KEPCO EL Series Electronic Load Operator Manual P/N 243-1295 Firmware Version 4.00 to 4.xx - Manual (Page 57)

SERIES EL 071414
3-21
3.14.1 DAMPING ADJUSTMENTS
The factory default settings for damping sets the overall system damping at maximum and the
Power FET Module damping at mid-level. It should be noted that once changed, these damping
settings are stored in non-volatile memory; the new values are retained until changed again. For
most applications the factory settings should provide optimum damping, however, if you have a
special situation, damping adjustments are best made using a test set up as shown in Figure 3-
5.
Figure 3-6 shows various waveforms that may appear at the current monitor output (I-Load)
when the load is connected to a high current source and the current drawn from the source
changes rapidly following a square wave (or pulse) source connected to the E-Load input. Fig-
ure 3-6 shows the effects of changing both the System Damping and the Mode Damping. The
exact waveforms that will be seen are highly dependent on the nature of the source, the inter-
connecting cables and the various damping setting.
FIGURE 3-5. DAMPING MEASUREMENT SETUP
3.14.2 RECOMMENDED DAMPING ADJUSTMENT PROCEDURE
Damping adjustments are made using either the front panel or the SCPI Commands found in
Appendix B via either the RS-232 or USB remote interface.
System and Mode (PFM) Damping are adjusted using either the procedure detailed in PAR,
3.14.3 (front panel) or the SYST:DAMP (see PAR. B.93) and SYST:PFM:DAMP (see PAR.
B.102) command commands via remote interface. Refer to the respective paragraphs as neces-
sary.
Figure 3-6 shows sample waveforms of a properly damped EL (A) and an improperly damped
EL (B, C, D). The goal is to attain a waveform looking like A. This may not be possible and the
best that can be accomplished is C with the smallest overshoots. The waveform can be