HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
  |  REGISTER  |  LOGIN  |  HELP
Blogs
Sherlock Ohms

These Fuses Melt in Water

NO RATINGS
Page 1 / 2 Next >
View Comments: Threaded|Newest First|Oldest First
Beth Stackpole
User Rank
Blogger
Averting a major problem
Beth Stackpole   10/15/2012 8:08:35 AM
NO RATINGS
Water and electricity--not a good combination. Nice detective work and good thing you resolved the problem in fairly short order. Seems like it was a recipe for a far more dangerous situation.

naperlou
User Rank
Blogger
Re: Averting a major problem
naperlou   10/15/2012 9:26:37 AM
NO RATINGS
Beth, as you note, it was a potentially dangerous situation.  It could also have been expensive for the Air Force.  That equipment is very expensive and complex.  Finding issues with it would have been costly.

It is interesting how construction problems come up in almost any project.  Even though the contractors work to code, there are often problems like those discussed here.  Perhaps there needs to be some sort of acceptance testing defined.

Charles Murray
User Rank
Blogger
Re: Averting a major problem
Charles Murray   10/15/2012 10:30:05 PM
NO RATINGS
I agree, Beth. It's great detective work. I'm repeatedly amazed at how resourceful are Sherlock Ohms authors are when it comes to tracking down very odd problems like this one.   

Rob Spiegel
User Rank
Blogger
Re: Averting a major problem
Rob Spiegel   10/15/2012 11:40:50 PM
NO RATINGS
I agree, Chuck. It's surprising how these Sherlock Ohms bloggers track down their problems. Time after time, they seek out both the obvious and the completely obscure. 

daveladd
User Rank
Iron
Re: Averting a major problem
daveladd   10/22/2012 3:27:44 PM
NO RATINGS
Every electrical shop ought to have an infrared camera.  You can get a reasonably good basic model these days for 6-800$  When you have unexplained fuse and circuit issues, scan the panel, the receptacles, starters, etc.  For troubleshooting, where you have quirkly stuff going on, it's much safer to start with the IR scan than to go poking around on fuse clips with meter probes, looking for voltage drop, or manipulating conductors to get a clamp-on ammeter attached.  You're liable to poke a connection that's loose and start an arc that results in an arcing fault ... in your face. 

Larry M
User Rank
Platinum
Re: Averting a major problem
Larry M   10/22/2012 3:36:40 PM
NO RATINGS
Daveladd wrote "Every electrical shop ought to have an infrared camera.  You can get a reasonably good basic model these days for 6-800$."

You don't even need to buy a special infrared camera. The image sensors in inexpensive point-and-shoot cameras and even cellphone cameras are sensitive to infrared and the cameras have no filters. You can quickly find a hotspot just by waving the camera around. (The camera is also a good tool to check your TV or DVD player remote. Watch the camera screen while pressing buttons on the remote.)

You can measure the hotspot temperature with one of these inexpensive non-contact devices" http://www.harborfreight.com/catalogsearch/result?q=thermometer . They are also useful for measuring duct outlet temperatures when you suspect heating or air-conditioning problems.

 

 

tekochip
User Rank
Platinum
Re: Averting a major problem
tekochip   10/22/2012 6:47:26 PM
NO RATINGS
$30 for an ir thermometer? Crazy, but I have to try that camera trick. I've used cameras to pick up remote signals before and is helpful when focusing IR sensors.

curious_device
User Rank
Gold
Re: Averting a major problem
curious_device   10/22/2012 11:56:50 PM
NO RATINGS
I can absolutley second the PIR thermometer sweep of high power systems.  I have found truly shocking faults that were well on their way to a disaster.

Larry M
User Rank
Platinum
Re: Averting a major problem
Larry M   10/23/2012 10:24:31 AM
NO RATINGS
tekochip wrote "$30 for an ir thermometer?"

I've used the $15 ones with great success.  In fact, when they were on sale for $10, I bought a few for my sons and friends. The major difference is that they don't have the targeting laser--you actually have to pay attention to where you aim them.

I used one of them to determine why CFL lamps were failing after only a few months in my ceiling fan wihich has they typical base-up mounts with small shades.

