Week 10: OUTPUTS¶

group assignment: • measure the power consumption of an output device

This week we used an multimeter + math to measure the wattage of a device Angela made!

Quentin¶

quentin in NODA

This week, we had a special treat to have Quentin join us in NODA!

How to Measure Power¶

!!WARNING!!

IMPROPER USE OF TOOLS CAN REULT IN ELECTRIC SHOCKS, CAUSING DAMAGE TO YOU OR YOUR MICROCONTROLLERS.

equation picture

The equation for finding the power an output devive is Power = Voltage &sdot Amps We need to measure both the voltage and the amperage of the output device.

Angela's circuit

12 V LED circuit that we used to measure power

simplified circut

Here is a simplified version of the led circut we are measuring

Measuring Voltage¶

First we put the multimeter in volatage 20 mode. We chose this because 12v led and 12v battery, and those are between 2 and 20, which are our settings.

irl photo of measuring voltage

Here, Castor is measuring the voltage using the multimeter

you set the power to power and ground to ground on either side of the led

simplified voltage

simplified it looks like this

voltage after is 11.85V, which is within normal expectations

Measuring Amps¶

irl photo of amps

Here, we’re measuring the amperage by measuring it in series. This means we had to open up the circuit with an extra jumper cable and clamp the probes accordingly

next we measure the amperage. we wire it like this

simplifies amperage

simplified it looks like this

we set the multimetes t0 amps mode, and set it to the highest setting we can, 10 amps. We cannot hurt the microcontroller or circut by setting this too high.

we have 2.34 amps!

Final Equation¶

equation

Our LED uses 2.77 watts!