ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat Box
Recent Posts
Unusual Well Pump Switch Failure
by sabrown - 10/28/20 04:31 PM
Look at this mess...
by InspectorE - 10/27/20 09:09 PM
New tool
by gfretwell - 10/24/20 11:09 AM
Where is Everyone?
by Bill Addiss - 10/17/20 07:04 PM
New in the Gallery:
Facebook follies, bad wiring
FPE in Germany pt.2
Who's Online Now
1 registered members (Scott35), 18 guests, and 12 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Transfere ''Clip'' #80076 02/22/02 06:36 AM
Joined: Oct 2000
Posts: 5,389
S
sparky Offline OP
Member
Sq D makes a 'Handle Interlock' , or commonly refered 'Transfere Clip', part # QO2DT1 ( sorry, i could not find a link....)

This is a simple little piece of metal that acts in a see-saw manner when mounted between two 2-P breakers.

Both the latter can not be on @ the same time due to said 'Clip'.

As one of the two breakers may be 'backfed', there is a 'breaker hold down bracket' which is required. I noticed this mentioned inside a SQ D cover's sticker.

Now this entire arrangement might top $15 in parts & seems to be kosher... [Linked Image]
The simplicity and $$$ blows me away...

But I don't see a whole lot of these, as compared to the average T-switch, or Gen-Tran, nor have i installed one....

So i'd like to ask here, are there applicable codes,listings, concerns, etc that i've missed?

Is this a setup simply more common than i've seen?

Unfuzz me please... [Linked Image]

2017 / 2014 NEC & Related Books and Study Guides
Re: Transfere ''Clip'' #80077 02/22/02 09:54 AM
Joined: Jul 2001
Posts: 599
J
JBD Offline
Member
The Mechanical Interlock Attachment you describe (SQD #QO2DTI) is intended as a means of preventing two loads from being connected at the same time not as a transfer switch.

However if you use the interlock with (2) breaker retaining clips then it is UL Listed as a manual transfer switch in "dual power supply applications". But only when installed in a SQD #QO816L100 load center.

You can also buy it in kit form (SQD PK4DTIM4xx) for use in newer series main lug only loadcenters.

All of this information is from Square D's Digest #172 page 1-9.

Re: Transfere ''Clip'' #80078 02/22/02 12:37 PM
Joined: Dec 2001
Posts: 270
E
Elzappr Offline
Member
I think you would have to concern yourself about making sure one breaker disconnects its load before the next one connects.."break before make". I don't think the device you talked about does that.

Re: Transfere ''Clip'' #80079 02/22/02 03:31 PM
Joined: Oct 2000
Posts: 5,389
S
sparky Offline OP
Member
Elzappr;
actually it does, but it's a God awful little piece of tin to depend on....

JBD;
thanks, i see the 1-9 accessory page. But I am [Linked Image] because it would seem to be a T-switch for a 8-16 circuit panel only.

The NEC falls short of a definition of a T-switch, and i really can't stand on 700 or 701, as the application is residential, not an 'emergency' or 'legally required' criterion.
Should i seek a 'listing' answer here?

Re: Transfere ''Clip'' #80080 02/25/02 10:07 AM
Joined: Jul 2001
Posts: 599
J
JBD Offline
Member
Sparky, look further doewn the page at Manual Transfer Equipment Kit.

This little piece of tin is the same device SQD uses in their UL Listed Generator panel shown on page 1-8.

Re: Transfere ''Clip'' #80081 02/25/02 07:22 PM
Joined: Oct 2000
Posts: 5,389
S
sparky Offline OP
Member
JBD,
my cat is a 97', but i'l take your word for it, thanks.


Featured:

2020 National Electrical Code
2020 National Electrical
Code (NEC)

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
CDS
CDS
Nicholson Ga
Posts: 34
Joined: June 2006
Show All Member Profiles 
Top Posters(30 Days)
Popular Topics(Views)
271,034 Are you busy
205,039 Re: Forum
193,154 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.3