30 seconds after turning the lamp on from a day at 70-degree room temperature the lamp base was at 155 degrees F. Question answered.

warren@fourward.com
User Rank
Platinum
Re: Averting a major problem
warren@fourward.com   10/22/2012 3:42:41 PM
NO RATINGS
It is amazing how often the simple things are often overlooked. Fuses aren't as complex as the equipment they are protecting, so we find it easy to dismiss them. The same way with plugs, knobs, pots, switches, and other interim devices.  We forget they are there until we have problems we cannot explain.  He did a good job finding the problem!

TJ McDermott
User Rank
Blogger
We talked about fuse substitution last month
TJ McDermott   10/15/2012 12:58:37 PM
NO RATINGS
In this article, a maintenance technician improperly replaced a 50 amp fuse with a 60 amp fuse.  Our discussions last month said this should never happen, and yet it does, time and again in the real world.

Sometimes it's poor design and the rated fuse is truly undersized.  Most times, the fuse it telling us there is something abnormal that must be fixed, and yet the single most common troubleshooting procedure is to replace the fuse to see what happens.

Fuses may be doing circuit protection a disservice by looking so innocuous.  The fuse manufacturers might consider making them more impressive, more imposing, in order to gain some respect.  Maybe the fuses need literal bells and whistles to tell us there is a significant problem.

Beth Stackpole
User Rank
Blogger
Re: We talked about fuse substitution last month
Beth Stackpole   10/16/2012 7:06:14 AM
NO RATINGS
Interesting point, TJ, that it's the natural inclination to sidestep what the fuse might actually be trying to indicate with its behavior for a fix that is initially finds the fuse at fault and subs it out. As a parallel, I do that repeatedly when my smoke detector shrills--I take out the battery and reset the device and don't give any kind of real consideration to the fact that there might be a problem. Call it the lazy person's guide to troubleshooting.

Beth Stackpole
User Rank
Blogger
Re: We talked about fuse substitution last month
Beth Stackpole   10/16/2012 7:07:00 AM
NO RATINGS
Interesting point, TJ, that it's the natural inclination to sidestep what the fuse might actually be trying to indicate with its behavior for a fix that is initially finds the fuse at fault and subs it out. As a parallel, I do that repeatedly when my smoke detector shrills--I take out the battery and reset the device and don't give any kind of real consideration to the fact that there might be a problem. Call it the lazy person's guide to troubleshooting.

deejayh
User Rank
Silver
Re: We talked about fuse substitution last month
deejayh   10/16/2012 10:00:11 AM
NO RATINGS
Just raise the price of the fuses to something intolerable.  Management won't tolerate that too long.  When the box costs less than the fuses they'll agree more quickly to replacing it.

TJ McDermott
User Rank
Blogger
Re: We talked about fuse substitution last month
TJ McDermott   10/16/2012 10:10:36 AM
NO RATINGS
 

Now that's a good idea.

On a recent troubleshooting call, the fuses in question were rated for 650 amps.  The customer had a "water event" through their motor control center.  After replacing the fuses and powering up, they blew a second time.  Since these 650A fuses cost $350 a piece, blowing 3 of them a second time was expensive enough to justify calling in some expert help.

Still, to justify the very high cost you propose, some bells and whistles would be appropriate.  

Tool_maker
User Rank
Platinum
Re: We talked about fuse substitution last month
Tool_maker   10/24/2012 12:36:43 PM
NO RATINGS
  I am not an electrical engineer, but I think I know how fuses work. Can you explain why any fuse would cost $350? Even if they are only produced in small quantities that sound outrageous. I have quoted supplying components for a large supplier of fuses who is headquartered in this area and I have never been successful. They throw pennies around like sewer lids.

tekochip
User Rank
Platinum
Hot Contacts
tekochip   10/15/2012 4:48:37 PM
NO RATINGS
I've seen the problem with overheating fuses before.  In my case it was a consumer device with rather cheap fuse clips rather than an actual holder.  Contact resistance is something that is frequently overlooked, and it shouldn't be.  The worst I had was a coffee maker with a bad Faston crimp.  The contact became so hot that it burned a hole in the circuit board and started a small kitchen fire.


Larry M
User Rank
Platinum
Re: Hot Contacts
Larry M   10/22/2012 3:41:56 PM
NO RATINGS
My dishwasher has a small circuit board with user option switches on it, connected with a Molex connector. One of the switches is directly in series with the heating element used for drying. The Molex connector also caused a circuit board fire.

