Generator To Mains - Electrical - Page 2 - DIY Chatroom Home Improvement Forum
Advertisement


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools
Display Modes
Old 02-14-2010, 07:16 PM   #16
Member
 
Join Date: Jan 2008
Location: Alabama
Posts: 608
Rewards Points: 500
Default


Quote:
Originally Posted by J. V. View Post
Don't be silly. I am a licensed electrical contractor and master. I have installed several interlock kits for customers and have one in my own house. I would rather sell them an expensive ATS, but I try to be as honest as I can and give them this option.
The interlock is an inexpensive and safe alternative to an ATS. But it's not for everyone.
Nice to know. I was just recently doing a touch of research on generators and how you connect them to your home wiring. I was following some links others had suggested and just wasn't finding anything cheap (nothing less than about $300).
HooKooDooKu is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 02-14-2010, 09:22 PM   #17
UAW SKILLED TRADES
 
Stubbie's Avatar
 
Join Date: Jan 2007
Location: Kansas
Posts: 5,341
Rewards Points: 2,652
Default


It would be rare even for an interlock installation to come out less than 300$ do it yourself. You will have around 100 to 150 bucks for factory or aftermarket interlock kit. Then wire, power inlet and accessory hardware. A generator breaker and likely tandem breakers to create space if panel is full. etc.... I also provide laminated instructions on using the generator and returning to utility power and a laminated line graphic showing what the installation looks like. These are placed at the loadcenter. I also like to provide the power cord. One of my biggest eye winches is when I see a homemade cord the customer proposes to use with his generator. I generally like 10 to 20 foot cord sets from reliance controls. I also like their power inlets.

Custom made interlocks will run around 250 to 300 bucks if made from aluminum stock.
__________________
" One nice thing about the NEC articles ... you have lots of choices"

Stubbie

Last edited by Stubbie; 02-14-2010 at 09:24 PM.
Stubbie is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 05-07-2010, 04:12 PM   #18
Member
 
Join Date: May 2010
Posts: 95
Rewards Points: 75
Default


Quote:
Originally Posted by Scuba_Dave View Post
What you are considering doing is illegal & dangerous

You need a panel/breaker setup with a gen lockout
OR
A transfer setup

Most service feeds are setup so that the main breaker will kill all power
But not ALL are setup this way

You will be held responsible if your connection hurts or kills a lineman working on the wires
Your power back feeds the transformer on the pole & then steps up your voltage to lethal amounts

Your main breaker only disconnects the Hots, not the neutral
You bring up a good point about only disconnecting the hots, not the neutral. So, if the hots are disconnected, how can this pose a threat if the service is disconnected, and the generator and cable are wired properly.

If the breaker only disconnects the hots and not the neutral, what difference would an interlock kit make? The physical connection between the generator and the panel is the same as if there weren't an interlock plate, it just prevents someone from accidentally having both on at the same time. So, I'm a bit confused as to why there would be such a danger without an interlock (assuming the breakers are in the proper position).

Homer
homerb is offline   Reply With Quote
Sponsored Links
Advertisement
 
Old 05-07-2010, 04:56 PM   #19
Inspector/Instructor
 
codeone's Avatar
 
Join Date: Dec 2009
Location: NC
Posts: 369
Rewards Points: 250
Default


Quote:
Originally Posted by homerb View Post
You bring up a good point about only disconnecting the hots, not the neutral. So, if the hots are disconnected, how can this pose a threat if the service is disconnected, and the generator and cable are wired properly.

If the breaker only disconnects the hots and not the neutral, what difference would an interlock kit make? The physical connection between the generator and the panel is the same as if there weren't an interlock plate, it just prevents someone from accidentally having both on at the same time. So, I'm a bit confused as to why there would be such a danger without an interlock (assuming the breakers are in the proper position).

Homer
Have you ever accidentally knocked a breaker on or off?

Its so accidents dont happen!

Or in a moment of confusion you cannot accidentally turn both on.
It forces you to do it right.
codeone is offline   Reply With Quote
Old 05-07-2010, 05:08 PM   #20
DIYer
 
Join Date: Oct 2008
Location: Virginia
Posts: 910
Rewards Points: 500
Default


Disconnecting the hots is sufficient.
Gigs is offline   Reply With Quote
Old 05-07-2010, 06:41 PM   #21
Member
 
Join Date: May 2010
Posts: 95
Rewards Points: 75
Default


Quote:
Originally Posted by codeone View Post
Have you ever accidentally knocked a breaker on or off?

Its so accidents dont happen!

Or in a moment of confusion you cannot accidentally turn both on.
It forces you to do it right.
You're right, accidents do happen, especially during an emergency situation like a storm and in the dark during a panic.

I understand the purpose and necessity of an interlock.

But I think it's important to explain (for the purpose of understanding home wiring, rather than being afraid of what you don't know) that the physical wiring configuration between a generator to the panel and the panel to the grid (off) is the same whether you have a: 1) double male extension cord plugged into a 40a 240v outlet with the main breaker off. vs. 2) a male to female extension cord plugged into a 40a 240v inlet box with a interlock in "generator mode". In both cases, each hot leg and the neutral plugged into the panel from the generator, and each hot leg is disconnected from the grid while the neutral remains connected.

