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PeeWee
Premium
join:2001-10-21
Madera, CA
reply to 54067323

Re: How to calculate the amperage of paralleled conductors???

If you are doing this at a place of work you are nullifying any insurance coverage and assuming 100% liability if anything happens. How deep are your pockets? If you are doing this in your own home you are unnecessarily endangering your family, and the same thing with insurance.
--
Iphone. Helping computer illiteracy become popular since 2007


Bob4
Account deleted

join:2012-07-22
New Jersey
Reviews:
·Optimum Online

1 recommendation

reply to alkizmo

said by alkizmo:

Considering he needs around 50A, I'm guessing a heat pump or range.

Maybe a grow house?


pende_tim
Premium
join:2004-01-04
Andover, NJ
kudos:1
Reviews:
·Comcast
reply to 54067323

30 Amps max, if copper. depending on the insulation type and wire count in the conduit it may have to be derated.
--
The difference between genius and stupidity is that genius has its limits.


itguy05

join:2005-06-17
Carlisle, PA

1 recommendation

reply to PeeWee

said by PeeWee:

If you are doing this at a place of work you are nullifying any insurance coverage and assuming 100% liability if anything happens. How deep are your pockets? If you are doing this in your own home you are unnecessarily endangering your family, and the same thing with insurance.

Insurance covers stupidity. Just like "not using UL will void your homeowners" is not true. They may very well pay out one time and one time only but insurance will cover being stupid.

That being said it's unsafe and should not be done.


PSWired

join:2006-03-26
Annapolis, MD

2 recommendations

It's like someone's planning a nuclear apocalypse here every time a minor code violation is suggested. Good grief.

In the future we should be better at mentioning *why* the code prohibits things like this. People are much more likely to find a way to get their problem solved in a compliant manner if they understand the risks, rather than being told that the world will end for some unspecified reason if they don't do as they're told.



SparkChaser
Premium
join:2000-06-06
Downingtown, PA
kudos:3
Reviews:
·Verizon FiOS

PSWired See Profile], I understand what you are saying but 'it comes down to can you do that YES, should you NO.'

The problem with forums like this is (when it comes to electricity or gas or other dangerous "home" projects) , if you have to ask the question, you probably shouldn't be doing it.

No one want to be responsible for someone doing something stupid.
.
--
--
--
"Facts do not cease to exist because they are ignored." - Aldous Huxley



mattmag
Premium,ExMod 2000-03
join:2000-04-09
NW Illinois
kudos:3

said by SparkChaser:

The problem with forums like this is (when it comes to electricity or gas or other dangerous "home" projects) , if you have to ask the question, you probably shouldn't be doing it.

I most always respect your contributions, but that is just so not true. How else should a person teach? Is there not always a risk involved with *any* educational effort within a technological field?

I spent many years teaching EMT's to become a Paramedic. If they screw up, people can die. Should we not allow them to learn by doing? Of course not. One can't effectively learn how to start an IV simply by being told. We guide, we teach, we answer questions, and it all ends up furthering the education and skills of the student. There is always the risk, but the proper education is worth the chance.

I will always remember my dear mother telling me the story of how one night I stood in the kitchen as a wee young lad, and kept asking if the stove was hot. She kept telling me "Yes, it is hot". I kept asking. Finally, I touched the stove, and of course immediately jerked my finger back in pain. Sometimes learning by doing is the best teacher of all.

Bob4
Account deleted

join:2012-07-22
New Jersey

If someone comes on here asking if they can use a lighted match to search for a gas leak, you'd let them "learn by doing"?



guhuna
5149.5
Premium
join:2001-03-31
Clayton, CA
Reviews:
·PHONE POWER
reply to Bob4

said by Bob4:

said by alkizmo:

Considering he needs around 50A, I'm guessing a heat pump or range.

Maybe a grow house?

50amps for a grow op? Damn son that's small......

scooper

join:2000-07-11
Youngsville, NC
kudos:2
reply to 54067323

You know - I asked this same question six or more months ago (maybe more like 18), with basically the same answers. Maybe a good reason to have people read old posts before posting questions ?....



mattmag
Premium,ExMod 2000-03
join:2000-04-09
NW Illinois
kudos:3

1 recommendation

reply to Bob4

said by Bob4:

If someone comes on here asking if they can use a lighted match to search for a gas leak, you'd let them "learn by doing"?

I expected some sort of kindergarten reply such as this. I applaud you for your creativity and contribution to the thread.

Not.


Cho Baka
Premium,MVM
join:2000-11-23
there
kudos:2

1 recommendation

reply to Bob4

Some gasfitters do this.


