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7. Amp-Minute operation: accessible via M10; once activated, the user simply inputs the total amp-minute, the output
is disabled once the total amp-minute is reached; the user can stop and resume the process anytime using F4 key.
8. Timer operation: accessible via M9; once activated, the user simply inputs the duration of operation in minutes, the
output is disabled once the time lapsed is done; the user can stop and resume the process anytime using F4 key.
9. Voltage ramp: accessible via M8; voltage ramp is completed in 1000 steps (customizable by modifying the
Arduino sketch); the program asks the user to define the start and finish voltage, and step size in milliseconds (the
system adds about 39 mS to the step delay, so a step size of 1 mS results in about 40 mS in actual step size).
10. Automatic battery charger: enabled/disabled via M7; once activated, the user needs to input the start voltage
(below which the battery charging is initiated) and cut-off charging current. The power supply monitors the
voltage of the battery continuously, turning the output on when battery voltage falls below start voltage, and
stopping the output once the current falls below the cut-off current limit. The program also keeps track of
amp-hour of charging, as well as detailed voltage and current data.
11. Digital Voltmeter: enabled/disabled via M6; Once enabled, the voltage between the “Remote In” connector and
ground is measured and displayed on the first line of the LCD display as “V=x.xxx”. You can press M6 again to
disable this function. Similarly, if the output is disabled, you can also connect an external voltage between the +
terminal and ground to measure it. Note: both of these features can only read positive voltage.
12. RS485 communication & parallel operation of multiple power supplies: as proof of capability, we have
implemented RS485 communication between two power supplies, and allow them to operate as master/slave to
