Four Relays Four HV Inputs 8-Layer Stackable HAT for Raspberry Pi

I bought this some time ago and thought I must write a review as it would be best for someone to get a little inside knowledge before buying. For this tool, it is wise you use the brass supports provided to you to hold the HAT in place on your Raspberry Pi UNLESS you are 3D printing the case provided on their website (in the photos provided) - you can’t use the brass supports with the case. The reason for doing this is you must not rely on the GPIO pins to support this hardware in any way, even though they seem sturdy enough, it is not wise to do so. I bought the DIN rail mount kit on their website as I needed to use this in an electrical cabinet setting and this was a perfect fit, with the case installed as well. I would recommend only using one din rail mount as opposed to the two that I used as it is very difficult to remove the hardware from an electrical cabinet on something so small with two mounts, unless you plan on not removing the hardware for a very long time. The case was printed using ONYX filament with .15mm layer height and took about 26 hours to print in total - very good quality. I used this hardware in a counting application and had to code the software myself on python v3.9, I have provided a snippet of the code on the company’s GITHUB webpage for this hardware in case you’re interested. The code is robust and meant for inductive sensors that count on a frequency instead of an instance but converted the frequency to an instance counter. This should be helpful for any industrial application. The creator of the GITHUB page, Alexander is more than enough help. You can find his email on the GITHUB website. I recommend this hardware and specifically recommend this company, Sequent Microsystems.

I have used several Sequent Microsystem Hats and they all work well. The Home Automation, 16 digital input, 16 temperature input and this 4 relay and 4 input card work very well together. Programming in Python is simple and input and output works well. Support on any issues are handled quickly and the developers have added features I asked for. Pricing to also great and the connectors are top notch. Highly recommend all their products.