TheMG
Premium
join:2007-09-04
Canada
kudos:2
Reviews:
·NorthWest Tel

1 recommendation

reply to PSWired

said by PSWired:

In the future we should be better at mentioning *why* the code prohibits things like this. People are much more likely to find a way to get their problem solved in a compliant manner if they understand the risks, rather than being told that the world will end for some unspecified reason if they don't do as they're told.

The risks here:

1) If one conductor becomes open/disconnected, the remaining conductors can become overloaded.

2) If the conductors are not all the same length, they will not share current evenly, so there is a risk of overloading individual conductors this way as well.


54067323

join:2012-09-25
Tuscaloosa, AL
reply to nunya

said by nunya:

No. It's not allowed temporary or not. Just because you don't get the answer you want, you don't have the right to tell people to piss off. You are a short timer to this site and came here asking for a "how-to" to do something potentially dangerous.

First of all I asked a question about amperage nothing more nothing less and certainly didn't tell anyone to "piss off," furthermore why is it assumed this work falls under the NEC, because it surely doesn't?



54067323

join:2012-09-25
Tuscaloosa, AL
reply to JustBurnt

said by JustBurnt :

What is your definition of "temp setup" in this case?

A couple of weeks and then we blow the ship up.

The power is for HMI lighting for a movie, the original idea was to lower a generator on the bow of the ship and run stingers to where we needed the lighting, but the safety/insurance guy shot that idea down because too many of the walkways are very narrow and he didn’t want anyone tripping on a cable should there be an emergency. So from the bow we ran welding cables down to where the ships generator used to be and then by using the existing wiring paralleled where able to get power to where we needed it.


whizkid3
Premium,MVM
join:2002-02-21
Queens, NY
kudos:9

3 recommendations

reply to 54067323

said by 54067323:

why is it assumed this work falls under the NEC, because it surely doesn't?

Why don't you elaborate? Ask stupid questions and you will get stupid answers that can be completely wrong. Don't blame the posters here for not providing the right answer, when you have not filled them in as to the details. For one, I call BS. If you have to ask such a question, I have to doubt you even have a copy of the NEC; nor have read its 'scope' as to what it covers and what it doesn't.

Have you considered the effects of inductive heating for passing 56 amps through a set of paralleled wires that are not combined with the return conductors? That will be a surprise, I am sure.

The two reasons the NEC does not allow such small conductors to be paralleled (except under certain unusual circumstances) are:
1. It is difficult if not impossible to balance the load in paralleled small conductors, resulting in a dangerous situation where one conductor can overheat resulting in a fire or short circuit.
2. There is no valid reason to parallel small conductors, aside from being too cheap to purchase the right size wire in the first place.

Bob4
Account deleted

join:2012-07-22
New Jersey

2 recommendations

reply to 54067323

You don't have a licensed electrician who knows these answers? You have to ask on an Internet forum?



cdru
Go Colts
Premium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:7
reply to Cho Baka

said by Cho Baka:

Some gasfitters do this.

Natural selection. Only the best survive to do it again.


nunya
Premium,MVM
join:2000-12-23
O Fallon, MO
kudos:12
Reviews:
·Charter
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·surpasshosting

1 edit

3 recommendations

reply to 54067323

I call BS as well. And, BTW, these are your words:
Now if you can advise how many amps I can push down 4 number tens please let me know, if not then pass over this thread.

You're posting in the context of a home improvement forum asking about a maritime electrical question (which you failed to divulge).
You should be consulting with someone familiar with marine electrical systems, specifically 46 CFR Sub-chapter J.

The answer to your question is:
(a) Each cable installation must meet—
(1) Sections 25, except 25.11, of IEEE 45-2002 (incorporated by reference; see 46 CFR 110.10-1 ); or
(2) Cables manufactured to IEC 92-353 must be installed in accordance with IEC 60092-352 (both incorporated by reference; see 46 CFR 110.10-1 ), including clause 8.
(b) Each cable installation made in accordance with clause 8 of IEC 60092-352 must utilize the conductor ampacity values of Table I of IEC 60092-352.

If you don't know what that means, you should hire someone who does.
--
If someone refers to herself / himself as a "guru", they probably aren't.



ropeguru
Premium
join:2001-01-25
Mechanicsville, VA

1 edit
reply to SparkChaser

said by SparkChaser:

The problem with forums like this is (when it comes to electricity or gas or other dangerous "home" projects) , if you have to ask the question, you probably shouldn't be doing it.

No one want to be responsible for someone doing something stupid.
.

Which in my opinion is why forums like this are good. At least people come here and ask FIRST to get proper information.

This is the second thread with this kind of attitude and frankly, if we went with your comment, then this forum should be shut down or locked for licensed professionals only.


