Generator Interlock Kits

liquidtite

Senior Member
Do insurance companies except interlock installations -are these interlocks nec compliant I can't find any article that covers this ?
 

ceb58

Senior Member
Do insurance companies except interlock installations -are these interlocks nec compliant I can't find any article that covers this ?
702.5 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.
This is part of 702.5. I see the interlock as "suitable for the intended use" and it "prevents inadvertent interconnection".
 

GoldDigger

Moderator
Staff member
This is part of 702.5. I see the interlock as "suitable for the intended use" and it "prevents inadvertent interconnection".
See this thread.

Panelboards are listed under UL 67. Modifications, including field modifications, to those would be covered by that UL standard. And since the panelboard is required by NEC to be UL listed, one can argue that any modification must maintain that listing.

Many interlock kits are designed specifically for particular panel brands and configurations. And some if not all assert that they are listed under UL 67.
Unfortunately I cannot afford a copy of UL 67, so I can't say more about what it allows in the way of interlock kits, especially third party. Kits from the individual manufacturer are presumably OK.

Here is one example of third-party interlocks, with words about UL 67.
 
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tom baker

First Chief Moderator
Staff member
These interlocks are commonly installed around here and are accepted by the AHJs, they are identified for the purpose.
 

iwire

Moderator
Staff member
See this thread.

Panelboards are listed under UL 67. Modifications, including field modifications, to those would be covered by that UL standard. And since the panelboard is required by NEC to be UL listed, one can argue that any modification must maintain that listing.

Many interlock kits are designed specifically for particular panel brands and configurations. And some if not all assert that they are listed under UL 67.
Unfortunately I cannot afford a copy of UL 67, so I can't say more about what it allows in the way of interlock kits, especially third party. Kits from the individual manufacturer are presumably OK.

Here is one example of third-party interlocks, with words about UL 67.

Lets not forget that ULs postion is that it is up to the AHJ to determine if feild modifications have changed things enough to warrant refusing the installation or having a UL feild evaluation done.
 

infinity

Moderator
Staff member
I just wonder why you would go through all of this trouble to manufacture a product ($$$ I would guess) and not have it listed so that there is no question of it's suitability from the end user. Their website states that it's tested on UL67 listed panelboards and makes no mention of the actual product listing. I e-mailed them some time ago asking for clarification but they never responded. :roll:

Tested for use with UL 67 Listed Panelboards
Ref. Wyle Laboratories Test Report T52431-01


Wyle is a Nationally Recognized Testing Laboratory authorized by OSHA for UL standard
67 and recognized by all 50 US States

 

jumper

Senior Member
One reason for a slow reply might be that Wyle lost their NRTL status IIRC.

The interlock kit makers probably are not happy with that and may be reluctant to talk about it.
 

goldstar

Senior Member
The vast majority of EI's in northern NJ are not accepting these interlock kits. IMHO, they are a safety device, they work and their intended use is obvious. It is far safer than back-feeding a house through an AC disconnect. However, the EI's reasons for non-acceptance include :
  • They are not UL listed for the specific panel
  • Making holes in the panel cover may weaken the cover
  • If you remove the panel cover it is no longer a safe situation (like I would have a reason to remove the panel cover during a power outage as opposed to any other time)
  • Use of these devices may require the use of piggy-back breakers in fully loaded panels where these breakers may not be acceptable for use.
Unless the State intervenes and accepts these interlock kits as approved safety devices EI's will continue to cover their butts by not accepting them.
 

eHunter

Senior Member
The vast majority of EI's in northern NJ are not accepting these interlock kits. IMHO, they are a safety device, they work and their intended use is obvious. It is far safer than back-feeding a house through an AC disconnect. However, the EI's reasons for non-acceptance include :
  • They are not UL listed for the specific panel
  • Making holes in the panel cover may weaken the cover
  • If you remove the panel cover it is no longer a safe situation (like I would have a reason to remove the panel cover during a power outage as opposed to any other time)
  • Use of these devices may require the use of piggy-back breakers in fully loaded panels where these breakers may not be acceptable for use.
Unless the State intervenes and accepts these interlock kits as approved safety devices EI's will continue to cover their butts by not accepting them.
I believe both of these kits from Square D are UL listed.
QOCRBGK1
PK4DTIM4LA
http://static.schneider-electric.us/docs/Electrical Distribution/Load Centers/Accessories-QO-LK-PK-QO-QON/1100HO9902.pdf

Would the EI still reject them if used on the panel they were designed for?
 
