I am a bit confused by the following issue I am experiencing when trying to draw a 2.8W load using a Keysight EL34143A DC load.
I have set the range to low (8.16W).
CP mode
I provided power using my DC bench power supply and a fully charged battery as two separate tests to ensure it is nothing funny with the power source
When I try to apply 2.8W CP, the actual power draw drops to 0.8682W. When I draw say 350mW, it works perfectly. 250mW works too. 2W does not.
If I switch the unit to Medium range (35.7W), then 2.8W works without issue on the same source. Surely 2.8W << 8.16W, and looking at the specs in CP mode, Low is rated for 0.01W - 8.16W. Why would 2.8W not work in low range mode but it does in medium?
See below. Any ideas what I am missing? Perhaps slew rate on the current draw? It is set to maximum.