Rise and fall time

This procedure characterises the reaction time of the EMCO high voltage DC-DC converter, both in open and closed loop mode. Steps of different height (namely 20%, 40%, 60%, 80% and 100% of the maximum output voltage of the unit) are performed, and the evolution of voltage versus time is monitored.

This does not reflect the time required to switch the the HVPS output between the programmed voltage and 0 V (such as when changing the output from DC to Off state, or when in switching mode). However, it reflects the time required to adjust to a new voltage set point. It can be used to see how the HVPS performs compared to standard values we have defined in the data sheet.

There is no parameters to set for this test. Simply press the start button to acquire the 20 curves (5 raising edges in open loop, 5 falling edges in open loop, 5 raising edges in closed loop, 5 falling edges in closed loop).

Press start to start the acquisition

After a while, you should see the curves displayed on the graph indicators

Results of a rise/fall time acquisition (click to enlarge)

  • Once the measurement is finished:
    • Press save data to save the results in the excel file. The excel file also contains quantified data on the rise/fall time for each curve.
    • Press cancel to close the window without adding the data to the excel file.
  • The open loop results is a intrinsic characterization of the circuit. They can not be modified. The close loop results, however, are dependent of the PID coefficient, and the behaviour of the HVPS in closed loop (how it is usually used) can be modified by altering the PID coefficients.
  • Some of theĀ  open-loop raising edges (particularly the one at 100% of output PWM) may have a strange shape, with a reduction of the voltage after a while. This is normal and is a built-in safety feature of the HVPS which reduces the output voltage if it exceeds the rating of the unit.