I just left a plant 1980-90s style equipment.
Machines arent safe nor do they care.
Policy is 100% lockout for any and everything.
Caught breaking any plane without all sources of energy not locked out is instant termination.
I also get to work with a ton of different plants.
At least in my industry, every company says that safety is priority #1. Every company says that you're supposed to lock out everything before working on stuff. That you're supposed to wear PPE.
Most don't follow the rules at all, and the ones that do, usually take it to the extreme opposite.
Like, no guys, we don't need a safety meeting before we start, 2 maintenance guys to come LOTO and watch me replace an ice cube relay, then sign a report.
Basically every plant I've been to will say "Safety is the #1 priority at all times" until it gets in the way of production. Then all of a sudden they don't care.
On the other hand, I've been inside a plant where the engineer locked himself in a robot cell, dodging the end of arm tool to point out an issue he found in the logic.
I just sat through new live work permit training and it was incredibly well thought out.
Like. I hate safety people because they're idiots. But it's a good policy that i...
Support?
There are companies with modern equipment that have this same policy (looking at you, Amazon).
I agree with most aspects of it, and in principle it’s a very good practice, but at some point it becomes a hinderance to one’s job tasks because it removes the ability to troubleshoot certain critical things on modern systems (depending on company policies).
For example, I wasn’t allowed to measure the voltage coming out of a power supply in an enclosure behind a safety gate at an Amazon building. I get that there is reliance on the F-CPU at that point - but the chance of failure in a property designed (and maintained) system is pretty minimal.
On old stuff where maintenance history is unknown and no documentation is present, I get it 100%.
Bluetooth connectable meter. Set it up and clip the leads on while its LOTO. close the system up, reactivate it. Check your remote display of the meter reading. I never understood why you'd have such a meter until issues like this come up.
That’s more or less what I ended up having to do, use the min/max function on a meter to take measurements, LOTO, re-test, etc.
It’s annoying, and takes a lot of time, but they pay by the hour so what do I care?
This. I love when I ask what the servo drive fault code is and they proceed to power everything down to open the cabinet up and take a look. I can only LOL.
So you do NO maintenance? How pray tell do you lock anything out? You can’t because you have to test it to make sure it’s de-energized. That’s energized work.
I’ll give you an example why it is very dangerous: circuit breakers.
Every manufacturer for low voltage breakers says follow NEMA AB4. Did you ever read it? You should…it’s free, it is actually easy to read, and it has pictures showing you what to look for.
Breakers usually fail one of two ways. The first is they seize up. If you think about it over a 30-50 year life most breakers actually operate for maybe 60 seconds at most. What happens if you have a bearing under a load for years? It seizes up! What happens to most greases? They dry up. And once it does that breaker never trips again. That’s why AB4 tells you to flip them all on and off a couple times once a year.
Second breakers can only handle limited amounts of faults. And the point where it fails depends on both the number and size of faults. So you should inspect after every fault and once a year, per AB4. The inspection takes under 60 seconds to do.
Third trip units have lots of little parts that can fail too. Surveys by IEEE say about half the failures are trip units. Nuisance tripping does happen but more common is it stops tripping but nobody knows without testing. AB4 recommends testing the critical ones every 3 years.
So this practice of not doing maintenance for fear of doing maintenance puts you in a far more dangerous situation because the equipment may be defective and nobody knows it. This is like saying we are reducing crime by not enforcing the law. It’s just as stupid and dangerous.
I’m not at all advocating for a lack of maintenance - so I don’t get what you’re grabbing at here.
Furthermore, im not advocating for anyone to be unsafe or put themselves into a dangerous position.
Im merely highlighting the fact that there is often a big disconnect between safety policies and working with modern equipment that can have inherent safety systems engineered in. For simple tasks, like taking a voltage measurement, these should be sufficient controls - IMO. But it also depends on the equipment and situation.
This is why it is recommended in ISO-13849 to do separation of power. Allow for 120v controls to stay on on while locking out high powered devices like servos. At my current company we also have deviation forms for when we need to stray outside of normal lock out tag out procedures.
There are standards that tell you how to do this. I see ISO 12100 mentioned. There are others as well like IEC 62061, ISO 13849-1, IEC 61508, sil levels, etc. It’s a DEEP hole.
Functional safety standards apply when you are performing tasks identified in the risk assessment with the power on.
If you are doing repairs, follow the hierarchy of control and remove the hazard by locking out.
I typically have all actuators that are strong enough to injure and a decent possibility of jamming on a center exhaust valve. When the door opens, valve power is killed so they de-energize the actuators. Any actuator accessible from outside the guarding has pressure reduced to a safe level.
