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hammerslammer
08-20-2007, 08:12 PM
I'm moving my water heater and I guess i will need a disconnect at the new location. So i'm thinking a metal box with a double pole single throw 30 amp switch will do. Am I close?? Thanks!!

Speedy Petey
08-21-2007, 04:00 AM
NO! Expensive and more work.
Use a plain 60A non-fused "pull-out" type disconnect. The type used for A/C installations. They are fully self contained and run about 10 bucks.

jwelectric
08-21-2007, 04:19 AM
Or

Use a lock out on the breaket for about $2

Chris75
08-21-2007, 01:56 PM
Or

Maybe he's moving the heater next to the panel so he would not even need a separate disconnect... ;)

hammerslammer
08-21-2007, 02:16 PM
Or

Maybe he's moving the heater next to the panel so he would not even need a separate disconnect... ;)

No it will be a good ways from the panel. I was checking out the disconnects that Speedy mentioned at the depot and they look like a pretty good deal . They had a 30 amp and a 60. I guess the 60 is recomended because the breaker will be 30a.?? Thanks for the replys.

jadnashua
08-21-2007, 04:48 PM
By definition, it would seem that if you have a 30A breaker, the disconnect would need to be rated for at least 30A; I think the 60A isn't needed. If I understand this, it's sort of like sizing the wiring, you can't use less than 12g on a 20A circuit, but 10g would be overkill...why spend the money unless you have a very long run.

Chris75
08-21-2007, 05:29 PM
By definition, it would seem that if you have a 30A breaker, the disconnect would need to be rated for at least 30A; I think the 60A isn't needed. If I understand this, it's sort of like sizing the wiring, you can't use less than 12g on a 20A circuit, but 10g would be overkill...why spend the money unless you have a very long run.


60 amp disconnect is a pretty common thing you will find in a home center, and cheaper than a 30 amp...

jadnashua
08-21-2007, 05:53 PM
Sounds like a plan, then. I was just figuring the 30A would be cheaper, and was all that was required. Must be a volume thing...

Chris75
08-21-2007, 06:08 PM
Sounds like a plan, then. I was just figuring the 30A would be cheaper, and was all that was required. Must be a volume thing...


Yep... Not really even sure why they make a 30a...

cwhyu2
08-21-2007, 06:51 PM
I would run 10/3wground from your main panel ,install new 30 amp brkr
unless you need to upgrade your service and panel.

Speedy Petey
08-21-2007, 07:06 PM
I would run 10/3wground from your main panel ,install new 30 amp brkr
unless you need to upgrade your service and panel.I'm not sure what this has to do with the original question about needing a disconnect.

Also, 10/3 is NOT needed for a water heater. 10/2 is perfect and typical for this installation.
Using 10/3 is basically wasteful.

hammerslammer
08-30-2007, 04:43 AM
I'm not sure what this has to do with the original question about needing a disconnect.

Also, 10/3 is NOT needed for a water heater. 10/2 is perfect and typical for this installation.
Using 10/3 is basically wasteful.

How about the idea that (smart) water heaters of the future might requie a neutral?? Just remembering the days when we ran 10-2 for dryers....

I did price out a roll of 10-2 and 10-3 the other day. More than a water heater.:(

Bob NH
08-30-2007, 06:03 AM
How about the idea that (smart) water heaters of the future might requie a neutral?? Just remembering the days when we ran 10-2 for dryers....

I did price out a roll of 10-2 and 10-3 the other day. More than a water heater.:(

Anyone that builds a "smart" water heater that requires a neutral or a 120 Volt circuit has proved that he is not smart enough to build a "smart" water heater.

hammerslammer
08-30-2007, 06:15 AM
Anyone that builds a "smart" water heater that requires a neutral or a 120 Volt circuit has proved that he is not smart enough to build a "smart" water heater.

Right. I was just wondering if it might be "smart" to run a nuetral...

22 years ago my plumbers tried to talk me out of lowboy gas heaters in the crawlers. I was too "smart" to listen to them.:rolleyes: I'd like to get this chit right in case i last another 22.

Chris75
08-30-2007, 01:32 PM
Just remembering the days when we ran 10-2 for dryers....



10-2 was never allowed for a dryer...need a insulated neutral.... You were allowed to use the neutral as a ground, but not the other way around...

Speedy Petey
08-30-2007, 01:43 PM
As I scroll down I see Chris beat me to the reply.
I see old 10/2 all the times used for dryers. This was NEVER code legal NOR was it ever safe!!!!
Folks who used 10/2 for dryers simply did not know, or care to know, the code.

hammerslammer
09-07-2007, 07:28 PM
As I scroll down I see Chris beat me to the reply.
I see old 10/2 all the times used for dryers. This was NEVER code legal NOR was it ever safe!!!!
Folks who used 10/2 for dryers simply did not know, or care to know, the code.

