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williamlweaver
User Rank
Platinum
Inventing a Solution...
williamlweaver   8/21/2012 5:55:46 AM
NO RATINGS
Thanks for a great (but scary) story, Cabe!  I noticed the Abort terminals are Labeled "+11" and "12 -". Did the contractors mistakenly think that these terminal name assignments were voltages? (+11 - 12 is a spread of 23). Gosh, this sounds like something I would have done. That is why the Engineers were always certain to keep the wires out of the hands of us Scientists. You should have seen them scramble when I approached a drill press...

naperlou
User Rank
Blogger
Experts!
naperlou   8/21/2012 9:08:43 AM
NO RATINGS
One thing you have to know about installers is that they are procedural people.  Often they don't follow the procedure.  Remember that collapse of a walkway, I think it was in Kansas City, in the 1980s.  It was a celebrated case.  The architects/engineers designed it properly, but the contractors did not follow the drawings. 

I worked at one company where we had complex machines that were installed by field engineers.  To ensure that this was done correctly without having to send out design engineers we started having the field engineers work with the development team during design and development.  This worked really well.  They knew why things were specificed the way they were.  Of course, some of the devices were in places like Hawaii and the northern coast of Germany.  The design engineers were always ready to go there.  Of course, one of the systems I worked on was going to Fort Hood in Texas.  That was always dangled as potential punishment (sort of like being sent to the Eastern Front in WWII Germany).

Charles Murray
User Rank
Blogger
Re: Experts!
Charles Murray   8/21/2012 9:39:20 PM
NO RATINGS
Naperlou, I think you hit it on the head here. The installers were procedural people. The other problem is that it sounds like they did a little shortcutting on the procedure.

rpcy
User Rank
Iron
Re: Experts!
rpcy   8/22/2012 9:49:16 AM
NO RATINGS
You're thinking of the Hyatt Regency walkway collapse in Kansas City MO, 1981. The original engineer's design was workable but marginal, calling for two suspended catwalks to be suspended from the same 40-ft threaded rods. When the builder got to that part of the construction, he balked at threading nuts and washers 20 feet onto each rod, so he made what he thought was a reasonable compromise: he'd use two 20 foot rods instead of one 40 foot rod. The top catwalk would hang from the ceiling, and the bottom catwalk would hang from the top catwalk. He ran this proposed change past the inspectors, the chief project engineer, and a few others, and they all approved the change. I use this example sometimes when talking to validation crews, because you don't have to know anything about civil engineering to realize that if the joints where the top catwalk transfers its load to the rod was workable in the original design, you now have two catwalks hanging from that stress point. Nobody seemed to realize this. And even at twice the weight, the joint held when first constructed. It was only when the catwalk was filled with holiday revelers that the joint finally failed, crashing the lower catwalk to the ground, and the upper one pancaking onto it. The contractor's original bonehead error managed to sneak by several other engineers and get approved. It is not clear that the original architect/engineer was ever consulted on this change -- you'd think that if anyone would have picked up on this gaffe, it would have been him/her.

TJ McDermott
User Rank
Blogger
Re: Experts!
TJ McDermott   8/24/2012 2:10:10 AM
NO RATINGS
RPCY, the original design wasn't even marginal; it was able to hold only 60% of the minimim load required by the city building code.  The bad choice for redesign meant the 4th floor structure would hold only 30% of the load required by the city building code.

The original design wasn't strong enough, required rediculous threaded lengths, and was poorly considered because the rods passed through the welded joint of two C-channels (making a rectangular tube).

The deformations of the 4th floor beams is just plain scary.

http://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse

There was plenty of blame to be shared by almost everyone for this.

Tool_maker
User Rank
Platinum
Re: Experts!
Tool_maker   9/17/2012 12:45:11 PM
NO RATINGS
There were two additonal factors not noted above: 1) In the construction, the two rods were offset in a common block instead of inline. Then the load was side thrust as well as tension pull. 2) The people on the catwalks were dancing. Therefore when keeping time with the music all dancers feet were impacting at one time which greatly increased the dynamic load. Anyone who has ever marched across a suspended bridge understands the meaning of this and knows why the Rout Step command was issued, Once the bridge was crossed evryone was again put in cadence.

TexasTJ
User Rank
Iron
Re: Experts!
TexasTJ   8/22/2012 1:30:03 PM
NO RATINGS
Interesting comment about Ft. Hood.  The last company I worked for got the contract for some expensive custom products (to protect the guilty, I won't say what) that were going onto some buildings that were being decomissioned.  I got the job to do the design work and enjoyed it.  But I had to demonstrate that  it would work before the Army Corps of Engineers would allow us to install.  While they were in our prototype lab, I asked what I thought was an innocent question, "Why were they installing this very expensive equipment on buildings that wouldn't be used."  They glared at me and said they had budget money to use up.

