Electrical Primer for Brewers - Page 7 - Home Brew Forums
Home Brew Forums > Home Brewing Beer > Electric Brewing > Electrical Primer for Brewers

Reply
 
Thread Tools
Old 12-17-2009, 01:05 AM   #61
Hermit
Recipes 
 
Nov 2009
Alternate Universe
Posts: 2,281
Liked 72 Times on 61 Posts


Quote:
Originally Posted by rtockst View Post
I just looked at my dryer outlet, and it's a 30A 250V outlet. But I'm not sure if it is the 4 prong or 3 prong w/ no ground. There are 2 flat prongs, 1 prong that is L shaped, and a circle in the middle of the outlet which looks like it might be for a 4th prong. Any ideas? I might just have to turn off my main breaker and have a look inside the outlet
The two flats are hot, the l shaped is neutral. If you look in the 'middle' one you should see a screw unless it is missing. A 4 prong with ground is not laid out that way.

 
Reply With Quote
Old 12-23-2009, 02:45 PM   #62
pickles
 
pickles's Avatar
Recipes 
 
Feb 2008
Columbus
Posts: 2,007
Liked 49 Times on 41 Posts


Can we expect another installment after the holidays/new year? This is really good stuff!

 
Reply With Quote
Old 12-23-2009, 02:59 PM   #63
nelstrodomus
Recipes 
 
Dec 2009
Hartford, CT
Posts: 11

Regarding the dryer outlet, I use one of those. I just use the middle wire as the ground and everything tests out ok.

 
Reply With Quote
Old 12-23-2009, 03:30 PM   #64
Hermit
Recipes 
 
Nov 2009
Alternate Universe
Posts: 2,281
Liked 72 Times on 61 Posts


Quote:
Originally Posted by nelstrodomus View Post
Regarding the dryer outlet, I use one of those. I just use the middle wire as the ground and everything tests out ok.
In theory they are the same thing but reality can be different. WAY to many variables to go into but if the transformer outside your house loses ground then, in theory, your voltages (including neutral) could rise to some seriously dangerous levels. That is why modern code has it as a separate line independent of what the power company provides. When I had my breaker box replaced I was surprised at the effort the guy went through to provide redundant grounds. Also, in theory, even if the neutral is grounded at the transformer, ground potential between your house and the pole can be different.


 
Reply With Quote
Old 12-23-2009, 03:44 PM   #65
nelstrodomus
Recipes 
 
Dec 2009
Hartford, CT
Posts: 11

Will a gfci breaker circumvent the danger you mentioned, or is the danger inherent anyway since you're stating the ability of a safe ground isn't really there?

 
Reply With Quote
Old 12-23-2009, 04:02 PM   #66
Hermit
Recipes 
 
Nov 2009
Alternate Universe
Posts: 2,281
Liked 72 Times on 61 Posts


Quote:
Originally Posted by nelstrodomus View Post
Will a gfci breaker circumvent the danger you mentioned, or is the danger inherent anyway since you're stating the ability of a safe ground isn't really there?
I'm not an engineer, but if you have a faulty "ground" then I'm not sure a ground fault protector would work right. In the case I mentioned the whole system would float above ground potential but maintain their relative values.

I had a friend that worked for a company that the electrical system was designed by a Russian immigrant. Contractors would come in and try and drop a 120 volt outlet off a hot line by running the neutral directly to ground only to find the voltage was NOT what they expected because the system as a whole was not grounded. It "floated".

Bottom line? If your life or safety depend on it, run a reliable ground.

 
Reply With Quote
Old 12-23-2009, 04:11 PM   #67
nelstrodomus
Recipes 
 
Dec 2009
Hartford, CT
Posts: 11

In Soviet Russia, system wires you!

Well, the way I see it, my dryer has been fine for the 20 years it's been on this circuit, so I hope the brewery is. I've also seen many other systems that use the same method that I have....however, these guys haven't updated their blogs in a while...

 
Reply With Quote
Old 12-23-2009, 04:13 PM   #68
CodeRage
Death by Magumba!
HBT_LIFETIMESUPPORTER.png
 
CodeRage's Avatar
Recipes 
 
Aug 2007
Melbourne, Fl
Posts: 2,222
Liked 46 Times on 20 Posts


gfci's are current based, not potential based. The current measured on all legs must be accounted for, so for simplicity's sake lets say 100mA is going out on leg 1 the gfci expects to see approx 100mA on the neutral. If there is only 95mA on the neutral the gfci recognizes that 5mA of current has found an alternate path to ground and trips. (This is the ground fault, not so much there is a problem with the provided ground but current has found an alternate path to ground) This alternate path could be a person getting shocked, a march pump leaking current to the grounded chassis, a loose wire on the control panel making contact to ground, etc etc.

As far as updates go, I am compiling a large document and sets of drawings, The info has become a bit scattered in this thread. I'll start a new thread and put it all in there. Perhaps the wiki too, but that is new territory for me.
__________________
Brutus 20e build | Electrical Primer for Brewers | Auber SYL-2362A2 PID Install & Config
So as I am walking out the door this morning I think to my self:
"self, going to work on Monday is like knowing you're going to get kicked in the nuts. You just don't know when or by who"

BYOBKC Likes This 
Reply With Quote
Old 12-23-2009, 05:16 PM   #69
Hermit
Recipes 
 
Nov 2009
Alternate Universe
Posts: 2,281
Liked 72 Times on 61 Posts


Quote:
Originally Posted by nelstrodomus View Post
In Soviet Russia, system wires you!

Well, the way I see it, my dryer has been fine for the 20 years it's been on this circuit, so I hope the brewery is. I've also seen many other systems that use the same method that I have....however, these guys haven't updated their blogs in a while...
Like I say, there is a difference between practice and theory. It would be an unusual circumstance for the neutral not to be grounded, but I'm not trained nor do have the equipment to do the testing if I was there, let alone across the net. That is why I said, if you life or safety depend on it, ensure you have a good ground.

 
Reply With Quote
Old 12-23-2009, 05:18 PM   #70
Hermit
Recipes 
 
Nov 2009
Alternate Universe
Posts: 2,281
Liked 72 Times on 61 Posts


Quote:
Originally Posted by CodeRage View Post
gfci's are current based, not potential based. The current measured on all legs must be accounted for, so for simplicity's sake lets say 100mA is going out on leg 1 the gfci expects to see approx 100mA on the neutral. If there is only 95mA on the neutral the gfci recognizes that 5mA of current has found an alternate path to ground and trips. (This is the ground fault, not so much there is a problem with the provided ground but current has found an alternate path to ground) This alternate path could be a person getting shocked, a march pump leaking current to the grounded chassis, a loose wire on the control panel making contact to ground, etc etc.

As far as updates go, I am compiling a large document and sets of drawings, The info has become a bit scattered in this thread. I'll start a new thread and put it all in there. Perhaps the wiki too, but that is new territory for me.
So if you 'short' to neutral all current is still accounted for then? Still that is much better than short to laundry tub with you as the conductor I guess.

 
Reply With Quote


Reply
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
DME as primer prrriiide Beginners Beer Brewing Forum 1 10-01-2009 10:15 PM
not enough primer? fightingswede Beginners Beer Brewing Forum 2 06-02-2009 02:39 PM
primer JDengler Beginners Beer Brewing Forum 3 02-22-2009 08:26 AM
how much dme for primer? Spot29er General Techniques 3 01-25-2009 03:08 AM
DME primer McCuckerson General Beer Discussion 7 12-01-2008 10:11 PM


Forum Jump