HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
  |  REGISTER  |  LOGIN  |  HELP
<<  <  Page 2/2
William K.
User Rank
Platinum
Re: But are the functions really separate?
William K.   1/24/2014 3:00:46 PM
NO RATINGS
I know that they are saying that, but I have not heard any explanation of facts that would validate the claim. It is one thing to make an assertion and a somewhat different thing to be able to explain in detailwhy it is true. My feeling is that they have not covered all of the failure modes that I have seen. So if they would like to place a really detailed article in Design News about the actual mechanism of why their combined system is safer I would certainly be happy to read it.

Rob Spiegel
User Rank
Blogger
Re: But are the functions really separate?
Rob Spiegel   1/24/2014 10:21:35 AM
NO RATINGS
You're not alone with this skepticism, William K. Certainly for years it was unheard of to combine both functions on the same network. But the safety folks are saying these combined networks are safer than the old single-duty safety networks.

William K.
User Rank
Platinum
But are the functions really separate?
William K.   1/24/2014 9:46:45 AM
NO RATINGS
I keep seeing the claims that somehow safety functions and control functions all using the same processor can offer complete separation and 100% reliability. Of course there are a few hardware parts that are common to both of them and it is a challenge to imagine that if excessive enclosure temperature causes one part of the processor to lock up that the other part will continue to function as it should. And a power supply failure would probably shut the whole package down, as well. So while automation has become simpler and less expensive it does not make sense to go to those extremes of combining everything, even if it does reduce the initial prices.

<<  <  Page 2/2


Partner Zone
Latest Analysis
A bold, gold, open-air coupe may not be the ticket to automotive nirvana for every consumer, but Lexus’ LF-C2 concept car certainly turned heads at the recent Los Angeles Auto Show. What’s more, it may provide a glimpse of the luxury automaker’s future.
Perhaps you didn't know that there are a variety of classes, both live and archived, offered via the Design News Continuing Education Center (CEC) sponsored by Digi-Key? The best part – they are free!
Engineer comic Don McMillan explains the fun engineers have with team-building exercises. Can you relate?
The complexity of diesel engines means optimizing their performance requires a large amount of experimentation. Computational fluid dynamics (CFD) is a very useful and intuitive tool in this, and cold flow analysis using CFD is an ideal approach to study the flow characteristics without going into the details of chemical reactions occurring during the combustion.
The damage to Sony from the cyber attack seems to have been heightened by failure to follow two basic security rules.
More:Blogs|News
Design News Webinar Series
12/11/2014 8:00 a.m. California / 11:00 a.m. New York
12/10/2014 8:00 a.m. California / 11:00 a.m. New York
11/19/2014 11:00 a.m. California / 2:00 p.m. New York
11/6/2014 11:00 a.m. California / 2:00 p.m. New York
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Jan 12 - 16, Programmable Logic - How do they do that?
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  67


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Copyright © 2014 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service