One hole straps, up or down?

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One hole straps, up or down?

  • Up (Mounting hole above conduit)

    Votes: 25 16.0%

  • Down (Mounting hole below conduit)

    Votes: 63 40.4%

  • Alternate them

    Votes: 15 9.6%

  • Whatever looks good at the time.

    Votes: 29 18.6%

  • Never worried about it and will not start now.

    Votes: 24 15.4%
  • Total voters
    156
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jumper

jumper

Senior Member
Location
3 Hr 2 Min from Winged Horses
nakulak said:
the notion that calculus would be required to calculate the simple mechanics or dynamics of this problem, whether including the deformable portion or not, is a little over the top imo. I am of the opinion that Karl is correct, but I also realize that the problem (in terms of its finite technical description) has yet to be adequately described. For example, consider the following widely varying parameters:
1) pipe size (I'm sure this conversation was mostly about 1/2 or 3/4 ?)
2) anchor type
3) screw type and size
4) washer used or not used (a critical issue for lower density substrates)
5) substrate (critically important, and probably overriding factor)
6) the strap itself (cheap metal strap or rigid strap - again a vital factor)
While the conversation has rambled through all these pages, everyone posting may have widely different trade practices as to what they had envisioned regarding the above, and because the physics of the problem was not precisely identified, the conversations may have been about completely different installations (with the relative strengths of the differing materials varying to such a wide degree).

- just my 2 cents
Click to expand...

I agree, calculus in this install probably has no bearing, as you state different variables come up with different answers. The physics were not defined and I agree with you.
 
D

Doug S.

Senior Member
Location
West Michigan
So I thought I'd help Iwire get his prediction... (See post #2) (346 to go...)

I voted to alternate. =)

I also think there is a time and place for either and most of the time it doesn't freak'n matter.

So since I refuse the read most of the last 15 pages, did some one bring up the white-book yet? Or specific listing info? :wink:

AND since I'm typing about straps I'd like to mentioned I HATE the flimsy straps that one can often find at the big-box stores. Give me my 1/8" thick OZG straps!!! Anchored correctly the should outlast the raceway!

My 2?
Doug S.
 
LarryFine

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
nysparky said:
if pipe strap is underneath the pipe and loosens up for some reason,the pipe won't fall. down.....
Click to expand...
I'll take not loosening over tolerating loosening any time. :cool:


If the strap is lying back, haven't we lost "secured" and only have "supported" now?
 
A

ashtrak

Senior Member
Location
Maryland
Up or Down

Up or Down

Like I was told when when I was a first year apprectice and asked the up or down question!

"Pipe can't fall up, stupid apprentice boy"
What a great mentor.What a great time in my life, ha,ha,....
 
O

ohm

Senior Member
Location
Birmingham, AL
Doug S. said:
So I thought I'd help Iwire get his prediction... (See post #2) (346 to go...)

I voted to alternate. =)

I also think there is a time and place for either and most of the time it doesn't freak'n matter.

So since I refuse the read most of the last 15 pages, did some one bring up the white-book yet? Or specific listing info? :wink:

AND since I'm typing about straps I'd like to mentioned I HATE the flimsy straps that one can often find at the big-box stores. Give me my 1/8" thick OZG straps!!! Anchored correctly the should outlast the raceway!

My 2?
Doug S.
Click to expand...

I thought the same thing Doug.

2007 White Book: DWMU The mounting orientation, if restricted, shall be marked on the carton or installation instructions.

I've poured over the various manufacturers and haven't found anything restrictive.

The American Electrician has nothing.

None of the textbooks I've used teaching at a community college have nothing on the subject.

Seems this thread has all the experts on the subject.
 
K8MHZ

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
I dug around a bit and found that in order to be UL listed for electrical conduit support any restriction on installation orientation must be printed on the package or in some form of nomenclature in the package.

I did find a restriction for using one hole straps on CPVC that specified that the tab be installed up on horizontal runs.

What I did not find was how they were tested. Details of UL listings seem to only be available on a pay as you download basis.
 
K

Karl H

Senior Member
Location
San Diego,CA
bradleyelectric said:
what if some kids come by and beat on the bottom of the pipe? Commons scense says it would bend the band up and since the band is ancored from the top and the screw isn't under the pipe to hold it up. It could very well fall on the kid behind the 1 that was beating on pipes head killing him or her. I just can't let that happen.
Click to expand...

If you are running "large" pipe, that contains heavy conductors
that, if it were to fall,it would break the couplings, sever the wires,
and potentially put someones life in jeopardy. Then, (1) you didn't
support your conduit per the NEC. (2) You probably shouldn't be using
one-hole straps as a means to support the conduit.

Granted, Im old and a little out of touch with the fads today.
I just don't think it's the new rage for children to run around pushing up on
conduit runs. Please, remember I'm old and probably very misinformed.:smile:
 
steelersman

steelersman

Senior Member
Location
Lake Ridge, VA
Karl H said:
If you are running "large" pipe, that contains heavy conductors
that, if it were to fall,it would break the couplings, sever the wires,
and potentially put someones life in jeopardy. Then, (1) you didn't
support your conduit per the NEC. (2) You probably shouldn't be using
one-hole straps as a means to support the conduit.

Granted, Im old and a little out of touch with the fads today.
I just don't think it's the new rage for children to run around pushing up on
conduit runs. Please, remember I'm old and probably very misinformed.:smile:
Click to expand...


Nope. Your not misinformed. You are thinking clearly and using common sense.
 
O

ohm

Senior Member
Location
Birmingham, AL
LarryFine said:
Isn't that why you're here? :wink:
Click to expand...

Actually Larry, I've probably run less "pipe" than anyone here. The only saddle I'm comfortable with is on a horse.

This thread may sound silly but can you imagine how useful it may become if an inspector told you that you had to re-orient a few thousand straps?

I can learn something from yesterdays comic strip!

K8MHZ's find on CPVC sounds interesting. Does tab up mean hole up? If it's part of a PVC UL listing the physics would would probably apply to all types of horizontal conduit. I may have to cast another ballot!
 
480sparky

480sparky

Senior Member
Location
Iowegia
ohm said:
..........This thread may sound silly but can you imagine how useful it may become if an inspector told you that you had to re-orient a few thousand straps?
Click to expand...

I'd ask the inspector for a Code reference.


ohm said:
..........K8MHZ's find on CPVC sounds interesting. Does tab up mean hole up? If it's part of a PVC UL listing the physics would would probably apply to all types of horizontal conduit. I may have to cast another ballot!
Click to expand...

I thought CPVC was for plumbers.
 
K8MHZ

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
ohm said:
Not the inspector I met in TN! They do their own thing, and get away with it!

I thought CPVC was plumber stuff too. But maybe they're onto something.
Click to expand...

What about garden hose? I know a tin knocker that made a 30 amp 240 volt extension cord out of some scrap THHN and a hose and is proud of it.

Gotta admit, it's lasted over 4 years in his shop now. I wonder how long a chinese made cord would have lasted, UL listed or not?
 
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