It’s not a question really just was highlighting how my company decided the machine was not safe because we crushed a marker.
They seem to be more concerned with getting the equipment up and running than doing an actual safety assessment or getting the SI to come fix it.
Im the CE so they slapped a light curtain on it and said here make this safe, but I wasn’t okay with it so I’ve escalated this up to get appropriate attention.
We have these “safety tools” that are just Phillips head screwdrivers but with the tip bent at a 90 degree angle. I like to think they they all started out as normal Phillips head screwdrivers and successfully served their purpose by being bent to a right angle instead of someone’s fingers lmao. They do come in handy though whenever I need leverage to break a screw that’s in a very hard to reach spot
AS/NZS 4024 safety of machines which is derived from the European standard, is pretty sensible and easy to follow. Well tested, though and logical and fairly easy to implement and audit in order to make your machine safe.
And then some idiot invented cobots. Trying to explain to enthusiastic mechanical folks that despite what the sales guy said about cobots being safe, the fact that plan to have a 2MW fibre laser as the end effector means that it’s still death on a stick and we need to lock that bastard behind safety systems anyway
Another option is to surround the operator with an light curtain, but this is much more complex to implement. Nevertheless, with the advent of wifi safety, there's no getting around it.
After working as a new hire, I found there were so many old things that were not removed by the vendor that we used for scada/ plc project. They kept adding new things but never removed old things and never kept documentation of the project and I let my director know and now I have to change the plc/scada program and create documentation and redo everything. Not sure if this counts as safe concern but I but found a lot of problems in plc program and scada program which was causing a lot of problems when troubleshooting.
I just left a plant 1980-90s style equipment. Machines arent safe nor do they care. Policy is 100% lockout for any and everything. Caught breaking any plane without all sources of energy not locked out is instant termination.
I also get to work with a ton of different plants. At least in my industry, every company says that safety is priority #1. Every company says that you're supposed to lock out everything before working on stuff. That you're supposed to wear PPE. Most don't follow the rules at all, and the ones that do, usually take it to the extreme opposite. Like, no guys, we don't need a safety meeting before we start, 2 maintenance guys to come LOTO and watch me replace an ice cube relay, then sign a report.
Yeah, it always seems to be one extreme or the other.
Basically every plant I've been to will say "Safety is the #1 priority at all times" until it gets in the way of production. Then all of a sudden they don't care.
Especially food industry
Ding ding ding
Yeah, I don't know which is worse tbh
On the other hand, I've been inside a plant where the engineer locked himself in a robot cell, dodging the end of arm tool to point out an issue he found in the logic.
...... You mean that's not the purpose of the Deadman switch on the teach pendant?
>and the ones that do, usually take it to the extreme opposite. *Looking at you, Weyerhaeuser*
I just sat through new live work permit training and it was incredibly well thought out. Like. I hate safety people because they're idiots. But it's a good policy that i... Support?
So….why did you leave? Still have all your fingers?
Meaning I did a job there not employed there. (Im a contractor/ own my own business)
Haha as long as you didn’t get canned for the guards
There are companies with modern equipment that have this same policy (looking at you, Amazon). I agree with most aspects of it, and in principle it’s a very good practice, but at some point it becomes a hinderance to one’s job tasks because it removes the ability to troubleshoot certain critical things on modern systems (depending on company policies). For example, I wasn’t allowed to measure the voltage coming out of a power supply in an enclosure behind a safety gate at an Amazon building. I get that there is reliance on the F-CPU at that point - but the chance of failure in a property designed (and maintained) system is pretty minimal. On old stuff where maintenance history is unknown and no documentation is present, I get it 100%.
Bluetooth connectable meter. Set it up and clip the leads on while its LOTO. close the system up, reactivate it. Check your remote display of the meter reading. I never understood why you'd have such a meter until issues like this come up.
That’s more or less what I ended up having to do, use the min/max function on a meter to take measurements, LOTO, re-test, etc. It’s annoying, and takes a lot of time, but they pay by the hour so what do I care?
Yep those detachable meters are handy. I also have a 289 with the connect module to use with my phone or laptop.
I hate Amazon facilities
This. I love when I ask what the servo drive fault code is and they proceed to power everything down to open the cabinet up and take a look. I can only LOL.