54067323

join:2012-09-25
Tuscaloosa, AL
reply to garys_2k

said by garys_2k:

Do you have two circuits that you need to parallel to run a single 56 A load (where the total of four conductors includes two "hots" and two neutrals, EACH being paralleled to two pairs of conductors will carry the total current)? Or, you have four circuits (four hots, four neutrals) that you will parallel to run this load?

i need about 50 amps so what we are doing at the feed end is to take as many number 10 wires as we can prove out (8 or more) and connecting them to a multi-tap which is connected to a 60 amp outlet on a distrobox, then at the other end we are pulling the wires out of junction boxs close to where we need the power chopping lose from their "loads" then using more multi-taps combining them to the inlet of another distrobox and from there the lighting is connected.

the existing wiring is tinned so it's easy to work with but the junction boxes are rusted out rat bottoms that I have had to use a cold chisel and a 5 pound sledge on to get the covers off.

so far we powered up two areas wth no problems.


54067323

join:2012-09-25
Tuscaloosa, AL
reply to whizkid3

said by whizkid3:

2. There is no valid reason to parallel small conductors, aside from being too cheap to purchase the right size wire in the first place.

It's a valid reason when that is all there is to work with and there is no way to replace what is there.


nunya
Premium,MVM
join:2000-12-23
O Fallon, MO
kudos:12
Reviews:
·Charter
·voip.ms
·surpasshosting

1 recommendation

If it's temporary, you bring in PROPERLY SIZED and RATED temporary cables. What you are doing is probably more dangerous at sea than it would be on dry land.
Ever been on a ship that's been on fire? Let me tell you firsthand - it's a whole lot of no fun. Port or not.
--
If someone refers to herself / himself as a "guru", they probably aren't.



ropeguru
Premium
join:2001-01-25
Mechanicsville, VA

said by nunya:

If it's temporary, you bring in PROPERLY SIZED and RATED temporary cables. What you are doing is probably more dangerous at sea than it would be on dry land.
Ever been on a ship that's been on fire? Let me tell you firsthand - it's a whole lot of no fun. Port or not.

While I agree, somehow I think that there probably isn't much left on the ship to burn.

"A couple of weeks and then we blow the ship up."

Bob4
Account deleted

join:2012-07-22
New Jersey
Reviews:
·Optimum Online

2 recommendations

reply to 54067323

said by 54067323:

take as many number 10 wires as we can prove out

the junction boxes are rusted out rat bottoms that I have had to use a cold chisel and a 5 pound sledge on to get the covers off.

So you can't inspect the wires (you're just checking for basic continuity) and have no idea as to their condition, but you know the junction boxes are all rusted. And you're going to be putting 50 amps through them.

What could go wrong?


LazMan
Premium
join:2003-03-26
canada
reply to 54067323

Maybe it's just me, but fudging it with unknown wiring in unknown condition sounds like a lot more work and a lot more dangerous then running an appropriate chunk of Teck90 or some cam-lock cables to where you need to go...

Plus, as was mentioned, you've got to ask the right question to get the right answer...



Thespis
I'm not an actor, but I play one on TV.
Premium
join:2004-08-03
Keller, TX
reply to 54067323

Unfortunately, this kind of approach to wiring is not unusual on movie locations. That's usually nothing compared to the rigging...
In the theatre, we're a little more afraid of burning the place down.
--
Fast. Cheap. Safe.
Pick two...



54067323

join:2012-09-25
Tuscaloosa, AL
reply to nunya

said by nunya:

If it's temporary, you bring in PROPERLY SIZED and RATED temporary cables.

i would love to do that but it is not possible given the constraints I am working under, my idea was to lay in stingers but the "safety" guy shot down that idea, now we are using the ships wiring which he has signed off on.

If you have a better idea on how to rewire a steel ship built in the 50's within three days I would love to here it.

Ever been on a ship that's been on fire? Let me tell you firsthand - it's a whole lot of no fun. Port or not.

Yea about 12 years ago I burnt a cigarette to the waterline, had a little fuel problem in the engine room something lit up and the suppression system went off killing the engines and about a minute later boom.


54067323

join:2012-09-25
Tuscaloosa, AL
reply to ropeguru

said by ropeguru:

While I agree, somehow I think that there probably isn't much left on the ship to burn.

It’s pretty much steel on steel, the wiring is in steel conduit as is every junction box and everything is threadd together.


54067323

join:2012-09-25
Tuscaloosa, AL
reply to Bob4

said by Bob4:

So you can't inspect the wires (you're just checking for basic continuity) and have no idea as to their condition, but you know the junction boxes are all rusted. And you're going to be putting 50 amps through them.

In the boxes we have opened the wiring looks good and megs out just fine.

What could go wrong?

Hopefully nothing