Wow what a shock for me. I guess i've seen it to and assumed that it was allowed in the past. I have some 10-2 to tear out on my oun house but fortunately it was for a future 2nd laundry room and was never used. Thanks,:o

hj
09-07-2007, 08:01 PM
10/2 w grd was the standard for decades before the 4 terminal plugs were adopted. The difference between a dryer and a water heater is that the dryer has a 120 volt control and motor circuit that needs the neutral, whether it is a 10/2 or 10/3 w ground. And they were always "safe" because the neutral and shell were bonded together.

Speedy Petey
09-08-2007, 04:42 AM
10/2 w grd was the standard for decades before the 4 terminal plugs were adopted.ABSOLUTELY NOT!
It was NEVER the "standard". At least by anyone who knew what they were doing.
As has been said now several times, 10/2 has NO neutral in a 120/240v application. This means the bare ground carried current. This was never allowed and was never safe.
The ONLY exception was when SEU cable was used. This is the service cable that has two conductors with the grounded (NOT grounding) conductor wrapped around them. This exception is now long gone as well.




......whether it is a 10/2 or 10/3 w ground. And they were always "safe" because the neutral and shell were bonded together.Which is the reason for needing an insulated neutral as opposed to a bare ground. Any kind of 10/3 was safe in the past. 10/2 was NOT.

hj
09-08-2007, 05:31 PM
In that case there were a "jillion" electricians who did not know what they were doing, including the one that wired my new house 6 years ago, to match my 3 prong male plug. As I said, it was standard for decades. You never saw a 4 prong plug for a dryer until the last decade at the earliest. Maybe you are too new in the business to go back that far.

Speedy Petey
09-08-2007, 07:22 PM
In that case there were a "jillion" electricians who did not know what they were doing, including the one that wired my new house 6 years ago, to match my 3 prong male plug. Yes. That is exactly right.
If the electrician who wired your house wired the dryer circuit to match the plug then I'd love to see what else he did there. You match the plug to the receptacle, NOT the other way around. And the receptacle MUST be wired to code.
If he installed a 3-prong dryer circuit and receptacle six years ago he obviously did NOT know what he was doing. That or he simply didn't care. The neutral/ground bond exception was dropped in 1996. Four prong receptacles with a separate ground and neutral have been mandatory since then.
If he EVER wired a dryer with 10/2, ESPECIALLY as soon as six years ago, I'd love to know his name so I can report him to the licensing bureau.



As I said, it was standard for decades. You are misunderstanding what I am saying. I am NOT saying 3-prong dryer receptacles were not legal or safe. That WAS the standard for MANY years. I see them all the time. Only I mostly see them wired with 10/3 without ground or SEU cable. The old, yet CORRECT way.




You never saw a 4 prong plug for a dryer until the last decade at the earliest.Not true. 4-prong receptacles have always been code for dryers and ranges in mobile homes.





Maybe you are too new in the business to go back that far.Nice try.

Chris75
09-08-2007, 08:01 PM
I don't think people know the difference between 10-2 and 10-3, there is some obvious confusion about the subject... hence the 3-wire and 4-wire dryer/receptacle comments being made...

The picture below is 10-2 NM, notice that if this was used for a dryer, you would be forced to use the bare copper wire for the neutral, this is the code violation, the neutral conductor MUST be insulated... Hence the use for 10-3 which would contain a blk,red,white, and bare copper conductor...
http://www.southwire.com/productCatalog/images/thumbs/nm.jpg



Here are some examples of the 1996 code change dealing with 3-wire and 4-wire receptacles...

Three Wire Hook-up, Notice the Grounded (neutral) is also bonded to the frame of the dryer, so the neutral was also the ground.
http://www.american-appliance.com/catalog/images/terminalblock.jpg

Four Wire Hook-up, Notice the Grounded (neutral) and Grounding (ground) conductors are isolated...
http://www.american-appliance.com/catalog/images/4prongcord_small.jpg

frenchelectrican
09-08-2007, 10:55 PM
I don't think people know the difference between 10-2 and 10-3, there is some obvious confusion about the subject... hence the 3-wire and 4-wire dryer/receptacle comments being made...

The picture below is 10-2 NM, notice that if this was used for a dryer, you would be forced to use the bare copper wire for the neutral, this is the code violation, the neutral conductor MUST be insulated... Hence the use for 10-3 which would contain a blk,red,white, and bare copper conductor...
http://www.southwire.com/productCatalog/images/thumbs/nm.jpg



Here are some examples of the 1996 code change dealing with 3-wire and 4-wire receptacles...

