Power consumption

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Place for power consumption calculations

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Raspberry Pi 3B information pages:
https://www.raspberrypi.com/documentation/computers/raspberry-pi.html#typical-power-requirements

Power Supply

All models require a 5.1V supply, but the current required generally increases according to the model. Exactly how much current (mA) the Raspberry Pi requires is dependent on what you connect to it. The following table gives various current requirements.

Recommended PSU current capacity	Maximum total USB peripheral current draw	Typical bare-board active current consumption
2.5A	1.2A	400mA

Very high-current devices, or devices that can draw a surge current such as certain modems and USB hard disks, will still require an externally powered USB hub. The power requirements of the Raspberry Pi increase as you make use of the various interfaces on the Raspberry Pi. The GPIO pins can draw 50mA safely (note that that means 50mA distributed across all the pins: an individual GPIO pin can only safely draw 16mA), the HDMI port uses 50mA, the Camera Module requires 250mA, and keyboards and mice can take as little as 100mA or as much as 1000mA! Check the power rating of the devices you plan to connect to the Raspberry Pi and purchase a power supply accordingly. If you’re not sure, we would advise you to buy a powered USB hub.

This is the typical amount of power (in Ampere) drawn by Raspberry Pi 3 Model B during standard processes:

Boot Max	Boot Avg	Idle Avg	Video playback (H.264) Max	Video playback (H.264) Avg	Stress Max	Stress Avg	Halt current
0.75	0.35	0.30	0.55	0.33	1.34	0.85	0.10

NOTE: For these measurements we used a standard Raspberry Pi OS image (current as of 26 Feb 2016, or June 2019 for the Raspberry Pi 4), at room temperature, with the Raspberry Pi connected to a HDMI monitor, USB keyboard, and USB mouse. The Raspberry Pi 3 Model B was connected to a wireless LAN access point, the Raspberry Pi 4 was connected to Ethernet. All these power measurements are approximate and do not take into account power consumption from additional USB devices; power consumption can easily exceed these measurements if multiple additional USB devices or a HAT are connected to the Raspberry Pi.

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https://raspberrypi.stackexchange.com/questions/51615/raspberry-pi-power-limitations

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4inch TFT Touch Shield - Waveshare ILI9486

Power Supply - 5V
Max amount of power drawn during use of touch screen and displaying GUI - 140mA (measured value by Krzysztof Pokora).

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replaced by direct wifi feature in raspberry pi 3B module

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LB069W light source

Voltage[V] - 12
Power rating [W] - 0,32
Power consumption in Amper - 0.32W / 12V < 0.03A

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measured - 0.026A when it is still cold to 0.016 when warm.

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The voltage regulator needs to have parameters:

• output current - 1.34A + 0.14A = 1.48A
• input voltage - 12V
• output voltage - 5V

[LigasN]

Eventually, the whole system is powered by 4 accumulators with 2200mAh each connected in series. On the other hand, the whole system takes max (Rpi3B - 1.34A + Lights - (8x0.03A=0.24A) + Rpi camera - 0.25A + optional USB driver - 0.5A = 2,33A). For being secured I decided to be prepared for 2,5A to be taken.

[LigasN]

Soooooooooooo, the time of the battery life will be:
the capacity of batteries / current load = time
2200mAh/2,5A = 52,8 min