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#75344 - 02/26/07 05:10 PM Re: Generator Interlock ?
master66 Offline

Registered: 04/18/02
Posts: 260
Loc: Masontown, PA, USA
Used it. Loved it. Highly recommend it.

(uncompensated endorsment)

Work Gear for Electricians and the Trades

Work Gear for Electricians and the Trades
Work Gear for Electricians and the Trades
Arc Flash Clothing, Gloves, KneePads, Tool Belts, Pouches, Tool Carriers, etc. etc....

#75345 - 02/27/07 08:16 PM Re: Generator Interlock ?
LoneGunman Offline

Registered: 10/02/05
Posts: 141
Loc: Florida
Love them, much more flexibility over a small manual transfer switch. Square D and I believe Siemans makes their own now, much less money than the one in the link.

[This message has been edited by LoneGunman (edited 02-27-2007).]

#75346 - 02/28/07 01:14 AM Re: Generator Interlock ?
e57 Offline

Registered: 05/27/03
Posts: 2837
Loc: S.F.,CA USA
Like the add... "Now listed to UL standards" As if they have been selling them forever and just finanaly got the right people to pick up an envelope of a cafe table...

Hotline1 got the back-fed breaker there - I am also wondering if the panel also needs to be listed as transfer equipment.

702.6 Transfer Equipment.
Transfer equipment shall be suitable for the intended use and designed and installed so as to prevent the inadvertent interconnection of normal and alternate sources of supply in any operation of the transfer equipment. Transfer equipment and electric power production systems installed to permit operation in parallel with the normal source shall meet the requirements of Article 705.
Transfer equipment, located on the load side of branch circuit protection, shall be permitted to contain supplementary overcurrent protection having an interrupting rating sufficient for the available fault current that the generator can deliver. The supplementary overcurrent protection devices shall be part of a listed transfer equipment.
Transfer equipment shall be required for all standby systems subject to the provisions of this article and for which an electric-utility supply is either the normal or standby source.

Do they provide you with switch duty breakers?
Mark Heller
"Well - I oughta....." -Jackie Gleason

#75347 - 02/28/07 12:38 PM Re: Generator Interlock ?
Ann Brush Offline

Registered: 12/27/05
Posts: 155
Loc: Ohia
I bought and installed a square D interlock plate for the 200A resi panel in my home. Generator is a 13kW mobile PTO unit plug and cord connected using bus drop cable. Installed a 50A breaker in position 2 and have never looked back - it's great. AHJ passed it on inspection first time without issue. Total cost was $45 plus $11 for the breaker. On the switch rated question, the instructions specifically say to turn off all individual breakers, energise the 50A back-fed breaker once the PTO is interconnected and running, and THEN energise the individual branch circuits you want to use (this was the major motivation for me to use this route - I wanted to control which circuits to use). So if you are following instructions the breaker is not used to switch the load. In any case if it's rated at 50A why couldn't you use it for emergency switching (not like it's being used often), it's rated for 50A.

#75348 - 02/28/07 07:19 PM Re: Generator Interlock ?
NJ_WVUGrad Offline

Registered: 01/17/06
Posts: 48
Loc: Neptune, NJ, USA
In my experiences with numerous Wireless (Cellular Telephone, E911, Microwave backhaul) sites. This seams to be a preferred design for emergency power provisioning.

Especially when pulling up a trailer mounted genset.

It also cuts down on points of failure and can be considered as a good example of KISS "keep it simple stupid" design.

#162447 - 04/19/07 07:55 AM Re: Generator Interlock ? [Re: NJ_WVUGrad]
Interlock_Kit Offline
New Member

Registered: 04/19/07
Posts: 2
Loc: Richmond, VA
Thanks for the support from most of you in this forum.

As the manufacturer of the Interlock Kit we are determined to remedy all the questions asked in the market about our product.

We assure that our product is safe, NEC code compliant, and Listed to UL standards.

GO TO to see the real advantage over the traditional installations of transfer switches.

On that note, I wanted to comment on the listing of the product and some concerns that have been raised.

Our product is considered an Accessory to a panel. Meaning that we do not fit in the UL area of transfer switches. Since the interlock kit does NOT possess any electrical components nor does it actually transfer power from the main to the generator we are considered accessories.

The user or homeowner is actually the transfering of the power solely putting the task of actually turning off one breaker and then turning on the other to feed the panel. So in essence the user of the interlock kit is actually the Transferer of power.


#162467 - 04/19/07 12:43 PM Re: Generator Interlock ? [Re: Interlock_Kit]
ghost307 Offline

Registered: 05/09/05
Posts: 852
Loc: Chicago Illinois USA
Gee...when did we start accepting commercials on this forum??

...and it's not the equipment's job to transfer power; the guy flipping the switch is technically "the transferer of power".

Now it sounds even more like snake oil.

#162472 - 04/19/07 01:02 PM Re: Generator Interlock ? [Re: ghost307]
gfretwell Offline


Registered: 07/20/04
Posts: 8930
Loc: Estero,Fl,usa
I think the principle of interlocking the breakers so you can't back feed the grid is sound. You would have evaluate each product to decide whether you believe the execution is done properly. I think if it is sold by the OEM it should be OK. For a residential application where automatic switching is not required this may be the easiest option. Just be sure the O/C device selected for the generator side is sized properly and the actual installation of the interlock is done per manufacturer spec. You could still run into a 110.3(B) problem if the panel manufacturer says a 3d party model is not equal to their device (like the challenger breaker problem). I suppose when 3d party interlocks start competing with the panel manufacturer's model in any significant way we will hear about this one.
Greg Fretwell

#162473 - 04/19/07 01:07 PM Re: Generator Interlock ? [Re: ghost307]
Alan Belson Offline

Registered: 03/23/05
Posts: 1801
Loc: Mayenne N. France
Seems fair to me that Ryan replied. Questions were asked about the product and the answers came back from the company. It's a simple mechanical interlock, period. You can't criticise products just because they don't cater 100% against Darwin Award candidates. I could cook my head in the microwave if I disabled the door microswitch with a screwdriver.
Wood work but can't!

#162477 - 04/19/07 03:34 PM Re: Generator Interlock ? [Re: Alan Belson]
Roger Offline

Registered: 05/18/02
Posts: 1779
Loc: N.C.
Ghost, you are right, we don't accept or allow commercials in the forums but, in this case I don't think Ryan's post is a commercial.

The thread was started by a member two months ago and was specifically asking about this product, the OP even included a link to the product.


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