Hot swapping of electrical parts

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leeradney

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Dublin, GA USA
We are currently doing some Economic Development training for a local industry. They have adamantly stated that they will need to be able to hot swap electrical parts while power is applied.

We have provided them with OSHA'S stance on the matter (essentially the employee would have to be at greater risk with the power off, than with power applied).

That said, are any of you familiar with any industry that would have a case for hot swapping of parts (we are not) and if so, do you know who conducts this type of training for their employees?

Thank you for your time. And for the record, we proudly teach lockout tagout. So please, don't shoot the messenger.

Sent from my Commodore 64
 
leeradney said:
That said, are any of you familiar with any industry that would have a case for hot swapping of parts (we are not) and if so, do you know who conducts this type of training for their employees?

Sent from my Commodore 64
Click to expand...

yes. you can hot swap the flux capacitor on your delorean,
but only when you are back in the past, about the time that
your Commodore 64 was the flower of technology.

if you are in the present time, you have to LOTO the delorean
before you touch that flux capacitor. you can't even open the
disconnect without an arc flash rating, and proper PPE.

in the present time, the only hot swapping training that is available
is from an attorney, representing you after something goes very
wrong with this plan, who will hot swap money from your pocket to his pocket.
 
retirede said:
:) :)

Seriously, can they give you an example of the type of equipment and associated processes where this would be deemed necessary?
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They manufacture glass fiber. I was told that even 1 second of the furnace being off is detrimental to their product. Apparently "Bob" the electrician is not quite as important. :D
 
Fulthrotl said:
yes. you can hot swap the flux capacitor on your delorean,
but only when you are back in the past, about the time that
your Commodore 64 was the flower of technology.

if you are in the present time, you have to LOTO the delorean
before you touch that flux capacitor. you can't even open the
disconnect without an arc flash rating, and proper PPE.

in the present time, the only hot swapping training that is available
is from an attorney, representing you after something goes very
wrong with this plan, who will hot swap money from your pocket to his pocket.
Click to expand...

WOW:D
 
It sounds like the company needs to invest in some redundancy. Something similar to a ring bus in transmission substations for isolating breakers for maintenance while still keeping the machines running.
 
there are some processes where even a short interruption will cause unimaginable damage to the plant. They are quite rare and I seem to recall there is some kind of dispensation OSHA allows for this. I suspect your hazard analysis is going to have to be real solid to support any claims you make about such a situation.

however, the OP has not stated just what it is he wants to "hot swap". It seems to me if he is swapping it out it is already dead so there might be some way to isolate it already so it can be worked on while it is dead.

There are also some things that can be hot swapped like certain PLC I/O cards. Suppose you could arrange it so the employee is only exposed to 24VDC. That is not considered hazardous by NFPA70E so one could work while that kind of system is energized.

You are probably going to have to look at your equipment and rebuild some of it so it is possible to isolate things properly that need to be replaced if you want to avoid unplanned downtime.
 
petersonra said:
there are some processes where even a short interruption will cause unimaginable damage to the plant. They are quite rare and I seem to recall there is some kind of dispensation OSHA allows for this. I suspect your hazard analysis is going to have to be real solid to support any claims you make about such a situation.

however, the OP has not stated just what it is he wants to "hot swap". It seems to me if he is swapping it out it is already dead so there might be some way to isolate it already so it can be worked on while it is dead.

There are also some things that can be hot swapped like certain PLC I/O cards. Suppose you could arrange it so the employee is only exposed to 24VDC. That is not considered hazardous by NFPA70E so one could work while that kind of system is energized.

You are probably going to have to look at your equipment and rebuild some of it so it is possible to isolate things properly that need to be replaced if you want to avoid unplanned downtime.
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The OP is not hot swapping anything. He is doing training as a third party.
 
The other consideration when working it hot is if you are wearing proper PPE, things are more difficult to handle with that PPE on, it may be easier to short something out and ultimately shut the process down anyway.

One needs to design things so they are easier to swap while hot, or easier to isolate non critical items without shutting down the entire process. You would also likely need some redundancy in critical items, and maybe ways to isolate those redundant items to work on them.
 
Yeah, sounds like the manufacturer needs to do some redundancy work on their end. I've worker in the data center side for years. They don't like to lose power on their servers because that's money lost. Most have been set up with UPS systems, ATS's and multiple POCO feeds. This way I could isolate power on PDU's and do any work necessary without taking down their customers. Point being, if the site was properly engineered, there should be a way to isolate equipment for maintenance without affecting the rest of the facility. If they're not set up that way then the answer would be, "sorry, power will be off while swapping equipment"

Jason
 
It's a glass fiber manufacturer. So the area I am speaking of would be the controls side, some of which is three phase. They state that even a few seconds of furnace downtime is detrimental to product quality. It seems that this hot swapping is fairly frequent in their Eastern European factory. :eek::eek:
 
drcampbell said:
And how frequent are electrocutions? How frequent would you like them to be?
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This is why, for the trainees we have, we reiterate the code to them. However, the company seems adamant. This is why I wanted to see if anyone knew of legal exceptions and proper training. We are certainly not advocating this process.
 
leeradney said:
This is why, for the trainees we have, we reiterate the code to them. However, the company seems adamant. This is why I wanted to see if anyone knew of legal exceptions and proper training. We are certainly not advocating this process.
Click to expand...

Again, lacking specifics. Specific tasks, if justified to create a larger hazard to de-energize that work hot can be done with specific task based training and an EEWP which is issued each time the task needs to be performed. Custom classroom and hands on training for the workers is required (All the details of the trailing are in the 70E)and employees must have documentation of the training for each specific task they are "qualified" to do, then an EEWP is issued and the task is performed wearing the correct shock and arc flash protection PPE as determined by an engineering analysis.

I developed this type of training for major auto and steel manufactures for many years, there is a lot that goes into it, not something that can be easily answered here.
 
lots of plastic & rubber. being bonded is "safe" ;)

3XRG3_AS04


NEW-1-Pair-Insulating-font-b-Gloves-b-font-Rubber-Safety-Electrical-Protective-Security-Safely-font.jpg
 
zog said:
Again, lacking specifics. Specific tasks, if justified to create a larger hazard to de-energize that work hot can be done with specific task based training and an EEWP which is issued each time the task needs to be performed. Custom classroom and hands on training for the workers is required (All the details of the trailing are in the 70E)and employees must have documentation of the training for each specific task they are "qualified" to do, then an EEWP is issued and the task is performed wearing the correct shock and arc flash protection PPE as determined by an engineering analysis.

I developed this type of training for major auto and steel manufactures for many years, there is a lot that goes into it, not something that can be easily answered here.
Click to expand...

The only apparent "hazard" is to product quality, and hence, company profits. I'm going to go out on a limb here and suggest that this reason is unlikely to pass muster with OSHA. :roll:
 
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