Shown below, a XO1.5 is measuring the DC charging current of a XO1.0. The voltage is measured across a 0.8 ohm series resistor. The phono plug of one laptop has an inbuilt 680 ohm series resistor to protect against excessive voltage, the power plug of the other laptop has an inbuilt series diode to protect against reverse voltage. This circuit cannot be used for one laptop to monitor itself because the grounds must be at 2 different points. | Shown below, a XO1.5 is measuring the DC charging current of a XO1.0. The voltage is measured across a 0.8 ohm series resistor. The phono plug of one laptop has an inbuilt 680 ohm series resistor to protect against excessive voltage, the power plug of the other laptop has an inbuilt series diode to protect against reverse voltage. This circuit cannot be used for one laptop to monitor itself because the grounds must be at 2 different points. |