Keysight N3300A DC Electronic Load

[EVlab]

I was wondering some loads of other brands have constant power mode and the Keysight doesn't. Does someone know why?

Does someone has practical experience using a N3300A in constant power operation?

I thought of a software implementation: Query the N3300A over GPIB for actual voltage and then set a corresponding current to achieve constant power load. But is there a more elegant way?

Best, Simon

[alm]

Reading the current / voltage monitor outputs with an external control loop that controls the analog programming input might be more elegant and achieve a faster response time, but might be harder to get stable.

[nctnico]

Oddly enough there is a multiplier in the DC load modules so it would be possible to do constant power. From the schematics it seems that the control loop is implemented in a CPLD device. Perhaps there was no room for a constant power mode or it was deemed too complicated.
These are very nice loads though. I've got the small (2 slot) mainframe and I wouldn't mind acquiring another one if the price is right.

[alm]

The manual mentions that the over power limit is a software limit. So not sure what they would need a multiplier for? Unless it is to trigger the software flag (that acts like a fold-back limit).

[dacman]

Constant Power in some electronic loads, such as the BK 8500 series, is a calculation (along with Constant Resistance).