Big Error

[Peter Nachtwey]

This may match Pierre's disaster.

You know those boards that you put in your PLC? One time there was a programming 'glitch' in the environmental chamber that we use to test each and every board of a particular type. Instead of heating up to 70 degrees C it heated up to 220 degrees C. The result was 12 melted PLC motion modules. There was a lot of melted plastic and assorted surface mounted parts that slid off the boards as the solder melted. Picture that.

What can I do? I didn't do this, but it came out of my pocket.

Just be glad you had nothing to do with Chernobyl and no one died today.

 

[Fritz_frederix]

Hi there,

No one can beat Pierre, but a few years ago I received a little software to upload the software of an OP 17-panel of Siemens. The new series of Siemens where known that you only could download your software and never could upload it. So I had one OP-panel of which the back-up software was missing, the right opportunity to make that upload with the new software. With an OP-panel you got two options one option, the one I needed, is the set your OP ready for transfer and one option to delete the software in the OP.
It was friday afternoon and guess what option I chose. I can tell you when you shut down 1/5 of a plant you got some explanation to do.
Boy was I glad that I found the extual programmer which sended me a FREE copy on mondaymorning.

Think before you act and not only on a friday afternoon.

Rudi

 

[godfrey]

I removed a panel meter out of a wall in the control room of a wastewater facility to work on it. Somehow the power wires I removed were still live. They fell over and touched the back of the panel and arced. Five minutes later the operators were saying "I know we work in a sh*t plant but it really stinks in here". It was asweltering August day. Well, I had inadvertently killed power to a sludge press in the building. They eventually found the sludge press not running but sludge was continuing to pour out of the hopper and all over the floor. Well, I was in deep doodoo literally. They handed me a shovel. Yea, that taught me real good.

 

[Steve Etter]

A few years ago, I was in charge of a project to install 52 servo drives in a blending operation. All had gone well up until I and the maintenance supervisor did our I/O verification check. We happily went from one drive to the next checking every input and output. What we forgot was that the enable signal was a TTL input and that you can't just test it with a meter. In the end, we burned out 50 of the 52 drives. Had to pull them out and sent them back to the manufacturer to be repaired.

Fortunately for me, I was not personally responsible for the cost. I guess working for "the man" has its advantages.

Steve

 

[Goody]

The ‘KABOOM’ one made me laugh because a very similar one happened to me.

Me and my working partner were wiring and programming 8 ac drives.

The job was a great one; the drives were about 1m apart sat on top of a trunking fastened to a wall in a factory. We had a little production line going between us.

He was ahead of me fixing and wiring them and I was following connecting and programming the parameters. (the easy part for me)

He finished the last one leaving me to connect it up. He swears he told me – but I have no recollection of being told that the phase and motor wires on the last one were the wrong way round and I would have to cross them over.

Of course, I didn’t cross them over and I put the phase wires on the output side and visa versa.

Take a warning folks – ac drives don’t like it like that.

KABOOM is not the word; we had noise fire and smoke in an instant.

The profit in this job was about £1000 and guess what a new drive cost, yep a grand.
The blown up drive is somewhere in the back of my stores somewhere as spare parts. Hehehehehe.

 

[Eric Nelson]

Take a warning folks – ac drives don’t like it like that.

Yes, Goody, THAT connection scheme is especially damaging. So much that most drives specifically warn:
"Never connect the AC main circuit power supply directly to the AC drive output terminals!"...

Many of the drives I've used come with stickers attached in strategic locations so you don't forget. As I remove then, I (used to) think to myself "C'mon, I'm not THAT stupid!"...

The Kollmorgen drive had no stickers...

beerchug

-Eric

 

[stevez]

220 vac instead of 24vac

After receiving a new Datalogger after a long wait,I hurried to the workbench ,connected the power supply and ....BOOM.

I forgot to check what power supply I needed.Connected to 220vac instead of 24vac.

Another one-- 2 freeze dryers next to one another.
No. 1 empty.No. 2 in the midle of a 24 hour cycle.
Went to work on number 1.Turned keyswitch to manual...oops that was number 2 not number1 .


Mistakes will happen to all of us.(even the "professionals") .As long as no one gets hurt or killed ......its part of the job.

Phil,thanks for a great forum.

Steve

 

[ajbachhuber]

Who's insured?

I don't know any of you guys from a hole in the wall and except for those who have volunteered their professions, I don't know what most of you do. I was wondering if there are any consultants/self-employed techs who do contract/sub-contract work and specifically if any of you carry insurance either as a requirement or otherwise?

Some of you mentioned having to pay for your mistakes "out-of-pocket." Literally out of pocket? What if you managed to do hundreds of thousands of dollars in damage?

I know in the automotive manufacturing world we are held responsible if we stop a customer's production line because one (of millions) of the parts we made was not quite right. We are charged some rediculous amount of money for each MINUTE the line is down. I'm curious as to the level of liability you guys are open to.

-AJ-

 

[DickDV]

I probably should have some professional activity insurance but, I do so little hourly work where I feel at risk that I haven't done it yet.

Probably should!