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Strathead

Senior Member
Kirk Key has been in business since the 1930's Installation requires modification of the panels. They have been accepted by Govt installations, schools, industrial etc. for years. So, I ask, are they UL listed for each and every panel they are installed on? I feel that an AHJ that denies the OP's device is being disingenuous. It is a cost effective, and extremely, operationally effective piece of equipment. I would appeal any AHJ's denial to a higher authority. Common sense disputes all of the arguments presented from the AHJ here. I am pretty sure that the local AHJ would approve of this before they would approve of my money saving method of hooking up my portable generator on the off chance my power goes out ;);)!
 

goldstar

Senior Member
I believe both of these kits from Square D are UL listed.
QOCRBGK1
PK4DTIM4LA
http://static.schneider-electric.us/docs/Electrical Distribution/Load Centers/Accessories-QO-LK-PK-QO-QON/1100HO9902.pdf

Would the EI still reject them if used on the panel they were designed for?
The units you've shown are retaining kits for back-fed breakers if you're converting a main lug panel to a main breaker panel. These are not used for portable generator installs. They have no way of interlocking with a main breaker unless I'm missing something.
 

goldstar

Senior Member
Kirk Key has been in business since the 1930's Installation requires modification of the panels. They have been accepted by Govt installations, schools, industrial etc. for years. So, I ask, are they UL listed for each and every panel they are installed on? I feel that an AHJ that denies the OP's device is being disingenuous. It is a cost effective, and extremely, operationally effective piece of equipment. I would appeal any AHJ's denial to a higher authority. Common sense disputes all of the arguments presented from the AHJ here. I am pretty sure that the local AHJ would approve of this before they would approve of my money saving method of hooking up my portable generator on the off chance my power goes out ;);)!
I'm with you 100%. But if they're not accepted - they're not accepted. You can appeal and yell and scream all you want but it won't pass (in many areas).:rant:
 

eHunter

Senior Member
The units you've shown are retaining kits for back-fed breakers if you're converting a main lug panel to a main breaker panel. These are not used for portable generator installs. They have no way of interlocking with a main breaker unless I'm missing something.
Sorry about that. I plead guilty to operating without the influence of my morning caffeine.
Try these instead.
Page 17
http://static.schneider-electric.us/docs/Electrical Distribution/Load Centers/1100CT0501.pdf
Page 13
http://static.schneider-electric.us/docs/Electrical Distribution/Load Centers/0110PL9401.pdf
 

kwired

Electron manager
The units you've shown are retaining kits for back-fed breakers if you're converting a main lug panel to a main breaker panel. These are not used for portable generator installs. They have no way of interlocking with a main breaker unless I'm missing something.
The catalog numbers he mentioned are interlock kits, the image in the link is not for either number he gave us.



I think this is a little like the classified vs listed breaker issue. None of the panel manufacturers want to accept any accessory they did not make as being something that can be installed in their equipment.

Equipment is listed as is when it leaves the manufacturer. Drill a mounting hole, punch a cable or raceway entry and we no longer have the same thing that left the factory.
 

goldstar

Senior Member
Again, from a personal point of view, I have no problem with any of these kits. However, irrespective of whether they're manufactured by the panel maunfacturer or not, if they don't bear a UL label it gives the EI a reason to not approve their use. I believe they're considered an "appliance" and getting a UL listing may not be possible or practical. Don't forget, submitting something to UL doesn't just cost a mere $25.00. In order for a manufacturer to submit an item it has to be worth their while.
 

mjf

Senior Member
Look around some, the manufacturers are not stupid. They are making interlock kits. Here's a few examples:

GE - http://www.geindustrial.com/cwc/Dispatcher?REQUEST=PRODUCTS&pnlid=7&famid=16&catid=9987&id=gik

Square D - http://static.schneider-electric.us/docs/Electrical Distribution/Load Centers/Accessories-QO-LK-PK-QO-QON/40273-809-02.pdf

Cutler Hammer sells a whole new dead front with the interlock factory installed.

My AHJ accepts them as long as they are UL listed.

I guess if you're trying to find one for an older panel it could be more problematical, but I would check with the manufacturer before I looked elsewhere
 

kwired

Electron manager
Again, from a personal point of view, I have no problem with any of these kits. However, irrespective of whether they're manufactured by the panel maunfacturer or not, if they don't bear a UL label it gives the EI a reason to not approve their use. I believe they're considered an "appliance" and getting a UL listing may not be possible or practical. Don't forget, submitting something to UL doesn't just cost a mere $25.00. In order for a manufacturer to submit an item it has to be worth their while.
I understand what you are saying but "appliance" maybe was the wrong choice of words.
 

eHunter

Senior Member
Just a followup on the Square D QO generator interlock kits.
They are UL recognized per a statement from Schneider/Square D.
http://www.schneider-electric.us/sites/us/en/support/faq/faq_main.page?page=content&country=US&lang=en&id=FA115335&redirect=true
What is the UL file number for QOCGK2, QOCRBGK1 and QORBGK2 ?
The Square D Generator Circuit Breaker Interlock Kit, catalog number QOCGK2, QOCRBGK1 and QORBGK2 is a UL Recognized Component listed in UL File E6294, Vol. 7, Section 16, when installed in a listed QO Load Center (UL file E6294, Vol. 8).
The QOCGK2 and QORBGK2 do not carry their own UL number. They are listed as accessories only when used with the correct QO load center under UL file E6294 volume 7 section 16 page 1.
 
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