I have two DC power supplies capable of 60V/2A for powering a hard drive. The hard drive requires 12V and a 5 V line to operate and the power supply displays the current based on the hard drive load. I would like to log this current data. When I hook up the data logger and multiplexer to channel 21 and 22. I see it reads the source(power supply) value which is 2A rather than the current at the load(hard drive). How can I log the current at the load? Thank you.