What is an RC Subber and Why Do I Need One?

FADUINO users frequently ask this type of question. FADUINO is an industrial controller based on Arduino, and since Arduino is widely used by beginners, this seems to be a common issue.

Many users who connect external relays, contactors, or pumps/motors to FADUINO report that:

"FADUINO suddenly resets when the pump starts running."

They often assume this is due to a product defect.

The Importance of the RC Snubber

When I ask them, "Did you install an RC Snubber?", they often respond with "What is that?"

An RC Snubber is an easily available electrical component that can be purchased online at a low price. It is essential for control panels that include relays or contactors.

Installation Guide

• The RC Snubber should be installed as close as possible to both ends of the coil.
• To clarify, I’ve included a reference from an EATON PLC manual.
• As you can see, RC Snubbers must be installed near the load terminals, which means they cannot be built directly into the PLC or FADUINO.
• The blue-marked areas in the diagram show the correct positions for RC Snubber installation.

If your control panel was installed by a professional electrician, chances are the RC Snubbers were already installed, since this is common knowledge among electrical technicians.

However, if you are not familiar with electrical systems, you may not even be aware of the RC Snubber's existence, leading to its absence in your setup.

"This photo was sent by a customer who is actually using an MSB product (a product similar to FADUINO). At the time, no RC Snubber was installed. The customer reported that the entire system shut down whenever the motor operated. After installing the RC Snubber, they informed us that the issue was resolved."