I suppose I could submit this as another Made by Monkeys article but I've just told the complete story (except for the repair).

pennyman
User Rank
Iron
Melting fuses
pennyman   10/16/2012 9:41:39 AM
NO RATINGS
I used to repair coin operated games for a living - I had several issues with fuses melting instead of blowing. Usually, replacing the fuse holder solved the problem - until I came across Pole Position and Pole Position II. Both these games had a 3ag(agc) fuse rated at 20 amps for the main +5v power supply rectifier. After the games hit the 5 year mark, they started melting fuses. Changing the fuse holder didn't solve it, neither did removing the crimp on connectors to the fuse holder and soldering the wires directly to the holder. The solution was to take 2 AGC fuse holders and wire them in parallel and install 20 amp fuses. The load draw from the game was causing an ultrasonic vibration that was causing the solder to run out the end of the fuse. The telltale signs were the blob of solder out of the end of the fuse, and the fact that when it was running, the fuse was cool to the touch. After the modification, the fuses never failed in that manner.

OLD_CURMUDGEON
User Rank
Platinum
OOOOPS!!
OLD_CURMUDGEON   10/16/2012 9:47:36 AM
NO RATINGS
I see several comments here which are worthy of my 2 cents.

It was interesting to read the part about this fellow having to "consult" with three or more "CE" personnel BEFORE getting the requisite repair.  Sounds like TYPICAL gov't operation, OR maybe a CYA move!

My uncle was an electrical contractor with many certified electricians & helpers running large & small jobs.  When in college I also worked for him during the summers & other times off.  Furthermore, I have had close friends who are or were in the commercial/industrial/residential electrical contracting field.  It has been the topic of conversation MORE than once over the years as to the "effectiveness" of the local Bldg. Dept. inspector.  The runningjoke is whether the inspector actually gets out of his vehicle or not, before, during and/or after his report is filed.  So, while the purist may call for more diligent authenticating processes, in the real world this ain't never gonna happen!!!!  People are people, and soon learn how to flim-flam their jobs, especially in local gov't services.

So, while it may be altruistic to assume that a licensed contractor WILL do the proper thing in a project, there's MORE evidence to substantiate the fact that either the foreman or the laborers will take steps to short circuit (no pun intended!) that effort.

As a current example, the "kids" just bought a new house.  It was a pre-owned house about 6 years old.  The lending bank required a home inspection by a registered engineer.  His report included the fact that in one of the bedrooms the A/C ducts were improperly connected.  I asked myself, "how can this be?"  So, I set the thermostat to energize the system, scaled a ladder (9 feet ceilings), and felt the air.  It was cool to the sense.  Additionally, this room has a filtered return duct.  I went to it, and felt the return air motion.  Where's the problem?  I couldn't find one.  Additionally, the mandatory line-voltage-powered fire alarms chirped, all of them.  Installing new 9-volt batteries did not help.  Where was that in his report?  It turns out that there was a defective unit causing the others to broadcast a chirp signal.  Finally, each bedroom ceiling is equipped w/ a circuit box for mounting a fan and/or fan-light device.  The box is wired with a piece of 3-wire Romex (Blk, Wh, R), and there are two wall switches.  So, one would expect that one switch controls the Blk circuit, the other switch controls the Red circuit.  NO!  The Red switch controls one receptacle of a duplex receptacle on one of the bedroom walls.  Where is the other end of the Red wire in the ceiling box?  Who knows, but it's powerless, and tucked into the box.  How did these serious deficiencies pass "inspection"?????????  I rest my case!

 

rkinner
User Rank
Iron
Re: OOOOPS!!
rkinner   10/22/2012 5:27:24 PM
NO RATINGS
I also had an "issue" with a new construction house I moved into 10 years ago. First, I had my own inspector do an onceover on the house and found that the range wiring had a high impedance to ground on one phase. The problem was that the drywall had been installed with a nail that was put entirely through the phase wire. The builder was not happy but replaced the entire feed and redid the drywall.

