OT: So Much For a Quiet Sunday

[ASF]

Jenkins Law: The technology least understood will always be blamed for any problem.

Gee Tom, I always thought that was Bailey's law.

I think this one is universal enough that we should just call it "SI's Law"

 

[bitmonkey]

op: This grid checker is messed up again.
me: How so?
op: It's showing the plates are bad.
me: (after checking the hi and lo limits that operator typed in) Well, they are bad. That's what it's here for, to show you when you have bad plates.
op: That thing is a piece of s***!

 

[jgreenewv]

Angry customer calls: "One of our water tanks stopped working on the SCADA system. You've got to come fix it right now!"

Drive to the site, lift the vault lid (because the electronics should ALWAYS be installed in the most damp location possible) to find the vault full to the top of water. Call the customer to report, he doesn't believe me, and drives out to the tank. Yep, full of water.

"But my operators check this every day!"

I think your operators might be misreporting.

 

[FactoryTalktotheHand]

"But my operators check this every day!"

You gotta love a manager that actually believes anything an operator says.

 

[FactoryTalktotheHand]

Got lots of that when I was in maintenance. Especially this one meat pump. It was fairly complicated: a dual-piston pump with a switcher valve in the front, all run by a SLC 5/02. 99% of the time, the problem was either hydraulic or one of the prox switches by the front valve. 100% of the time they'd call me down because "there's something wrong with the program."

 

[labeledas]

My favorite

On a site that had been operational for 5 years with no issue

Operator: get out here this stupid program started acting up. Whenever I run pump1 in lead pump 2 runs as well even a low flow.
Me: what does it do with pump2 in lead
Operator: everything runs fine.
Me: pump 1 is not producing enough pressure.
Operator: no pump is fine it's the stupid f#$@ing program get out here.

2 hour drive later
Disable pump2 run pump1 look super low pressure produced even when deadheaded

Operator: has to be the program slowing it down
Me: it's a full voltage starter your pump is faulty.

Operator: must be an electrical issue

This went on for about 3 hours I had to pull apart everything until the operator figured out the pump was shot

 

[Ken Roach]

"The VFD is faulty, we keep getting an overtemperature fault and it won't run the conveyor."

"Have you checked the coupling and the drivetrain to see if they're binding up ? What's the measured temperature at the motor ?"

"There's nothing wrong with the mechanics. It just won't start the conveyor. We've tried everything, get over here !"

[Drives to customer site, an aggregate/concrete plant]

"Okay, let's start by decoupling the motor from the load. Show me where the conveyor is."

"It's right over here on this gravel conveyor. We told you there's nothing wrong with the motor."

"Which conveyor ?"

"Over there, right under the truck dump."

Under the truck dump was a twenty-foot pile of gravel.

Under the pile of gravel was the motor, the coupling, and the drive sprocket.

 

[willxfmr]

Op: You have to change the vacuum sensor.

Me: Why do you think it's bad?

Op: I keep getting a low vacuum fault.

Me: Have you checked the filter on the vacuum generator?

Op: There's a filter?


Every fault here should say "Sensor failed", because every air, water, temperature, pressure, or flow fault is thought to be caused by a failed sensor. And if it's not a failed sensor, then clearly it MUST be a program glitch. Those are they only two explanations for anything that doesn't work.
And people wonder why Bubba gets grumpy....


Will.

 

[labeledas]

Although I will say I have seen it on at least 2 occasions where the plc code never necessarly changed but a set of odd conditions and very poorly written programs cause a system that ran for years to suddenly started acting strangely.

So not so much the plc code changing but the plc was actually to blame

 

[padees]

I'll take a neutral stance on this issue because I'm in the middle between both sides of the story.

I have seen some horrific programming which needed to be fixed or blown away and start fresh, as well as pay me to drive to another state to adjust a proximity switch that their maintenance guy was afraid to mess with.

Most of my ventures are fixing the horrific programs tho, and there is a lot of bad stuff out there. There really is.

Like I say, I am neutral to this tho.

 

[Boorabee Parker]

Just yesterday (Saturday) had to replace a control module on a AB soft starter for a chipper. This was a break module, with a pump module being used to keep things going after the original failed. Swapped over modules, downloaded parameters using CCW, started and stopped drive all good. I only started the drive itself, not the whole waste system.

Just about home get a call the sawdust system would not start and it must be my fault. I did not work on this system, but did power down the controls for it. Ok, I go back and try to start the sawdust system from the HMI, no go. Looked over at the MCC and could see the safety circuit reset indicator was not on. Went over, pushed the reset, up came the safety circuit, then went to the HMI and started sawdust system. Did not see Bubba at all, luckily for him.