Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

surface mount resistors

Posted on 2016-07-24
7
Medium Priority
?
164 Views
Last Modified: 2016-07-24
I am trying to repair a circuit board where several of the surface mount resistors have come lose.
I am trying measure the resistance, but the measured values don't quite match what is stamped on top.

The resistors that have "180" on top, almost exactly have that as a measured resistance ohms.

The resistors that have a value of "510" stamped on top, have a measured value of "50".
Is there a implied decimal point ??
0
Comment
Question by:sidwelle
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 4
  • 2
7 Comments
 
LVL 98

Expert Comment

by:John Hurst
ID: 41726835
Is there another resistor of the same stated value to measure?  Unless there is a K or M or some other marking, you would expect the resistor in question to be 510 ohms, just like the 180 ohm resistor. There is not a standard for printed values but markings usually make it clear.

You need either a comparable resistor or manufacturer spec sheet to be sure.
0
 
LVL 12

Expert Comment

by:funwithdotnet
ID: 41726851
Ignoring measurement technique- a number may match or be totally unrelated to resistance. You can't count on it. Even a match can have quite a bit of tolerance.  *If the package is not charred or damaged and is connected properly, there is a 99%+ chance that it will work properly, regardless of the measurement. *A rule of thumb from way back in my circuit component troubleshooting & repair days.
0
 
LVL 98

Expert Comment

by:John Hurst
ID: 41726853
Mostly today, numbers on a component have meaning. This is true for the stuff in my shop downstairs..
0
The Eight Noble Truths of Backup and Recovery

How can IT departments tackle the challenges of a Big Data world? This white paper provides a roadmap to success and helps companies ensure that all their data is safe and secure, no matter if it resides on-premise with physical or virtual machines or in the cloud.

 
LVL 12

Accepted Solution

by:
funwithdotnet earned 1000 total points
ID: 41726855
I forgot ... 510 = 51 ohms.
1
 
LVL 98

Assisted Solution

by:John Hurst
John Hurst earned 1000 total points
ID: 41726858
So then why is the "180" ohm resistor measuring 180 ohms. A given manufacturer would use the same numbering technique (which may not be standard).
1
 

Author Closing Comment

by:sidwelle
ID: 41726864
0
 
LVL 98

Expert Comment

by:John Hurst
ID: 41726872
Thanks. It is always the spec sheet that will tell you.
0

Featured Post

[Video] Oticon Case Study

Open office environments can create the dynamics for innovation, but they also bring some challenges. With over 1,000 employees in an open office, Oticon needed a solution that would preserve the environment while mitigating disruptive background noises.

Watch how they did it.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Arrow Electronics was searching for a KVM  (Keyboard/Video/Mouse) switch that could display on one single monitor the current status of all units being tested on the rack.
In this article, I’ll show how research, determination, and use of modern technology helped me solve a DNA mystery.
This video teaches viewers how to process images for a time-lapse video. Programs required: Adobe Lightroom, Adobe After Effects, Video Editing Program. In Adobe Lightroom: Import sequence image files into Adobe Lightroom: Develop settings of an I…
Sending a Secure fax is easy with eFax Corporate (http://www.enterprise.efax.com). First, just open a new email message. In the To field, type your recipient's fax number @efaxsend.com. You can even send a secure international fax — just include t…

661 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question