Hello,
I'm doing a project with Arduino and I want to calculate how much energy the system needs for 1 Hour.
The parts of my System is:
I have the datasheet for every component but I'm not sure for what should I check.
The power supply or current supply? Or both?
When i find the values, then all I have to do is to calculate the total sum?
Thank you in advance.
You add up the current consumption of each part and multiply by the voltage to give the power in Watts. So, if the total required current is 150mA and the supply voltage is 5V then the power consumption is 0.15 * 5 = 0.75W. That simply translates to 0.75Wh per hour.
Or, if you are feeding it from a battery and want to know the battery life then divide the capacity of the battery in Ah by the load current, so in this case with a 3Ah battery 3 / 0.15 = 20 hours.
There are 2, possibly different, values for the current; the one read from the data sheet and the one you measure with real equipment actually working.
My experience is that using datasheet figures does not reveal an accurate picture of power used.
Measuring it with a multimeter is much more useful for me.
The power consumption of GPSs in particular can vary significantly when in use.
Thank you very much for the answers!
Measuring with multimiter, the final result would be less or more than the calculated from datasheets?
I think that datasheets show values for the most demanding situations, when there is only one value and not min-max.
Measuring with multimiter, the final result would be less or more than the calculated from datasheets?
I don't know. If you assume your project will require more than the datasheet suggests then if it actually requires less it won't be a problem.
The data sheet gives a (generally pretty good) estimate of the power consumed by that device.
GPS modules will use more power when you ask them to continuously track the location than if it's just now and then getting a fix.
The display itself hardly uses anything (easily <1 mA), the LED of the backlight draws a lot more current (typically about 10 mA).
The relay of course only uses current when it's on (50-100 mA is typical for a 5V coil).