Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Solenoid Coil Whine / Resonance (Undervoltage Release Coil of Circuit Breaker)

Solenoid Coil Whine / Resonance (Undervoltage Release Coil of Circuit Breaker)

Solenoid Coil Whine / Resonance (Undervoltage Release Coil of Circuit Breaker)

Does anyone know as to whether there is a means to reduce the resonance noise produce from a AC solenoid (in this particular case the solenoid is a undervoltage release coil installed in a circuit breaker). I have been told by the manufacture that the coil is 240Vac 50Hz rated and that the noise is normal which I question. I have measured the power supply voltage and it is 244Vac at 50Hz.

Please see link for video of the noise produced by the solenoid.


RE: Solenoid Coil Whine / Resonance (Undervoltage Release Coil of Circuit Breaker)

Sounds / looks like the moving armature isn't cleanly mating with the fixed yoke, and there's an air-gap which allows a little vibration due to the AC supply. When you apply a little pressure it quietens down because you're damping out the vibration. I don't see it as a big problem - and it's by no means uncommon in contactors - but I can understand why it has been questioned. Not much you can do, unless you fancy stripping down the UVR to component level and using a surface grinder to very carefully true up the mating faces of the armature and yoke. Get this wrong and you could ruin the UVR, so think carefully before attempting this.

RE: Solenoid Coil Whine / Resonance (Undervoltage Release Coil of Circuit Breaker)

It's not resonance it's, as Scotty said, the armature not seated fully. Either the mating faces are deformed, there is some debris in between the faces (it can be very little), or (most likely) the secondary assembly mechanisms are out of spec and not allowing the armature to fully 'seal'. I would NOT put that into service. I have seen coils that make that amount of noise melt. This is because if the armature in not fully seated the coil is drawing more current than designed for as the maximum inductance is not being reached when the armature is not fully seated.

Keith Cress
kcress - http://www.flaminsystems.com

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login


Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close