Voltlog #257 – ESP32 PIR Motion Sensor With Deep Sleep & MQTT (revB part2)

In this video I’m gonna show the second revision of my esp32, battery powered PIR motion sensor. This second revision contains some optimizations to improve deep sleep power consumption as well as to fix some of the errors I had the first revision of the pcb.

Voltlog #253 – Aneng V01A Multimeter Review & Teardown

Welcome to a new Voltlog, today it’s a multimeter review because we haven’t done one in a while and here I have the Smart Digital Multimeter which sounds like a generic name, no obvious branding on the box but granted it is featuring the multimeter on the box, it’s a color image which is not often seen on these cheap meters. On the back, the meter is shown in full black holster and we get a model number sticker, AN-V01 so this probably indicates the Aneng brand.

We’ve looked at Aneng multimeters in the past in Voltlog #114 and others and I’m gonna say this again, Aneng does not make multimeters, Aneng is just a company that rebrands existing multimeters made by other companies.

Voltlog #240 – ESP32 PIR Motion Sensor With Deep Sleep & MQTT

Welcome to a new Voltlog, in this video I’m gonna show you how I designed and built this board which functions as an esp32 based, battery powered PIR motion sensor. So I started by designing the circuit, I used some common building blocks, I added the ESP32 with it’s bypass caps, some test points and the programming circuit with auto-reset, I then added some connection points for the PIR sensor, an RGB LED because why not have a nice way to signal this is one of those very small digital RGB leds, it’s just 20x20mm, it’s connected to 3.3V even though it’s only rated for 5V so I’m hoping this is going to work even on 3.3, it’s also worth having a temperature/humidity sensor to also sense that in whichever room the node will be placed and finally the power supply circuit which is a simple low dropout regulator with an 18650 battery as the input.

I did not include a battery charger circuit on this module, because I wanted to keep things simple, I’ll have a battery socket so I can just remove the 18650 cell and charge it separately plus the whole circuit should run in sleep for extended periods of time giving me a long operating time so i wouldn’t have to charge the battery too often.

Once the schematic was finished I did the board layout in a hurry so it’s not exactly pretty or optimized

but I tried to move the esp32 antenna to the side, to place the PIR sensor in the top side as the module will probably sit vertically, I tried to place the temperature sensor in the bottom side to keep it away from any components that might get hot and also placed some isolation slots for the same reason.

You should check-out revB of this board, I made some improvements present in the video below.

Voltlog #211 – Joulescope DC Energy Analyzer Review & Teardown

Welcome to a new voltlog, today I’m excited because we’re going to take a look at an awesome piece of instrumentation. I’ve received a pre-production demo unit of the Joulescope DC Energy Analyzer.

The joulescope is a low cost precision dc energy analyser which is currently on kickstarter so check the links in the description of the video for the kickstarter campaign because it has a massive discount from the retail price. The joulescope has circuitry for measuring voltage and current, from which it can calculate power and then it can integrate power over time to calculate energy. The current measurement range is from 10A al the way down to 1nA, that’s a huge dynamic range which makes it very useful if you plan to measure the energy consumption of a device that has mixed behavior for example an esp32 that will wake up, do some activity and then go back to deep sleep.

The joulescope works with a software companion that has a multimeter view and an oscilloscope view which I find very useful because it will allow you to time correlate measurements of voltage and current. That can be extremely useful when determining the energy usage of your device.