As an aside about the Army Corps of Engineers, I had found a substantial technical flaw in their standard bid document for our type of products.  I wrote a letter to Huntsville, AL (pre-email days) detailing the problem.  About a month later, I received a letter back stating that I was correct and they would update their documentation.  Eight years later, when I left the company, we were still getting the erroneous bid requests.

JimT@Future-Product-Innovations
User Rank
Blogger
Consider it an Investment....
JimT@Future-Product-Innovations   8/21/2012 1:17:21 PM
NO RATINGS
Comparatively speaking, I guess its like the Architect overseeing the Construction of a Building ---  you wouldn't be needed for the entire construction  project, but there must be some involvement beyond just handing over a rolled-up set of Blueprints. 

While I don't have experience in Buildings' electrical systems, I do have extensive history in designing electronic products and the associated duties of following the design into the manufacturing stage. 

Manufacturing a product always requires my complete supervision during the initial build and implementation.  Initially, On-Site (factory floor) Instructions;  then supervision; then a little hand-holding; until finally the crew was familiar and comfortable with all the design intents.  Without that necessary involvement (usually lasting anywhere from 1-5 weeks), success would always be jeopardized.  

Think of it as an investment in the processing of your design.  Plus the relationship you build with the people responsible will yield positive results in future design implementations.

campdavid
User Rank
Iron
BOTCHED CONSTRUCTION JOB
campdavid   8/22/2012 1:05:50 PM
NO RATINGS
THE FIRST THING I SUGGEST IS THAT YOU FIND OUT IF THE CONTRACTOR IA LICENSED AND CERTIFIED TO WORK ON FIRE ALARM/RELEASING PANELS. REQUIRED IN MOST STATES. A RANK BEGINNER SHOULD KNOW THAT ANY INPUT "ABORT" IS LOOKING FOR A CONTACT CLOSURE AND OPERATES IN THE MICRO OR MILIAMP REMGE. BY TIEING IT TO THE NOTIFICATION CIRCUIT YOU ARE DUMPING 1 AMP IN TO THE CIRCUIT. SO FAR AS INDICATED YOU HAVE BEEN LUCKY THAT THE ELECTRONICS HAVE NOT BEEN FRIED. FOR THE SAKE OF YOUR LIABILITY ON THIS PROJECT YOU SHOULD COMPLETELY TEST PANEL WHEN THE PROJECT IS DONE.

Thinking_J
User Rank
Platinum
Can not control (influence?) all the variables
Thinking_J   8/22/2012 4:52:29 PM
NO RATINGS
A Classic example...

You (your company) has control of everything going into a product. That is where the limit of your responsibility (should) end.

If that product requires other "professionals" to correctly install / operate it... you no longer have any direct control. And you should no longer have any responsibility.

Unfortunately, that isn't the way our legal system works.

Have numerous examples of similar screw ups by other "professionals" involved in installing/maintaining systems.

Education, certification of skills, etc.. will mitigate some of this. But it will not eliminate it.

 

William K.
User Rank
Platinum
Botched construction job.
William K.   8/22/2012 10:29:52 PM
NO RATINGS
My experiences with assorted contract installers have mostly been negative. Some of them got all of the connections correct but wasted huge amounts of wire, others have made errors in labeling wires, so that each end had a different number, one time a panelman skipped one terminal, and so half the wires were one terminal over from where they should have been. 

I have been fortunate that when it came to working on live systems I was able to do that myself, since I could move a bit slower and be more careful than the people eager to finish and leave for the next job.

Fire panels are unique in that they are indeed supervised, and that does add a requirement to accomodate the supervisory function. Mostly that calls for careful attention to polarities and diode directions, so it is not hard, but tedious.

rdelaplaza
User Rank
Silver
What about the LAW and depending HUMAN LIVES
rdelaplaza   9/12/2012 3:50:36 AM
NO RATINGS
All this regulations and licensing is worth... you name it.

This guys LICENSE should have been SUSPENDED immediately; their previous jobs INSPECTED for SAFETY. and recertification should have been a MUST for ALL responsible parties in that JOB.

HUMAN LIVES depend on this kind of SHODDY jobs.

That is why there are LAWS, REGULATIONS and INSPECTIONS, preventing Stupid, Lazy or Ignorant BOZOS from doing jobs where human lives are in DANGER. and PROTECTING the SAFETY of everyone.

ab3a
User Rank
Platinum
Finger Pointing 101
ab3a   9/12/2012 7:12:11 AM
NO RATINGS
I have worked on both sides of this problem, as both a field technician and as a registered professional engineer.

This problem cuts both ways. Experienced field installers know that there are some engineers who rarely get away from their cubicles. These installers don't have time to get in to a war of words with someone who doesn't know the situation on the ground; so they deviate from the design.