About 6 months later i installed a ceiling fan in our dining room and tried to control it from the switch that had been prewired by the builder. No power anywhere downstream of the switch (but the switch had 120 VAC on it)! After much up and down on the ladder, I pulled the wiring out of the box at the switch and found that the wire I used had some electrical tape wrapped around it. It ended up that the wire had been cut and since it was not immediately put in use the electrician simply hid it by wrapping tape around it.  It did pass inspection but wasn't usable.  I did get enough wire freed up to make the connection and got the switch operational but not before a few choice words about a fellow in my profession.

 

OLD_CURMUDGEON
User Rank
Platinum
Re: OOOOPS!!
OLD_CURMUDGEON   10/23/2012 7:52:55 AM
NO RATINGS
Well, IF I could have done a rewiring job for the ceiling fan outlets, I certainly would have, but we are talking about a FLORIDA house, so the outer walls are concrete block, the ceilings are 9feet tall & the floorplan is THE MOST OBTUSE I've ever seen.  This house is an example of "free-thinking" design, and as such the layout is anything but sensible and/or convenient.  Additionally , there is virtually no access to the attic space, so running new cabling is next to impossible.

To add insult to injury, when I casually mentioned this dilemma to a LOWES' floor person in the Electrical Dept., he gave me a "cannot be" lecture, at which point I reminded him that I am a graduate electrical engineer w/ 50 years practical experience in electrical & electronic processes.

For a house of this footprint dimensions, the wasted space is almost enough to make a second house, but the "kids" like it, and since THEY have to live there, so be it!

I have one more bedroom ceiling fan to install correctly, so when I check this circuit out, I'm going to look very closely (AGAIN!) at the switchbox on the wall to ensure that there is NO "red" wire in the box.  My suspicion is that the fellow(s) on the job may have run out of wire, but had some 14-3 on the truck, and so ran it from the switchbox to the ceiling box, and since they weren't supposed to provide a two-switch circuit, may have cut off the red wire @ the switch box, making it unavailable for use.

Critic
User Rank
Platinum
Re: OOOOPS!!
Critic   10/23/2012 10:22:40 AM
NO RATINGS
I am pretty sure that having extra ("spare") un-energized conductors present in home wiring is not a code violation, and wouldn't prevent a wiring job from passing inspection.  Perhaps our colleagues who are more knowledgeable regarding the NEC can comment on this.  I do agree, however, that poor workmanship (and poor design) is prevalent in home wiring.  If you want something done right, do it yourself!

OLD_CURMUDGEON
User Rank
Platinum
Re: OOOOPS!!
OLD_CURMUDGEON   10/23/2012 12:15:28 PM
NO RATINGS
There's NO question about the legitimacy of including extra (unenergized) circuit wires in a raceway.  However, in THIS case, this is NOT the situation.  I believe the problem may be traced back to the condition that I described above.  When I peered into the 2-gange switch box on the wall, there is only one cable w/ a 3-wire configuration, and that cable goes to a receptacle on the wall.  One part of that duplex receptacle is live all the time, the other is connected to the red wire, which allows the convenience to be able to switch a table lamp or bedside lamp as one enters / leaves the room.  The other switch in the box is wired to a cable that goes to the ceiling box for a light and/or fan device.  This cable has NO red wire showing at the switchbox terminus, BUT there IS an unenergized red wire in the ceiling box.  I will look more closely to determine IF the other end of this red wire has been cut as it enters the switch box.  Wouldn't surprise me one bit.  I've seen some very weird and unacceptable constructs in my lengthy career.

An inspector WOULD NOT take notice of a minute detail such as this, and once the house was "walled in", it would be too late to rectify this problem.  Unfortunately, in this case, the house was rented for about 4 years from the time it was first built.  And, with a 2-year empty status due to a foreclosure, the problem was not discovered until now, and now it's too late to seek any remediation from the original parties involved.

bob from maine
User Rank
Platinum
Troubleshooting AC
bob from maine   10/16/2012 10:36:11 AM
NO RATINGS
The replacement of the fuse with one of a higher rating while going to the parts room for the correct value makes sense. The clamp-on ammeter showed much less current flow than the fuse rating. It is a military installation so the presumption is it MUST stay operational and it will be staffed while the electrician is en-route. No equipment had malfunctioned, so it could be assumed (love that word!) that the problem was in the wiring. Blowing a 40A fuse on one leg of a 208 3PH line implies a heck of a lot of heat being dissipated somewhere. All these being considered, upping the fuse and going for more fuses seemed the reasonable thing. Picking up the blown fuse was pure luck. Understanding what the temperature of the fuse implied was the stroke of genius. Those fuses are removed using pullers and there would normally be no reason to handle the fuse with your bare hands. Good story and a good lesson for the rest of us: be curious, observe, think.

