Water Valve Servo Automation (part 1) | Voltlog #412

Welcome to a new video, this will be part 1 from what I expect to be a 2 or 3 part series where I show you how I designed and manufactured an automation for controlling the main water supply valve in my apartment. The first part will be related to the mechanical construction while the second part will likely be related to the electronics needed for control.

So first of all the reason why you might want to automate this is for protection in case of failure, you can detect the water leaks using other sensors and close the main valve to prevent extensive water damage. You might also want to conveniently turn it off remotely if you go on vacation for extended periods of time, stuff like that.

Now you might say there are ready made solenoid valves that run on various voltages and you can use one of those to replace an existing analog valve and at that stage you would just need a relay to turn power on or off to that valve. And that is certainly a good option for those that are building a new installation, you can certainly plan for that and install one of those solenoid valves but in my case, I would need to shut-off the building main water supply and get a plumber to install that valve which I would like to avoid. I am also aware of servo type accessories that clamp over existing valves but seem to be designed for the lever type valves so they wouldn’t work for the style of valve that I have installed.

So the first step for me was to get a spare valve,  needed it to be the exact same model, luckily I could find an identical one, it’s from this company Herz Austria so now I could take measurements of this and recreate a 3D model in Fusion 360. I could not find a 3D model for this specific model from the manufacturer so I had to recreate this but it didn’t take too long because I was only interested in the rough outside dimensions and not the intricate details on the inside.

Global Chip Shortage Solution Or Maybe Not? | Voltlog #406

Welcome to a new Voltlog, In this video I’m gonna show you one potential solution if your design uses a part that you can’t source anymore due to the global chip shortage but also the pitfalls of using this method in the case of a dc-dc converter. Please keep in mind that actual price per unit or stock availability will vary between the point I started working on this video which is a couple of months ago, the actual time when I publish it or the time that you are watching it.

Let me start with providing you a bit of context here, this is the CanLite, an ESP32 based design that I sell on my Tindie store. It’s a CAN development board, it’s got a couple of high side switches, a CAN interface, a powerful processor with Wifi Capability and an automotive rated DC_DC converter to allow the user to power this from a car 12V system.

The DC-DC converter chip that I’m using is the Texas Instruments LMR14006 and I’ve been pretty happy with using dc-dc controllers from TI over the years because they generally perform really well and they have good documentation and design resources available.

Now as you all know the chip shortage has not been kind to us and as a result I can’t find this chip anymore. If we go to Octopart which is like a search engine for electronic components, we see there is no stock with any of the major distributors for the particular part number that I was using LMR14006XDDCR. And don’t get your hopes up with Winsource or Cytek, these guys just list stock for stuff that they don’t have and even if they have it, it’s not worth going through them unless you have a high volume.

VoltLink revC CP2102N USB Serial Bridge & ESP32 Programmer | Voltlog #405

Welcome to a new Voltlog, a rather short video for today. I’m gonna be showing you the latest revision of the VoltLink USB To Serial Adapter. This is revision C and while this revision doesn’t necessarily bring any new functionality to the VoltLink it does optimize the design for manufacturing a little more which makes it easier for me to build these units.

Before I go into more details let me just quickly mention that if you would like to order one of these, they are available on Tindie and there will be links in the video description to the product page.

So like I mentioned, no new functionality added in revC, but that’s okay because I’m pretty happy with the functionality we have so far, I mean there is USB Type-C which means you no longer need to resort to the older micro usb cables, you got over current protection at 500mA, ESD protection.

We still have a high quality, high speed, usb to serial converter in the form of the CP2102N which enables baud rates up to 3M baud and this significantly improves the time you need to flash your board and you will quickly get used to this higher speed so much that when you switch to some other converter or board that only supports lower baud rate you will feel how slow that is.

We still have the 500mA rated low dropout regulator which provides 3.3V to the target board and 500mA is enough to cover the majority of boards that you will be programming. For example all of the ESP32 based boards that I design can be powered by the VoltLink while flashing firmware with no issues. Additionally I showed in a recent video that with a custom optional cable that you can order with the VoltLink you can safely flash Shelly relays without having them connected to mains voltage.

How To Flash Shelly Relays With Tasmota Or ESPHome | Voltlog #404

Welcome to a new Voltlog, in this video I’m going to show how to flash your Shelly relay with Tasmota or ESPHome, the easy way, using the VoltLink USB to serial converter. What is a Shelly relay you might ask? Well, if you are into home automation, a shelly relay is a wifi connected smart relay, built into a very compact form factor in order to fit inside electrical junction boxes like behind wall switches or wall sockets.

Hacking The IKEA VINDRIKTNING PM2.5 Sensor With Tasmota | Voltlog #394

Welcome to a new Voltlog, in this video I’m gonna show you how I hacked the IKEA PM2.5 sensor which is normally just showing good or bad values using LEDs into a fully smart wifi enabled MQTT sensor running Tasmota firmware. And while I was doing that I also added a BOSCH BME680 air quality sensor because there is so much available space inside this enclosure and it almost felt like a perfect match for the PM2.5 sensor. But before I show you how I did that, make sure to smash that like button for the youtube algorithm.