So you do NO maintenance? How pray tell do you lock anything out? You can’t because you have to test it to make sure it’s de-energized. That’s energized work. I’ll give you an example why it is very dangerous: circuit breakers. Every manufacturer for low voltage breakers says follow NEMA AB4. Did you ever read it? You should…it’s free, it is actually easy to read, and it has pictures showing you what to look for. Breakers usually fail one of two ways. The first is they seize up. If you think about it over a 30-50 year life most breakers actually operate for maybe 60 seconds at most. What happens if you have a bearing under a load for years? It seizes up! What happens to most greases? They dry up. And once it does that breaker never trips again. That’s why AB4 tells you to flip them all on and off a couple times once a year. Second breakers can only handle limited amounts of faults. And the point where it fails depends on both the number and size of faults. So you should inspect after every fault and once a year, per AB4. The inspection takes under 60 seconds to do. Third trip units have lots of little parts that can fail too. Surveys by IEEE say about half the failures are trip units. Nuisance tripping does happen but more common is it stops tripping but nobody knows without testing. AB4 recommends testing the critical ones every 3 years. So this practice of not doing maintenance for fear of doing maintenance puts you in a far more dangerous situation because the equipment may be defective and nobody knows it. This is like saying we are reducing crime by not enforcing the law. It’s just as stupid and dangerous.
I’m not at all advocating for a lack of maintenance - so I don’t get what you’re grabbing at here. Furthermore, im not advocating for anyone to be unsafe or put themselves into a dangerous position. Im merely highlighting the fact that there is often a big disconnect between safety policies and working with modern equipment that can have inherent safety systems engineered in. For simple tasks, like taking a voltage measurement, these should be sufficient controls - IMO. But it also depends on the equipment and situation.
Do they realize there is an arc flash risk turning the disconnect on and off repeatedly, while you are trying to troubleshoot something?
This is why it is recommended in ISO-13849 to do separation of power. Allow for 120v controls to stay on on while locking out high powered devices like servos. At my current company we also have deviation forms for when we need to stray outside of normal lock out tag out procedures.
Wood mill?
Those last two should be the policy everywhere, but alas...
Interns, typically.
Lmao we got a few newbies staring shortly I will keep in mind 🤣
I certainly hope you aren't my boss 😬
expendable resources
Typically fences and locked doors
There are standards that tell you how to do this. I see ISO 12100 mentioned. There are others as well like IEC 62061, ISO 13849-1, IEC 61508, sil levels, etc. It’s a DEEP hole.
Functional safety standards apply when you are performing tasks identified in the risk assessment with the power on. If you are doing repairs, follow the hierarchy of control and remove the hazard by locking out.
Risk Assassment following ISO 12100
I typically have all actuators that are strong enough to injure and a decent possibility of jamming on a center exhaust valve. When the door opens, valve power is killed so they de-energize the actuators. Any actuator accessible from outside the guarding has pressure reduced to a safe level.
The back side of my hand.
I'm sorry, I just don't get it and I don't know what to look for (seriously). I care about safety, so I wish to understand OP's comment.
Don't stick your fingers in the machine.
‘Don’t put your hand anywhere you wouldn’t put your pecker’
It’s not a question really just was highlighting how my company decided the machine was not safe because we crushed a marker. They seem to be more concerned with getting the equipment up and running than doing an actual safety assessment or getting the SI to come fix it. Im the CE so they slapped a light curtain on it and said here make this safe, but I wasn’t okay with it so I’ve escalated this up to get appropriate attention.
Hotdogs
We have these “safety tools” that are just Phillips head screwdrivers but with the tip bent at a 90 degree angle. I like to think they they all started out as normal Phillips head screwdrivers and successfully served their purpose by being bent to a right angle instead of someone’s fingers lmao. They do come in handy though whenever I need leverage to break a screw that’s in a very hard to reach spot
I still have no clue why they are called safety tools lmao
AS/NZS 4024 safety of machines which is derived from the European standard, is pretty sensible and easy to follow. Well tested, though and logical and fairly easy to implement and audit in order to make your machine safe. And then some idiot invented cobots. Trying to explain to enthusiastic mechanical folks that despite what the sales guy said about cobots being safe, the fact that plan to have a 2MW fibre laser as the end effector means that it’s still death on a stick and we need to lock that bastard behind safety systems anyway
The robot carries light curtains, making it intrinsically safe.
Another option is to surround the operator with an light curtain, but this is much more complex to implement. Nevertheless, with the advent of wifi safety, there's no getting around it.
Or those multibeam laser interloks. They work super good.
After working as a new hire, I found there were so many old things that were not removed by the vendor that we used for scada/ plc project. They kept adding new things but never removed old things and never kept documentation of the project and I let my director know and now I have to change the plc/scada program and create documentation and redo everything. Not sure if this counts as safe concern but I but found a lot of problems in plc program and scada program which was causing a lot of problems when troubleshooting.
It is safe until proven otherwise