Bad Day At BlackRock

danatech

Member
Join Date
Mar 2004
Location
ohio
Posts
44
started off today one man short, due to one of the guys calling in sick. began, shortly after 6 a.m., installing buss plug and running approx. 250 ft. of 2 inch conduit to one of the new machines we recently acquired. had to pull off project several times during the day to handle "breakdowns". one, in particular, a recurring problem that we have tried to fix for over a week now. i finally decided to modify the program in the slc 5/04, to "streamline" the instructions and get rid of some un-needed redundancy. machine ran very well for the next few hours, (over 5000 cycles without a mishap), then crashed again with 2 new problems. in the meantime, after completing the 2 inch conduit run and getting set up to pull wire, (for second shift), the engineer in charge of the project told my supervisor, in an e-mail!, to hold off on running any conduit or air and hydraulic lines because the machine needed to be moved 32 inches, per a "revised" floor layout that nobody has seen! :(
my supervisor is in his second day of trying to quit smoking, so he was a lot grumpier and more stressed than he usually is. and he decided to unload on me and my crew today for the conduit debacle, the machine that won't "stay" fixed, and the tech. guy that had the nerve to call in sick!
before i left for the day, i told him i've been thinking about quitting smoking myself, but i was gonna wait till he mellowed out because we didn't need a war going on in maintenance with 2 grumpy old men at each other's throats!

sorry guys, been one of those days.... i just had to vent.


danatech (grouch)
 
danatech, You said:

one, in particular, a recurring problem that we have tried to fix for over a week now. i finally decided to modify the program in the slc 5/04, to "streamline" the instructions and get rid of some un-needed redundancy. machine ran very well for the next few hours, (over 5000 cycles without a mishap), then crashed again with 2 new problems.

It probably was not the program, was it? I bet you are wishing that you had never changed the 5/04. Some programs may have timers or counters that accumulate events over a long period of time, so 5000 successful cycles could be just luck...Maybe it wasn't unneeded redundancy.
 
the problem ended up being a bad output card. i replaced the card, reloaded the original program and the problems went away. (at least for now). good thing i saved the old program before i modified it, huh? :p
i just talked to the 2nd shift group leader and the machine is still running, (for almost 3 hours now.) at least i can relax now.

danatech
 
32 inches?
Whats wrong with that?
Lengthen it, shorten it, or put an elbow in.
With 250 ft of conduit, it is likely that 98% of it is in the correct location.
 
your absolutely right in that aspect, doug, but that's not the point. the machine was released to us yesterday to get power to, by the same jacka** engineer that said today to hold off on doing it. the machine has been sitting in one spot for almost two weeks. good thing i didn't have the night crew run the pipe and pull the wire last night. that engineer might be eatin' a lot of wasted material and manhours today. besides, i don't have the resources to keep doing something over and over because some desk jockey can't do his job or make up his mind in a timely fashion.
i guess 35 years of this is starting to wear me down,(at least a little). ;)



danatech (grouch)
 
There's a very, very, oooold adage in software programming...

Every subsequent software-fix ("patch") usually creates, at least, two, or more, damn-its.

Rules for Troubleshooting a long-running PLC program:

1. Check the field devices.
2. Check the I/O cards
3. Check wiring and comm-cables

If the program has been running reliably for some time and process operating conditions haven't changed (speeds, etc.), and the program hasn't been changed and then, all of a sudden, a problem shows up... the problem MUST be in one of those three areas.

The big caveat, however, is a change in the operating parameters.

If the process has been sped up above normal speeds (it happens all the time, don' cha know?)... then all kinds of timing issues are likely to come popping out of the woodwork.

I say this because, for most applications, most programmers develop rigid timers (static timer values) for particular circumstances. If speeds are increased then those particular rigid timers tend to become the source of many failures.

If that is the case, then the problematic static timer values need to be re-made into dynamic timer values.

