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Cord Drops #99898
09/25/06 07:32 PM
09/25/06 07:32 PM
electure  Offline
OP
Member
Joined: Dec 2000
Posts: 4,274
Fullerton, CA USA
The subject of cords came up in another thread, so as long as cords are a topic as of late..........

How do you guys feel about the practice of hooking up machinery in industrial settings with cords drop from the overhead? For a hypothetical instance a machine bolted to the floor, say 10 feet long, leveled to within thousandths of an inch, maybe 5 or 10 horsepower. It's never intended to be moved.
A connector body on the end of a cord that drops from a box above, and a cord and plug are field connected on the machine.

What are your thoughts?



[This message has been edited by electure (edited 09-25-2006).]

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Re: Cord Drops #99899
09/25/06 08:13 PM
09/25/06 08:13 PM
I
iwire  Offline
Moderator
Joined: Jan 2003
Posts: 4,391
North Attleboro, MA USA
I hate cord drops.

In some industrial locations I think they have a place as many times the equipment is only in place for a relatively short time.

However I do see them used in many locations just because it's easier with the excuse given 'vibration'


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Re: Cord Drops #99900
09/25/06 08:14 PM
09/25/06 08:14 PM
HotLine1  Offline

Member
Joined: Apr 2002
Posts: 7,036
Brick, NJ USA
'Cord' drops, as you described are NG.
400.7 Allowed uses does not fit your description.

That said, IF the unit has a cord and male cap, and said cord reaches the twistlock receptacle mounted on the ceiling, that's another story.

As you stated, this is a much debated subject.

John


John
Re: Cord Drops #99901
09/25/06 08:17 PM
09/25/06 08:17 PM
HotLine1  Offline

Member
Joined: Apr 2002
Posts: 7,036
Brick, NJ USA
Bob:
The vibration 'lemme get away with it this time' excuse does not fly here.

As you said, under the right circumstances; equipment that has to be 'moved' for cleaning (FDA & Health Dept), truly "portable" equipment, etc.

John


John
Re: Cord Drops #99902
09/25/06 08:28 PM
09/25/06 08:28 PM
D
Dnkldorf  Offline
Member
Joined: Dec 2004
Posts: 1,064
nowhere usa
John, just for the point of discussion, what is the difference between a receptactle in a box, and a female plug on a cord?

Where is there a hazzard, and what if the cord drop was intended to be shared between 2 different pieces of equipment?

Re: Cord Drops #99903
09/25/06 08:42 PM
09/25/06 08:42 PM
electure  Offline
OP
Member
Joined: Dec 2000
Posts: 4,274
Fullerton, CA USA
Dnk, one would be that when the machine is removed, there isn't 20' or so of cord left attached to the building, which will usually be coiled up and left hanging from the overhead to rot for eternity.

Re: Cord Drops #99904
09/25/06 08:58 PM
09/25/06 08:58 PM
renosteinke  Offline
Cat Servant
Member
Joined: Jan 2005
Posts: 5,316
Blue Collar Country
I like cord drops. That's all there is to it.

First of all, anything that gets the wiring out of the way gets my vote. I've seen way too much damage from trips, getting bumped into, etc.

Even when the machine is never going to be moved, is absolutely without vibration, etc... quite often covers are removed, raw material is transported, etc. A cord has some "give," and a plug will come out before damage occurs (usually). Much preferablt to having a poor forklift maneuver result in sparking, non-continuous pipe.

There is also the issue that pipe that drops down from a 20 ft ceiling is in no way properly supported- not in my book. And my supplier is fresh out of skyhooks. I'd rather see a properly strain-relieved length of S drop directly to the machine.

Re: Cord Drops #99905
09/25/06 09:38 PM
09/25/06 09:38 PM
L
LoneGunman  Offline
Member
Joined: Oct 2005
Posts: 141
Florida
Agree with John 100%. Spent a lot of time when I first got into the trade in a very large machine shop. We used mostly SJ drops due to machines getting moved even when they were supposed to be permament and saw a lot of conduit damage from fork lifts ETC. The SJ being flexable held up better. We'd pipe to directly over the machine, add a box and then make an SJ drop.

What bothers me was seeing SJ tie wrapped to trusses and in places down low subject to physical damage.

Re: Cord Drops #99906
09/25/06 09:46 PM
09/25/06 09:46 PM
I
iwire  Offline
Moderator
Joined: Jan 2003
Posts: 4,391
North Attleboro, MA USA
Quote
There is also the issue that pipe that drops down from a 20 ft ceiling is in no way properly supported- not in my book


So get off your rear and properly support it. [Linked Image] [Linked Image]

Double strut, steel tubing etc.


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Re: Cord Drops #99907
09/25/06 09:59 PM
09/25/06 09:59 PM
electure  Offline
OP
Member
Joined: Dec 2000
Posts: 4,274
Fullerton, CA USA
Would the same "flexibility theory" apply to all surface wiring within reach of a forklift? There is often conduit run all over machinery, and I've seen plenty of fork holes through walls.

Do you disagree that a drop to a permanent installation does not meet Code?

[This message has been edited by electure (edited 09-25-2006).]

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