Three Wire Hook-up, Notice the Grounded (neutral) is also bonded to the frame of the dryer, so the neutral was also the ground.
http://www.american-appliance.com/catalog/images/terminalblock.jpg

Four Wire Hook-up, Notice the Grounded (neutral) and Grounding (ground) conductors are isolated...
http://www.american-appliance.com/catalog/images/4prongcord_small.jpg

chris please look at the 4 wire cord connector on the dryer there is two code voliations there allready

1] where is the " strain relef aka NM clamp "

2] did you see where the greenwire still on the netural wire

Merci, Marc

frenchelectrican
09-08-2007, 11:11 PM
You never saw a 4 prong plug for a dryer until the last decade at the earliest. Maybe you are too new in the business to go back that far.


HJ: the code was in effect for Mobile homes for range and dryers it was enforced way back late 50's- early 60's

the same with city of Chicago they have that code way before the NEC change that code as well

HJ , you may want to ask any old electrician or find the older NEC code book that go back in history and find how far it went back.

if you think the NEC is tough try this the european electrical code is very insane [ i allready got master from France so i am very famuiar with their insane code and connections that make your mind spin ]

Merci , Marc

Speedy Petey
09-09-2007, 03:28 AM
2] did you see where the greenwire still on the netural wireMarc, this is a pretty common procedure. That green is the one from the wiring harness that is bonded to the neutral.
What's nice about doing it that way is if they ever move to a home with an older 3-wire receptacle it can be converted back without any trouble.

sbrn33
09-09-2007, 01:08 PM
I am assuming that HJ doesn't know the difference between 10-2 and 10-3 and definitively doesn't know the difference between neutral and ground or understand that neutral is a current carrying conductor in most cases. This si why it must be insulated.
Probably shouldn't be giving advice on an electrical forum.

Chris75
09-09-2007, 02:07 PM
chris please look at the 4 wire cord connector on the dryer there is two code voliations there allready

1] where is the " strain relef aka NM clamp "

2] did you see where the greenwire still on the netural wire

Merci, Marc

What do you want from a picture off the net? perfect? :D

Alectrician
09-18-2007, 11:01 PM
The ONLY exception was when SEU cable was used. This is the service cable that has two conductors with the grounded (NOT grounding) conductor wrapped around them.


Semantics. #10 SE = 10-2.

2 #10 hots and a ground.

Speedy Petey
09-19-2007, 03:39 AM
Semantics. #10 SE = 10-2.

2 #10 hots and a ground.First of all, bull! #10 SEU would NOT be 10/2. It would be #10SEU, period. The conductor identification would be "3c 10".
#2 SEU would be "2c 2, 1c 4". Two conductors #2 and one conductor #4.

SER is rated the same way just a bit different. #2AL SER would be "2-2-2-4".

Once again, #10 SE does NOT = 10-2.

ked
09-21-2007, 07:27 AM
In my county, 10-3 w G is now required for dryers, with a four prong cord.

dannygd3
04-07-2012, 02:02 AM
i hope those who have a 10-2 ran for their dryer wear their shoes while doing laundry! the fact that the ground and neutral have to be bonded at the main doesn't mean they're interchangeable, the ground wire can't act as the neutral. the least of the worries here is that the NEC states that the neutral must be identified by having stripes in the insulation, white or gray colored insulation (unless #6? i think? or larger then they have to be marked with phase tape) correct me if i'm wrong there's always something to learn

dannygd3
04-07-2012, 02:09 AM
just because it's common doesn't mean it's right...the green from the dryer cord should be bonded to the dryer not to the neutral. go nuts and bond the neutral and ground as many times as you want at/before the main there's nothing in the code against that but after the main bonding them is against code with the exception of at a transformer which shouldn't really come into play in residential.

dannygd3
04-07-2012, 02:14 AM
i've been doing this a while, not forever so i don't know what used to be allowed but the only time i've seen the 3 prong dryer receptacles is on remodel type jobs where the electrical installation was done before pulling a ground wire was the norm

jimbo
04-07-2012, 08:11 AM
i've been doing this a while, not forever so i don't know what used to be allowed but the only time i've seen the 3 prong dryer receptacles is on remodel type jobs where the electrical installation was done before pulling a ground wire was the norm

That is correct, danny. The elect code changed sometime late '80s early '90s, requiring 4 prong for stoves and dryers . One of the electric gurus will tell us the exact year.

As far as I know, if the three prong is in place, you can still use it as long as you don't move or remodel. Installers need to understand the difference, because the new appliance may come "rigged" for 4 wire cord, so you have to rearrange the ground/neutral connections on the block per the install manual

hj
04-07-2012, 09:19 AM
IF they build a "smart water heater" it will either be all 240, or it will have a cord and need a 120 receptacle near the heater.

Hackney plumbing
04-07-2012, 09:38 AM
I think all electric water heaters should simply plug in just like a dryer.

hj
04-07-2012, 02:17 PM
Again we are talking semantics, because the "neutral" in the SEU cable is carrying current, but NOT insulated by anything other than the sheathing. When the electricians wired my 3 prong receptacle, they did NOT even know what kind of cord my dryer had.