Jon Titus
User Rank
Blogger
Similar problem
Jon Titus   10/16/2012 12:51:56 PM
NO RATINGS
We had a similar problem in our first house--water in the circuit-breaker box.  I looked for a leaking water line but found none.  Then during a rain storm I noticed water dripping from the breaker box.  Apparently water got into the outdoor service cable, ran into the meter box, and then the water flowed into the service cable and into the breaker box.  The local power company came and wrapped their part of the cable in waterproof tape.  Then I thoroughly caulked the meter box with silicone sealant.  No more water problems.  The circuit-breaker box was about 20 feet from the entrance of the service cable into the house, so a lot of water had to accumulate to push through to the circuit breakers. No permanent damage, thankfully.

Irwin@DigiKeyEdu
User Rank
Iron
Nick in Cable
Irwin@DigiKeyEdu   10/23/2012 9:29:35 AM
NO RATINGS
One time I couldn't access my workstation with username and password using the enter key on keyboard. So I tried a whole lot of times of accessing and than onetime instead of using keyboard enter key I used the mouse and clicked the ok button and than I was able to login. So I logged out and tried the keyboard enter key and noticed that when I pressed the enter key another character was being added to the password when I pressed the enter key. So tried the mouse again and I was able to login. Logout and tried the keyboard enter key and again the added character was added to password.

So, I did a process of elimination of sequences and used the rule number one, always check you're connection first. So, I unplugged the keyboard cable and looked at it real good and noticed the cable had a small little nick in the cable. Than I looked, how the nick was caused and what was happening to the cable during normal usage. What I discovered was, the keyboard sat on a keyboard-sliding tray and when the keyboard tray was pushed in the cable would get caught between the sliding part and this must of cause the nick in the cable.

But the darness thing about the whole thing was the extra character that was added to the password when I would press the enter key and back tracing my sequences.

Irwin@DigiKeyEdu
User Rank
Iron
A Bug between a Relay
Irwin@DigiKeyEdu   10/23/2012 10:09:29 AM
NO RATINGS
This summer I added a DCU to an AC Compressor outside. The DCU has conservation cycles to prevent brownout for electric grid. The DCU has no ok status led only a running status led when it is doing a cycle. The inside of house started to get hot one day and by second day I noticed that I should check the system. So, I lowered the thermostat to make a call to air handler. The thermostat status would show running so I though the issue wasn't the thermostat. Next, I checked the air handler and noticed that during the thermostat run cycle was enabled that the air handler would run. So, I though, okay it's not the thermostat or air handler and the issue had to be outside and the DCU was causing the request from air handler to be denied to compressor because there was no okay status light running or test or reset switches.

So, I called the electric company and a technician came out and checked the DCU. We doubled checked the breakers, ohm checked fuses to compressor and the electric to compressor. Everything was checking out a-okay. Now there was only one more thing to check which was the DCU low voltage signals to a relay switch for the high voltage and noticed that the relay wasn't making the contact.

So, the technician looked real hard with flashlight at the contacts of relay and noticed something was between the relay contacts. It was a little bug about half inch long stuck between the relay contacts. Throughout the years I have noticed a whole lot of issues that arise out of relays. However, that little bug knocked the whole system down. It reminds me of the myth from IBM's first relay computer story about bugs in the system. This is where the term bugs in your system comes from.

OLD_CURMUDGEON
User Rank
Platinum
Re: A Bug between a Relay
OLD_CURMUDGEON   10/23/2012 12:05:42 PM
NO RATINGS
The "myth" about bugs in a computer is NOT a myth.  But, that is where the term originated.  When the first ENIAC was fired up about 1948, there were thousands of relays used as memory cells.  A moth had gotten itself swept up into the guts of the computer, causing one of the relays to not make when it was supposed to.  After much troubleshooting, the moth was discovered & removed.  The ENIAC continued to calculate.  Dr. Hopper of the U.S. Navy was part of that event in history.

mr_bandit
User Rank
Iron
Re: A Bug between a Relay
mr_bandit   10/25/2012 10:00:39 PM
NO RATINGS
Actually, the term "bug" came from telephony, as in "sounds like bugs on the wire". I suspect early telephone equipment were also invaded by bugs, but that is just a guess. Steven Levy's book Hackers goes into this a bit, IIRC.

