Question concerning Light Curtains!

[russrmartin]

I'm with Bruce

First of all, I thought this was a forum to share ideas, not to bash others. Second, the relying on others that you are talking about are OSHA inspectors, and yes, this forum is always a good place to ask others about ideas, after all, what do you use it for?, or are you so smart you never have to ask? May be possible, but I doubt.
Third, if you dont know to do this, you should not be messing with this ---- Well, if you consult with OSHA then you find out exactly what needs to be done, unless you just happen to be one of those that knows everything, like maybe yourself.
Also, as far as you being liable for killing or hurting someone - Well that is why OSHA was consulted, as well as our corporate lawyers to ensure that everything was as safe as possible.
And yes, myself and I am sure others use this forum to possibly get advice and maybe even to help someone, but never to bash.
I found out a long time ago that there is always someone out there who knows a better way, and I also found out that it is very easy to bash someone when you do not have to worry about meeting them face to face, after all, there are some folks on this earth that you will run into that it is best not to mess with, but if you never have to run into them, then i guess its okay to talk.

After all, this forum, but the best i have been able to tell is a great place to share info and idea's, seems to me if you not willing to do that, then maybe you should take up golfing or something else.

Hounddog,

I read your post, then reread Bruce's, and I'm with him. He was not bashing anyone, it appears to me that he was just cautioning the original poster of the magnitude of the subject. Getting ideas is great, but getting ideas regarding safety issues and implementing them without the correct expertise and knowledge in place is just a bad situation for anyone. Not only is it poor for the future operators, but could also be bad for the original poster as well.

To reword what Bruce is saying, there is what is called a risk analysis which should be performed by a team which includes the original poster, the project requester/engineer, a safety representative, as well as anyone else who may have valuable input. From this risk analysis will come the requirements of the project to satisfy OSHA standards.

In my mind, all of this should be completed prior to the post. For the record, we have not nor will we ever have an OSHA inspector inspect anything, unless of course there is an incident. The methodology Bruce is referring to is a proven method to correctly identify and eliminate the hazards of the operation according to OSHA guidelines. Usually here that means that a SIL rating is defined in the Risk Assessment and must be followed. If this is done, the original poster then can ask for ideas on how to accomplish this.

In closing, it appears to me that Bruce Chase's post was merely a warning of caution not to just seek out opinions online and then follow through with the most popular idea.

Best of luck in the installation.

Russ

 

[hounddog]

you have a good day

 

[hounddog]

Hounddog,

I read your post, then reread Bruce's, and I'm with him. He was not bashing anyone, it appears to me that he was just cautioning the original poster of the magnitude of the subject. Getting ideas is great, but getting ideas regarding safety issues and implementing them without the correct expertise and knowledge in place is just a bad situation for anyone. Not only is it poor for the future operators, but could also be bad for the original poster as well.

To reword what Bruce is saying, there is what is called a risk analysis which should be performed by a team which includes the original poster, the project requester/engineer, a safety representative, as well as anyone else who may have valuable input. From this risk analysis will come the requirements of the project to satisfy OSHA standards.

In my mind, all of this should be completed prior to the post. For the record, we have not nor will we ever have an OSHA inspector inspect anything, unless of course there is an incident. The methodology Bruce is referring to is a proven method to correctly identify and eliminate the hazards of the operation according to OSHA guidelines. Usually here that means that a SIL rating is defined in the Risk Assessment and must be followed. If this is done, the original poster then can ask for ideas on how to accomplish this.

In closing, it appears to me that Bruce Chase's post was merely a warning of caution not to just seek out opinions online and then follow through with the most popular idea.

Best of luck in the installation.