We all know the dangers, risks, and legal implications of the "improper way". But it would be wrong to say that the configuration of the "wrong way" is different from the "right way" besides certain safeguards such as: 1) the proper capacity to feed a panel from a generator without overloading 2) female plugs from the generator so you don't shock yourself, and above all, 3) a way of preventing both utility and generator circuits from feeding the panel at the same time.

If anyone can tell me how they might be differ beyond these safeguards, please explain. Are there any systems that also disconnect the neutral? Do the multi circuit transfer switches only disconect the hots from each individual circuit? Or do they switch both the hot and neutral from the utility to generator input?

I am not trying to make an argument about whether or not these safeguards should be in place (we know they should), just trying to demonstrate the concepts taking place (and understand it better myself so I can make a better decision about what I will be installing).

I think people are spending way more money than they need to be spending on extra panels, duplicate breakers for each circuit, etc. because they don't understand how it all works and they are afraid of it.

Homer
homerb is offline   Reply With Quote
Old 05-07-2010, 07:08 PM   #22
Member
 
Join Date: Jan 2009
Location: South of Boston, MA
Posts: 17,248
Rewards Points: 2,000
Default


Multi-circuit transfers switches only switch the hot, not the neutral
I have one & will be getting rid of it in favor of an interlock kit

I never understood the true danger of backfeeding the main electric lines until someone explained that the transformer works in both directions
It steps down for house voltage
But in reverse it will take the Gen voltage & step it up



Scuba_Dave is offline   Reply With Quote
The Following User Says Thank You to Scuba_Dave For This Useful Post:
homerb (05-07-2010)
Old 05-07-2010, 07:57 PM   #23
Member
 
Join Date: May 2010
Posts: 95
Rewards Points: 75
Default


Quote:
Originally Posted by Scuba_Dave View Post
Multi-circuit transfers switches only switch the hot, not the neutral
I have one & will be getting rid of it in favor of an interlock kit

I never understood the true danger of backfeeding the main electric lines until someone explained that the transformer works in both directions
It steps down for house voltage
But in reverse it will take the Gen voltage & step it up
Good point about the transformers. Even without transformers stepping up the voltage, there's a danger for linemen if a generator is feeding into the utility.

Is there any danger of a circuit breaker failing (even with an interlock) in the off position? Do you need a special type of breaker for the utility side when used in conjunction with an interlock?

Why are you switching to an interlock from your "old" transfer switch? What kind and size is it? You lookin to sell it?

I'm debating on whether or not to install an interlock, or a 10 circuit 50 amp transfer switch in my siemens sub panel in the garage. The sub panel has 2 240V breakers for the dryer and water heater, and 8 120v breakers with two switches on each of them for the various rooms in the house. I'm not even sure if the 10 circuit switch will work, I might only be able to use it with half of those breakers in the sub panel. I'll be powering it with a generac 7500w cont 13,500w surge generator that has a NEMA 14-50 outlet on it.

It's crunch time for me. I live in Florida and hurricane season is less than a month away. Last few years were too calm. I don't want to get stuck without a transfer switch with the power out...
homerb is offline   Reply With Quote
Old 05-07-2010, 08:16 PM   #24
Member
 
Join Date: Jan 2009
Location: South of Boston, MA
Posts: 17,248
Rewards Points: 2,000
Default


My transfer switch will only control 6 circuits
With an interlock kit I can power anything I want in my house - if I choose to put an interlock on the main 200a panel

Or anything connected to the 100a sub - which I wll probably do instead
In rewiring my house I moved circuits that I wanted to power with a generator to the 100a sub
Freezer, fridge, main lighting circuit, smokes, kitchen circuit, furnace pump
I still have 9 spaces open on the 100a sub

I won't be selling the GenPac transfer switch until I have the interlock installed
I suppose I could fashion a connection & use it to power some circuits on the 200a panel
But not really needed



Scuba_Dave is offline   Reply With Quote
Old 05-07-2010, 08:18 PM   #25
Inspector/Instructor
 
codeone's Avatar
 
Join Date: Dec 2009
Location: NC
Posts: 369
Rewards Points: 250
Default


When you have the Neutral unswitched it is a derived system.
When you switch the Neutral it is a seperately derived system.

Either system can be dangerous if not installed properly.

The differences is in the way the grounding electrodes and the main bonding jumpers are installed.

When switching the neutrals if your bonding jumper is not installed at the proper place the generator could electrocute you.
codeone is offline   Reply With Quote
Sponsored Links
Advertisement
 
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Summer House Electrics stu_bill Electrical 9 07-31-2008 10:17 AM
Air in mains water [email protected] Plumbing 1 01-26-2008 02:40 PM
80 leds for led light. can i run to 230v mains donnol1983 Electrical 8 12-27-2007 06:23 PM
3 way switch and burnt mains tke402 Electrical 7 10-24-2007 09:18 AM
replacing mains wire elementx440 Electrical 3 05-09-2007 08:29 PM




Top of Page | View New Posts