She found the moth in a relay (relay #70, panel F), and taped it into her log book with the note "First actual case of bug being found". The logbook page is in the Smithsonian.

 

google "Grace Hopper bug" for pictures of the page (92) and the moth. Date was 9/9, 1947. One good source:

http://www.anomalies-unlimited.com/Science/Grace%20Hooper.html

 

 

GuidoBee
User Rank
Iron
Re: A Bug between a Relay
GuidoBee   11/1/2012 7:14:34 PM
NO RATINGS
the link at the bottom of mr bandit's post can be inspirational to those folks who don't want to be told what they cannot do.  Adm Grace Murray Hopper is one of my heroes (heroine?).  Just to add a bit to the linked info, Adm Hopper was interviewed on 60 minutes, was a regular on the lecture circuits (no pun intended) and is the namesake of the Computing center building at the Naval Air Station at North Island (San Diego), CA in addition to the (Navy) combatant ship named after her. 

I think she serves as a great example to anyone considering a career in technologies or computers, but especially for young ladies and girls who wonder if they can become leaders in high tech areas (may not be so much doubt about that now), but it was the likes of Amazing Grace who led the way 65  years ago. 

CDR, USN, RET

skyefire
User Rank
Gold
Re: A Bug between a Relay
skyefire   10/29/2012 1:17:27 PM
NO RATINGS
Never had a *bug* in my AC unit, but I did have a relay in the outdoor compressor unit fail several times.  The relay was an unsealed, open type, which was located near the bottom of the unit.  Since the housing of the unit was open at the bottom, the relay was (mostly) protected from rain, but any time we had to mow the grass or weed-whack the growth around the compressor, clippings would be driven with enough force to "hook" up under the lip of the housing and hit the relay, carrying enough moisture to eventually cause corrosion.  Ditto for snow during the winter.  The first time that relay failed, it jammed *closed*, and kept the compressor running constantly for *weeks*.  We didn't notice b/c the compressor was a quiet type, and the central air blower inside the house only activated when the thermostat ordered it (and I was working very long hours).  I first noticed something odd when i had to enter the crawlspace and found the high-pressure coolant line was dripping condensation over its entire length constantly, even when the central air wasn't running.  Ended up tracking down the culprit by killing the thermostat power circuit and realizing that the compressor kept running.  The relay was only $20, and I replaced it myself easily enough, but good grief, the electric bill for that month was ENORMOUS.

That relay became the "first check" item whenever there was an AC problem for the next several years.  It never jammed closed again, but it did fail a few more times. Why anyone would use a relay with mechanical components open to the elements in an installation like that is beyond me.

Partner Zone
More Blogs from Sherlock Ohms
Sherlock Ohms highlights stories told by engineers who have used their deductive reasoning and technical prowess to troubleshoot and solve the most perplexing engineering mysteries.
Sherlock Ohms highlights stories told by engineers who have used their deductive reasoning and technical prowess to troubleshoot and solve the most perplexing engineering mysteries.
Sherlock Ohms highlights stories told by engineers who have used their deductive reasoning and technical prowess to troubleshoot and solve the most perplexing engineering mysteries.
Sherlock Ohms highlights stories told by engineers who have used their deductive reasoning and technical prowess to troubleshoot and solve the most perplexing engineering mysteries.
Sherlock Ohms highlights stories told by engineers who have used their deductive reasoning and technical prowess to troubleshoot and solve the most perplexing engineering mysteries.
Design News Webinar Series
9/25/2014 11:00 a.m. California / 2:00 p.m. New York
9/10/2014 11:00 a.m. California / 2:00 p.m. New York
7/23/2014 11:00 a.m. California / 2:00 p.m. New York
7/17/2014 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.
Oct 20 - 24, How to Design & Build an Embedded Web Server: An Embedded TCP/IP Tutorial
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  6


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.
Next Class: September 30 - October 2
Sponsored by Altera
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