Disconnecting Means Location

jap

Senior Member
Qualified service people have some protocol for safety - lock off is simple -- IF you are not qualified then thinning out the heard is the next option available.
I agree.

A disconnect being within sight or even within 50' of what you're working on, to me, does nothing to promote safety.

It's not like you'll be able to keep your eye on the disconnect the whole time your working on a unit anyway.

JAP>
 

kwired

Electron manager
Location
NE Nebraska
I agree.

A disconnect being within sight or even within 50' of what you're working on, to me, does nothing to promote safety.

It's not like you'll be able to keep your eye on the disconnect the whole time your working on a unit anyway.

JAP>
10 feet away might be hard to keep an eye on in some instances, so what is your suggestion other than to use 70E and lock out even if you will have fairly continuous eye on your disconnect? IMO NEC is fine with it's rules relating to this topic and if you want to be stricter with a safety policy that is still an option.
 

jap

Senior Member
10 feet away might be hard to keep an eye on in some instances, so what is your suggestion other than to use 70E and lock out even if you will have fairly continuous eye on your disconnect? IMO NEC is fine with it's rules relating to this topic and if you want to be stricter with a safety policy that is still an option.
I said above the safest thing to do is to lock out since you can't keep a constant eye on the disconnect regardless of how far it is away from the unit.

Not sure what your meaning by "what would be my suggestion other than to use 70E and lockout even if you will have fairly continuous eyes on the disconnect ?" when using a lockout is what I just mentioned.

JAP>
 

kwired

Electron manager
Location
NE Nebraska
I said above the safest thing to do is to lock out since you can't keep a constant eye on the disconnect regardless of how far it is away from the unit.

Not sure what your meaning by "what would be my suggestion other than to use 70E and lockout even if you will have fairly continuous eyes on the disconnect ?" when using a lockout is what I just mentioned.

JAP>
Sorry, I was thinking you were suggesting NEC requirement of 50 feet and in sight of were not sufficient, my point was even closer than that might still have some danger and that it is ok to have practices that go beyond NEC requirements.
 

jap

Senior Member
Sorry, I was thinking you were suggesting NEC requirement of 50 feet and in sight of were not sufficient, my point was even closer than that might still have some danger and that it is ok to have practices that go beyond NEC requirements.
I feel the rule is good as far as being able to find the disconnect.

If the rule is followed, at least you know the disconnect for something should be within a certain area.

However, when it comes to the safety aspect of working on piece of equipment, the disconnects physical location has little to do with safety.

The extra step of common sense and LOTO come into play at that point.

JAP>
 

kwired

Electron manager
Location
NE Nebraska
I feel the rule is good as far as being able to find the disconnect.

If the rule is followed, at least you know the disconnect for something should be within a certain area.

However, when it comes to the safety aspect of working on piece of equipment, the disconnects physical location has little to do with safety.

The extra step of common sense and LOTO come into play at that point.

JAP>
And situation can be different in one place vs another. If I am in middle of a cornfield all by myself and throw the disconnect that is within 50 feet of me to work on the center pivot machine, the chance of someone turning it on are not that great, unless maybe a raccoon sneaks up and turns it on.

Being a 1 man show I am fine with that. If I had several employees, I may still want them to practice locking it off anyway.

I have also been situation on such application but needed to shut power off on disconnect at the road, which may be 1300 or even 2600 feet away. Might lock that one, might remove fuses from it so if it does get turned on still won't send voltage down to me, kind of depends on circumstances at the time.

Electrocutions I have heard about in above situations often was one worker at the road disconnect, one at the equipment and miscommunication on when to turn the switch on.
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
440.14 Location. Disconnecting means shall be located within
sight from, and readily accessible from the air-conditioning or
refrigerating equipment. The disconnecting means shall be
permitted to be installed on or within the air-conditioning or
refrigerating equipment.
Maybe you could put the disconnect switch inside the equipment.
 

jap

Senior Member
You could if you wanted to.

I'm sure some would argue about the "readily accessible" part.

Many job specs require disconnects provided with equipment and that's where most manufacturers put them.

JAP>
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
You could if you wanted to.

I'm sure some would argue about the "readily accessible" part.

Many job specs require disconnects provided with equipment and that's where most manufacturers put them.

JAP>
seems to me that specifically allowing the disconnect to be inside the equipment if you chose that option you are exempt from the readily accessible and within sight requirements.
 

jap

Senior Member
That would be my argument, although to me a disconnect located inside of a piece of equipment is somewhat defeating it's purpose.

JAP>
 

jap

Senior Member
My understanding is that the internal disconnect must be externally operable.
And doesnt that seem odd?

Why should an internal disconnect be required to be externally operable when it doesn't disconnect the power that's inside of the unit to begin with ?



Jap>
 

readydave8

re member
Location
Clarkesville, Georgia
Occupation
electrician
And doesnt that seem odd?

Why should an internal disconnect be required to be externally operable when it doesn't disconnect the power that's inside of the unit to begin with ?



Jap>
I always thought it's because the bigger danger is my hand getting hit by fan rather than danger of electrical shock
 

retirede

Senior Member
Location
Illinois
And doesnt that seem odd?

Why should an internal disconnect be required to be externally operable when it doesn't disconnect the power that's inside of the unit to begin with ?



Jap>
Very useful for the mechanic when working on said machine. He doesn’t have to call the plant electrician in order to power down the machine.
 

kwired

Electron manager
Location
NE Nebraska
I always thought it's because the bigger danger is my hand getting hit by fan rather than danger of electrical shock
Not always a fan in the equipment. Plus as mentioned maybe you are disconnecting a machine so that you isolate chances of the machine starting to do something besides work in the main electrical panel of the machine. Operator changing a cutting blade or grinder parts or maybe even simply cleaning the machine- only needs to be assured there is no mechanical energy potential for their task.

For the maintenance/electrician that is going to work in main panel, nothing wrong with building it so that main disconnect is housed in it's own protected compartment so there is no exposure to the line side components when the main panel cover is open. Still can design it so an external handle won't let you open the main cover until the disconnect is open as well.
 
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