OCP Trips with 'Alarm' Output The QL series II provides fully adjustable over-voltage and over-current trips which can be used both as a fail-safe against accidental mis-setting and as a protection against inappropriate load conditions. In addition to turning the output off, a trip condition switches the rear panel alarm signal enabling other equipment to be controlled. For complete protection of the power supply, the trip will also be operated by over-temperature or excess voltage on the sense terminals. Auxiliary Output with Fully Variable Voltage (T models) The QL series II triple output power supplies incorporate an auxiliary output which is fully variable between 1 volt and 6 volts to a resolution of 0.01V, and has a current capability of 3 amps. A front panel button enables to voltage and current for the auxiliary output to be viewed on the Output 1 display whenever required.