The BEST advice that I can give to any programmer is to recognize that any process is more Event-Driven and Time-Driven, with a healthy "awareness of prior history", than it is Condition-Driven.

A Condition-Driven and Static-Timer-Driven control scheme will handle a lot of very simple processes... as long as they remain static and simple.

An Event-Driven and Dynamic-Timer-Driven control scheme (with historical references) will handle ALL processes... even if speed conditions change (within reason, of course).

The other major advantage to this scheme is that the program can detect when something unexpected happens, or it can ignore those conditions which it "knows" to be invalid.

A Dynamic-Timer is one where the Preset Value is calculated, at the appropriate time, and then loaded into the Timer before the Timer is activated. As speeds increase, timer preset values typically decrease. As speeds increase, one needs to watch for subsequent events sooner... Q.E.D.

(113)
 
Machinery moves

Boeing moved a machine from Wichita to Seattle. When they got it to Seattle they tried putting it into the pit. Found out the pit was 14 inches shallow. Fingers pointed, back stabbing, buck passing, blood ran galore. So they poured a 14 inch thick pad on the floor around the pit top.


Boss at school dist had me get ONLY enough wire (4 # 8s)for a 495 feet run. When I suggested a little extra he said I measured it - it s OK. SO I pulled it in. 3 feet shy. He was retired Marine top kick -- I learned a few new words that day. I bought more wire.

Dan Bentler
 
Thats funny. We once did this HUGE automation project where product was put into a dome. The dome was over 200' high, one guy died on it, and the job carried on. A large system of underground tunnels and conveyor belts took the dome's product (which I won't mention), and loaded it onto ships. What brought product to the dome? One large converyor.

After many months of contruction, the 'engineers' who designed the conveyor 'TALKED' with the 'engineers' who designed the dome.

The conveyor 'upper end' was to sit on top of the dome, and just drop product into it. 'Silly' dome was not designed to hold the weight of the conveyor.

Project: 'HAULTED'


Oh well, I still got to blow up things on top of a control tower. Barely made it out alive. Automation is good stuff.

Bill Bixby

[attachment]

darn.jpg
 
danatech said:
the machine has been sitting in one spot for almost two weeks.

Hell. You've got it made where you are. We would have had to had the conduit stubbed out before the machine made it to the plant and running the evening it showed up. Then we might come in the next day and move it 32 inches.
 
Danatech,
Breath deeply old friend. Every day that we wake up is a good day!
Some are just a little more uh...entertaining than others! I share your intense desire to twist a few necks during what I call "majors".If I read your post correctly you are running the production floor, overseeing the electrical installation, and playing go between the erectors and engineers, correct? Plus other duties that we are not aware of to be sure! Do you have a big red "S" painted on your chest? I am not sure if you are able to, but DELAGATE!
After smoking for thirty years I learned that there is never a good time to quit!
horned toad :D
 
danatech

If it were not for the
jacka** engineer... desk jockey
types, what would you have to bend conduit and pull wire for?

Sounds like a bad day. But, someone that 'fixes' a machine (albeit for 'a few' hours) by altering long-running code (removing 'unnecessary redundancy') instead of troubleshooting the failure should probably stick to running conduit. :D
 
lol! i knew that statement would get a "rise" outa somebody. ;) i happen to have a BSE also, as well as being the one who originally wrote the code for that machine. so, i claim the right to make changes, or do whatever it takes to get the machine up and running. and, because, even with all the professional qualifications i may have, i am human and do make mistakes from time to time. especially when pulled in several different directions, understaffed, with multiple requests and demands to prioritize "on the fly". perhaps, you'd like to trade jobs for a week? :D

danatech
 
After being there and done that before, I'd be willing to be that when all is said and done, you will look back with a sense of satisfaction with a job done. I would say well done, but in relocation instances with desk jockeys changing things and scheduling pressures, there are shortcuts to be made. Ok, we are all professionals here, I'll go ahead and say job well done.
 

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