Hello Everyone,
After years away from it, I am getting back into the hobby and started by acquiring some new toys. I just bought myself a new Rigol DP832 power supply through Saelig and it arrived well packaged and shiny as expected. I began experimenting with it and about the first thing I noticed is that under a large current load, the indicated voltage on each of the 30 vdc channels was lower by nearly half volt than what I measure with either of my Fluke multimeters (a brand new 87V and an old 77). At low current loads, all three voltage meters (the PS and the two mm's) agree exactly, but when I increase the current load to about 2.8 amps (using an old 6 ohm, 250 w resistive load), the PS voltage readings are about 0.45 volts lower than the two MM's. This behavior is identical on both PS channels 1 and 2. I used another dummy load to test at about 1.4 amps and the error was still present, albeit smaller, so the voltage error seems to be somewhat proportional to the current load. BTW, I substituted each of the multimeters to measure the current and each agreed very closely with the power supply, so the PS current measurement does not seem to be an issue.
It may be that I'm doing something wrong, but if not, then this is a pretty simple thing to be wrong with the power supply, clearly way-out-of-spec behavior. Any thoughts?