Most of my consultant business is based either on application engineering (such as converting machines from DC to AC or Eddy Current Clutches to AC), project management (I alway require the customer to pick the contractors of their preference), and commissioning/startup service.

I've become used to managing risk over the years (maybe too much so) but I also watch carefully for vulture-type customers. These just might be the jobs the competition would be better off with! (In my view, of course!)

As always, collecting your bills presents some challenges too. If business conditions improve much this fall, I just may start charging a higher hourly rate for the slow payers.

 

[rsdoran]

Aint this sumthin, I got a job building panels

Now y'all done got me scared, or overly self concious which is just as bad. I make KABOOM all the time.

Can you believe I actually got hired to build panels and possibly be the programmer? Its kind of hard for me to believe.

I have only been working 2 days so far and overall its been kind of easy considering its in a type of steel plant, just rewired an air compressor with a panel off another air compressor and put some lock out mandrels on a panel. I have had to do a lot of walking but geez that kind of makes it even easier, the longer it takes to get parts/tools the less work you have to actually do, I expect that to change real soon though.

Life is good sometimes...no rent/house payment, decent job...what more can ya ask for?

 

[Terry Woods]

No... this probably won't "one-up" on Pierre's nor many of the other posted screw-ups... (What ARE you guys? Morons?... Don't flip out yet...)

When I was a young buck, learning the IN's-n-OUT's of being an Electrician, I had some time on my hands and so decided to go through some of "those" gutters... you know... the ones that require a Port-a-Power to close. I certainly believe in leaving enough wire to work with, what with modifications and various troubleshooting issues... but com'on... a Port-a-Power?

So... It's Saturday, this part of the plant was shutdown. I was going through those gutters... I had my "clamp-on" in-hand. So, I looked for the wires that weren't being used - that is, no current. I pulled the wires together and held them at the point where there would be no excess lead at all and then add a couple feet to each lead. I trimmed them back and tucked them in... uuummm, much better.

Then I moved on to trimming back the Neutrals. Hey! I doan need no stinkin clamp-on! Not with Neutrals! Neutrals ain't HOT no-how!

The first few neutrals that I worked on trimmed back nicely. Then...

Then, my luck ran out. My pair of strippers ended up 20-feet across the room. I had no idea where they went because I was too busy convulsing at the top of the step-ladder. I was "talking" to my long-dead Uncle John. He says... well, he gave me some good Stock Tips, which I ain't willing to share... at least, not yet.

On a personal level, that was the worst... that is, it could have affected me... in like, it really, really, personally, and physically could have affected me - like maybe dead or something like that.

I survived (being able to post at all proves it... doesn't it?... maybe not - I could be with my Uncle John with one hell of an ISP!) and then moved along merrily to all of the other potential disasters that living in this world affords.

Then there was this time that I programmed a Clutch and Brake to close... at the same time... together... know what I mean? Certainly I didn't mean to... but...

That little "ooops" shut down the Plant Production Line for over two hours. Fortunately... the Head Mechanic had MANY (did I only say MANY?... that should say, MANY, MANY, MANY) more "ooops' " than I did and he knew it. "Oh well, $hit happens", he says... with a big grin... as in, "Welcome to the Club, A$$hole!"

Then there was this really..... naaaahhhh... I ain't gonna bore you with any more of my human failings than I already have.

Bad Days? They're like Bananas... they come in bunches.

 

[The_Wanderer]

Bad Days? When do the good days start????

Recently we had a rather large machine being built in our shop for a potentially huge customer-- a conveyor line with 5 seperate stations. Supplied by the 3 phase power in our workshop, of course. By the way, whoever did the power wiring in our workshop should be shot if we can find him. After spending weeks with the machine working, getting tuned and fixed, I had to plug into a different power socket one day. Turns out the Neutral was not attached to this socket. About a second after pluggin in, I heard not one big Kaboom, but something like popcorn in the micorwave. When I saw the smoke coming out of the PC monitor, I rather quickly hit the isolator. Nothing tooooo bad, just a PC monitor, a Panelview 600, an inverter, a few MCB's, a contactor or 2, and a few days work... Oh, and the customer came in the next day to "check on Progress". Oops!

 

[smersh]

About 8 years ago when starting out, I was working on a sewage works.
One of the mains only had a capacity to drain 1 sludge tank at a time
(there where 6). Unfortunately, I screwed the code and opened 3 tanks up. The mains went right through the centre of the site - there was an inspection chamber etc. Well you know the expression , knee deep in sh*t. Took about six days for the flies to eat it all up!

 

[Tom Jenkins]

I could go on and on and on ........

My personal biggest was snapping a 4" coupling and trashing a 700 hp blower when the motor came back on across the line and the blower rotating at full 3,600 rpm when I released the momentary E-Stop. Seems that my expectetation of the how the starter was wired didn't match GE's, and ......

Ever since I use push to stop twist to release E-Stops!

(For my co-workers in the wasewater treatment field: you can't be in this business very long without taking a $hit shower - literally AND figuratively!)

 

[Fritz_frederix]

Tom,

Is it possible tht I smell you? lol

Rudi