When I put my power supply to 5V i get 4.7V at the Unit Under Test?
This my be an Issue of Wire LOSS Voltage drop.
Power Supplies typically have a Hi and Lo Sense terminal.
The Supply my be locally sense(vendor typically have jumpers at the power supply connecting the HI Out to HI Sense and Low Out to Low Sense.)
Remove the jumper and with the HI Sense to where the UUT’s Hi Power is connected and the Lo Sense to the where the UUT’s Lo Power is connect. This will insure that When the supply is set to 5V the UUT see 5V.
Remember that across the Power Supplies Hi and Lo Terminal the voltage will typically be Higher then the Set Voltage as the Power Supply compensates for the wire loss which cause the 0.3v drop in this example.
ALSO CHECK YOUR Wire Gauge of the HI and LO output terminals.
Are you using the correct Gauge wire for your currents?
Are you using the correct Gauge wire for your currents?
(READ YOUR POWER SUPPLY Manual for correct remote sensing)
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