Russ

Thanks for info panic mode, your post are always helpful.
there was a risk analysis done before I did any work on the machine. there was a operator who got a finger cut off, so OSHA came in and that was when I was asked to get involved.
At that time had no idea how use light curtains for point of entry etc., thats when I went on this site and searched for info pretaining to which regulations etc. pretain to press type operations etc., as well as another forum site, then i was able to download those regulations and study them.
When I went out to the OSHA webpage there was so much info, had no idea where to start, and our corporate safety manager was not much help.
Then when it was completed our corporate safety person as well as a representive from OSHA reviewed the operations of the machine to determine if it was safe to operate. Had to make sure that no matter what nothing could enter the area of operation after it was loadeded and could not be loaded until all operations where finished and everything at home postion.
Did what I could without being a expert on safety regulations, but info from this site from folks as your self and others helped determine which direction to go and research.
Now back to posting and asking questions, that was how I found out which regulations etc. to download and study. That was how this site as well as others was very valuable.
I was giving a regulations guide by our corporate saftey manager that was from OSHA, but after reading it was still confused, since OSHA saftey etc, was not my area, and some post on this site as well as some others where very helpful.
Sorry for the uproar, but took it personal, and should not have.

 

[OkiePC]

Nice dwg, hounddog...

[font=Courier New, monospace]Hounddog, glad your skin in thickening.[/font]

[font=Courier New, monospace]As a semi-experienced observer with a very limited perspective of your design, but a very similar perspective as far as finding information, I think your design is "pretty safe", but what is that worth?[/font]

[font=Courier New, monospace]Having been involved in fixing at least a dozen dangerous control systems, I share Bruce's passion about safety, but his comments were to serve as a striking warning to the OP, more than you.[/font]

[font=Courier New, monospace]I once watched a machinist snap off his pinky on a lathe spinning at 3000rpm because he was wearing a glove. I was standing behind him watching him polish a shaft with emery cloth, thinking to myself "he should not be wearing gloves..." It jerked the lathe to a stop and literally snapped off his pinky as the lathe jerked to a near stop, pulling the tendon out all the way up to his elbow.[/font]

[font=Courier New, monospace]I once had to crawl under the legs of a screaming co-worker and manually operate the opposite side of a two position double solenoid valve that had his right phalanges (all of them) clamped in a serrated pneumatic steel belt splicer, because the designer didn't think of using a single solenoid with spring return to release the air in the spring supported machine when the safety circuit dropped out power to the Mac-stack...[/font]

[font=Courier New, monospace]Luckily, after a year or two, Chuck can use his fingers at about 80% and didn't lose any of them.[/font]

[font=Courier New, monospace]That design had a four foot square safety mat under it but operators will be operators. It is just a matter of time until they evolve their methods to minimize button presses.[/font]

[font=Courier New, monospace]Chuck had unconsciously learned to step to the side of the mat to reach into the splicer when required, since then he could go right back to auto and move on to other tasks when he was done.[/font]

[font=Courier New, monospace]That awful day, he missed the stop button as he marched up to the machine, and reached in right as the splicer came down. Naturally he screamed like a little girl and stomped on the mat taking power away from the valves effectively locking it in place.[/font]

[font=Courier New, monospace]I was at the windups 50feet away and the area manager was standing right by him, trying to lift him off the mat and reset the safety at the same time (which would have released him). It took a good fifteen seconds to get him out and I will never forget it.[/font]

[font=Courier New, monospace]The designer of a control system can be sued personally, but that is not the reason to be extra careful and passionate about safety.[/font]

[font=Courier New, monospace]The designer of the splicer controls was an articulate, thorough, degreed electrical engineer with over 15 years of experience in industrial controls. A real super smart guy who seemed to think of everything.[/font]

[font=Courier New, monospace]Missing fingers, broken arms, and ruined lives are the reasons to keep your ego in check, and exercise prudence.[/font]

[font=Courier New, monospace][/Soapbox][/font]

[font=Courier New, monospace]Lost in all this was something touched on by Ndzied1. Now that you are still dusting off your britches, you should be open to a suggestion:[/font]

[font=Courier New, monospace]Tomorrow, or as soon as you get back to work, wire the NC contact of S4 to a monitored input which should be available as a muting input, probably located in the LCR (light curtain receiver).[/font]
[font=Courier New, monospace][/font]
[font=Courier New, monospace]If there is not a mute input that will work with that switch, then hook it up to a lamp that will go out when the plunger on hte switch moves and teach the operators to look at it to change states when they break the beam. [/font][font=Courier New, monospace]Then go to your PC or purchasing agent and order one of these:[/font]