This is why we have "As-Built" Drawings.

Sometimes, however, the installer did not understand what the Engineer was asking for. It used to be that a phone call from the job site was expensive. Well, that's no longer true. I always recommend communications. If the installer didn't plan a few phone calls in the schedule for the work they bid, that's their own fault.

Tool_maker
User Rank
Platinum
Re: Finger Pointing 101
Tool_maker   9/17/2012 12:57:22 PM
NO RATINGS
I could not agree more. I used to build what I now design and have found both engineers and mechanics who are incapable of performing their assigned jobs if there is not someone there to hold their hands. The bigger the project or organization, the more likely these guys are to slip through the system and ride their way to retirement on other people's coat tails.

Fix-it-or-not
User Rank
Iron
Not surprised by this problem at all
Fix-it-or-not   8/16/2013 10:07:08 PM
NO RATINGS
I worked for a very large Fire Alarm company starting with E and anding in DS.  I was afyten involved in commissioning fire alarm systems that required me to test every circuit, and the action of every input and output device.  It gave me a very bad impression of the industry.

I had one job where the electrical contractor wired a thermostat across one of the detection loops!  This gave totally random alarms into the s might expect.  This was primarily because the contractor used cable from old jobs to do this job which totalled 40+ floors!  There was alarm rated cable, lumex (household wiring), BX, you name it, wired into the system.  The customer was thrilled, because the costs were low!  But it made for a very difficult time figuring out what was what.

I spent six months on that job, and with a week left to go, I was pulled away as the Senior Tech wanted to complete the job and get the glory, if there was any.  As I was leaving, I told him about the last problem that I knew of which consisted of the electrical contractor connecting the PAGING SPEAKERS to the STROBE LIGHTS.  As mentioned earlier, this just does not work!

Needless to say, about six weeks later I get a call from the Senior Tech as he could not resolve a problem with the supervisory system.  It seemed that every time the alarm went off, the supervisory system would indicate a ground fault.  I arrived on site shortly after and asked if this problem had been resolved.  I was told that none existed, so I pulled the PA speaker leads off the panel and connected them across the backup battery.  What do you know, the stobes started flashing!  The electrician knew immediately where the problem was, but refused to admit that it even existed when I was on the job.

It really doesn't matter who you hire to do a job, but you really need to look at the quality of the installation and the people doing the work.  I am going to appologise now before I make this statement, but I have found that the quality of alarm technicians, on average, is below competent.

I could go on and on about this, but I have said to much already.  Also, if you are in the contruction industry, do your due diligence and hire a competent engineering firm to commission your fire alarm system.  Most of the one that I worked with were incompetent and had no idea how the alarm systems did their job.  This amounted to a huige waste of time and money.

 

 

 

 

 

Fix-it-or-not
User Rank
Iron
Not surprised by this problem at all
Fix-it-or-not   8/16/2013 10:07:35 PM
NO RATINGS
I worked for a very large Fire Alarm company starting with E and anding in DS.  I was afyten involved in commissioning fire alarm systems that required me to test every circuit, and the action of every input and output device.  It gave me a very bad impression of the industry.

I had one job where the electrical contractor wired a thermostat across one of the detection loops!  This gave totally random alarms into the s might expect.  This was primarily because the contractor used cable from old jobs to do this job which totalled 40+ floors!  There was alarm rated cable, lumex (household wiring), BX, you name it, wired into the system.  The customer was thrilled, because the costs were low!  But it made for a very difficult time figuring out what was what.

I spent six months on that job, and with a week left to go, I was pulled away as the Senior Tech wanted to complete the job and get the glory, if there was any.  As I was leaving, I told him about the last problem that I knew of which consisted of the electrical contractor connecting the PAGING SPEAKERS to the STROBE LIGHTS.  As mentioned earlier, this just does not work!

Needless to say, about six weeks later I get a call from the Senior Tech as he could not resolve a problem with the supervisory system.  It seemed that every time the alarm went off, the supervisory system would indicate a ground fault.  I arrived on site shortly after and asked if this problem had been resolved.  I was told that none existed, so I pulled the PA speaker leads off the panel and connected them across the backup battery.  What do you know, the stobes started flashing!  The electrician knew immediately where the problem was, but refused to admit that it even existed when I was on the job.

It really doesn't matter who you hire to do a job, but you really need to look at the quality of the installation and the people doing the work.  I am going to appologise now before I make this statement, but I have found that the quality of alarm technicians, on average, is below competent.

I could go on and on about this, but I have said to much already.  Also, if you are in the contruction industry, do your due diligence and hire a competent engineering firm to commission your fire alarm system.  Most of the one that I worked with were incompetent and had no idea how the alarm systems did their job.  This amounted to a huige waste of time and money.

 

 

 

 

 



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