High-Voltage DC Monitoring via Raspberry Pi Zero

INTRODUCTION

We have been using Raspberry Pi for years. We needed a high-voltage monitoring system in one of our projects. We thought Raspberry Pi would be affected by the distorting effects of high voltage, but we wanted to give it a try. Afterwards, we ensured the Raspberry Pi to read up to 1600VDC by isolating it from the ground and using LC, RC filters.

Instead of expensive Windows-based industrial PCs, you can use Raspberry Pi Zero that you will not pay any license fees. It is so important for automation companies.

Since there is no Ethernet on Raspberry Pi Zero on the device, SPI-based Ethernet converter is used. DC voltage is provided to read with completely isolated OPAMP. Since there is no analog input device on Raspberry Pi, 12-bit ADC is used.

We tested the device as follows:

As you can see in the video, it is provided to read the 1500VDC from the two 750V voltage power supplies connected to the Raspberry Pi Zero device without being affected by any noise. Even the OLED screen can continue typing without any blink.

The table below shows the voltages at the DC voltage and OPAMP output from the field.

We can calculate the voltage amount per 1V as follows:

Warm-up performances are quite good as high-power resistors are used as a voltage divider. The picture was shared at below was taken 1 hour after the start of the test.

RESULT

As a result; If you pay attention to the design of Raspberry Pi Zero, there will be no difference from any processor. Of course, we can design an industrial Raspberry Pi Shield for you.

This device will be used for current and voltage monitoring in Solar Power Plants.

I wish you healthy days..

WARNING

If you do not have professional technical knowledge, please do not try.