[font=Courier New, monospace]As soon at it's received, wire a monitored inputs to SR1, and QUIT BYPASSING K1 and K2 with it. I was gonna read the manual for LCR, SR1 and make further suggestions, but if it has a muting input, USE IT, and add monitored contacts from K1 and K2 as inputs to the safety circuit so that any failure of the final electrical control elements can be detected by a safety rated controller that meets your assessed requirements.[/font]

[font=Courier New, monospace]Also, don't be offended, we all need to get knocked off our horse now and again.[/font]

[font=Courier New, monospace]Safety is urgent, serious, and never good enough. Waste no time in constantly improving it.[/font]

[font=Courier New, monospace]Paul[/font]

 

[grege101]

Just for everyones information:

I had no intentions of following through on any of the opinions or ideas posted here. Just thought I would ask a question and see what other people have done in past projects. As I posted earlier. An Engineer will be signing off on this. I have also been in contact with our pshr guy. He has given me some very good advice. I had no idea this was going to turn into a giant battle!! I also don't want to spend the rest of my days in jail beacause of some advice someone on the internet gave me. So, don't worry...I'm not that stupid! Thanks for looking out for my well being and the people that may have been seriously injured but this is far from what I expected.

Come on guys....Lets try and get along!

 

[OkiePC]

Just for everyones information:

I had no intentions of following through on any of the opinions or ideas posted here. Just thought I would ask a question and see what other people have done in past projects. As I posted earlier. An Engineer will be signing off on this. I have also been in contact with our pshr guy. He has given me some very good advice. I had no idea this was going to turn into a giant battle!! I also don't want to spend the rest of my days in jail beacause of some advice someone on the internet gave me. So, don't worry...I'm not that stupid! Thanks for looking out for my well being and the people that may have been seriously injured but this is far from what I expected.

Come on guys....Lets try and get along!

Part of getting along includes rigorous debate, and it is good to know you are making wise choices. Many visitors here, clearly, may not see everything the same way, and we are frequented by novices.

The 390 some odd viewers of this thread will benefit, even from the sometiomes emotional reactions. JMHOO

 

[brucechase]

There are good debates, there are emotional reactions, and then there's going too far. If you can't have a debate without getting into personal attacks, then that's a sad state of affairs.

There is one thing that most novices need to learn if they want to succeed in the business world and that is not to make it personal. Oh and by the way, you never know who you might be working for in the future.

I had no intentions of following through on any of the opinions or ideas posted here. Just thought I would ask a question and see what other people have done in past projects.
...
So, don't worry...I'm not that stupid! Thanks for looking out for my well being and the people that may have been seriously injured but this is far from what I expected.

It's good to get input from others. But even though you said an engineer will sign off on this, it sounds to me like the engineer should be designing this. As for not be that stupid, you might be surprised how many people will read something in a forum like this and take that as the absolute truth (especially inexperience engineers and techs). Like Paul (OkiePC), I've seen firsthand what an inadequate design will do to someone (losing a foot is not pretty). I've also seen firsthand someone defeat multiple interlocks and almost die (a 4160 VAC arc blast to the face). These things stay with you forever.

 

[hounddog]

Just for everyones information:

I had no intentions of following through on any of the opinions or ideas posted here. Just thought I would ask a question and see what other people have done in past projects. As I posted earlier. An Engineer will be signing off on this. I have also been in contact with our pshr guy. He has given me some very good advice. I had no idea this was going to turn into a giant battle!! I also don't want to spend the rest of my days in jail beacause of some advice someone on the internet gave me. So, don't worry...I'm not that stupid! Thanks for looking out for my well being and the people that may have been seriously injured but this is far from what I expected.

Come on guys....Lets try and get along!

here is a site that I think is great.
have learned a lot from it
think you will like it
http://forums.mrplc.com/index.php?showtopic=11577&hl=