×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

*
*
*
*

Thanks. We have received your request and will respond promptly.

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

Reverse current protection diodes and r/c snubbers

thread277-194502

Reverse current protection diodes and r/c snubbers

Reverse current protection diodes and r/c snubbers

(OP)
Question about protecting plc contacts and other sensitive components from inductive loads. Specifically solenoids that actuate air cylinders (24vdc), electric clutch coils (24vdc and 110vac, and contactor coils(24vdc).
When is it best to use a simple diode, and when is it best to use a resistor/capacitor snubber or suppressor? I've heard diode obviously for the DC stuff and snubber for the ac stuff. I understand a diode won't help me with the ac circuit, but I've seen both diodes and r/c snubbers on dc stuff.
I always use one or the other but not always sure which is best? Any insight would be greatly appreciated.

RE: Reverse current protection diodes and r/c snubbers

You use a diode in DC cases as it is the simplest and most effective technique.

You cannot use a diode in AC for that solution so you use snubbers, (cap/resistor).

Snubbers dissipate power so are less desirable but they work very well.

A suppressor works well and dissipates much less power, only when actually 'suppressing'.  Often they have a shorter life as they are mechanical and wear out.

Did this answer your question?

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Reverse current protection diodes and r/c snubbers

Snubbers are a wide field. Power supplies, motor control and transient suppression in switches are the more important applications. There is a lot of written material.

http://www.multi-contact.com.sg/elesta/images/Technical%20Information.pdf
http://focus.ti.com/lit/an/slup100/slup100.pdf
http://www.industrologic.com/mechrela.htm

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

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

Resources

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