So IKEA sells this PM2.5 sensor for cheap, something like 10EUR, it runs from a 5V USB Type-C port but it only shows results using some LEDs shining from green to orange to red for very high concentration values. But if we take a look inside the sensor after removing the 4 phillips screws we discover that there is plenty of available space inside for adding our own circuitry and it appears to be using a standard PM2.5 sensor module with serial output over UART. This is then read by a small microcontroller which controls the different LEDs and handles the small fan that pulls fresh air over the sensor intake.

So with that in mind I started looking through my box of wifi modules and found this ESP8266 based module which seems like a good candidate to install in this box. If you are a regular viewer of the channel then you must know about my mailbag videos where I show all kinds of sensors and modules and in fact those videos might be your best source for discovering new and interesting electronics modules, sensors and tools so if you are new to the channel, you must check them out.

Now by installing this ESP8266 based module inside this unit, we could connect to the TX pin of the PM2.5 sensor module and just read it’s data at the same time with the on-board microcontroller. I’m not sure if this particular sensor needs any commands for initialization at start-up but in any case that would be taken care of by the on-board microcontroller and we would just be reading the sensor data.

CanLite revD And The Global Chip Shortage | Votlog #390

Welcome to a new Voltlog, in this video I’m gonna talk about the new CanLite revision D which is now ready to be ordered on my Tindie store and you’ll find a link to my Tindie store in the description below. Yes I am already at rev.D for these boards and that’s partly due to the ongoing global chip shortage which forces me to switch to a different switch with every new batch that I manufacture but I’ll get into that later, first if you don’t know what CanLite is let me tell you a few words about this board.

The idea for this board started back when I first experimented  interfacing with the CANBUS for various automotive modules like the instrument cluster, the CAN gateway. The parking sensor module, the multimedia, I wanted to see what kind of messages get transmitted on the CAN bus network, if and how I can intercept and modify those or maybe insert my own messages so basically hacking on the CAN BUS network of my car. 

I did a whole video on the subject a year ago voltlog #342 which I will link on screen if you haven’t seen that and you’re interested in the subject check it out.

So I wanted to create this little board that could be installed in a car and perform various functions on the CanBus, I chose the ESP32 as main processing unit because that’s plenty of processing power for the task on hand, it’s also cheap, it has wifi and built-in CAN peripherals so it was a logical choice for me to use it. 

I still needed to add an external CAN transceiver to generate the differential voltage levels for the actual physical link and while I was there I also threw in an automotive grade buck regulator and a couple of automotive grade high-side switches just in case I needed to switch a load, something like a light or a motor, or whatever you might need cause these automotive high-side switches are pretty robust and you can drive pretty much anything you want with them.

And this brings me to the reason for revD, I’m sure you are aware of the ongoing global chip shortage and how car manufacturers have to stop their manufacturing plants because they can’t get the chips they need.. Well, guess where that left with my automotive high-side switches and automotive-buck regulator?

Yeah not a great choice of parts when it comes to availability, I mean, January 2023? That’s like 14 months away just for the buck regulator, all while people keep emailing me constantly to ask about the availability of the CanLite boards. The same thing could be said about the high-side switches I was using, they couldn’t be found anywhere and that’s not the only problem.

You can hardly find any alternative parts either, I’ve spent hours and hours trying to find replacements on Digikey and mouser and all I could find is low stock of parts that cost 10 times as much and come in much larger packages, but in the end my  efforts paid off and I managed to find these, the BTS452T from infineon and although these have a lower maximum switch current, I had to settle for these, I mean 1.8A per channel is still plenty of current to be useful and we still get the nice features like over temp protection, over-current protection and general transient protection that these automotive switches feature.

I also had to go for a new inductor, which was slightly different, because that wasn’t available in stock either and don’t get me started on the lack of standardization when it comes to these surface mount inductor package, it’s like every time I need to use an inductor I also have to design a new footprint cause they are never the same exact size.

Start Hacking The CAN Bus With The ESP32 CanLite Board – Voltlog #370

Welcome to a new Voltlog project video, today I’m gonna be presenting this little guy called ESP32 CanLite. This is a CAN hacking / development board based on an ESP32 and this is the results of my adventures into hacking the CAN network on my vw golf. I have not made any significant progress on the actual task of hacking the can bus other than what’s shown in Voltlog #342 simply because I got very busy with the professional work I do, consulting for various clients, you know just designing and building electronics but nonetheless I found the time to design and refine this board because this is already the second revision.

VW Can Bus Hacking With SavvyCan & Cantact – Voltlog #342

In this video I’m gonna walk you through the process that I use for hacking a VW cluster CAN bus(PQ35 platform). The tools that I’m going to be using today are very accessible price wise and open source on top of that. As hardware I’m going to be using the Cantact usb to can bus adapter, this is going to allow a computer and operating system to access and communicate on the CAN BUS. As software I’m going to be using Savvycan which is once again an open source GUI tool for hacking and reverse engineering CAN BUS data.