Siemens Sub Feed Lug Kit

Does this device require some form of tie down? I can’t find info online. A 125A exterior service panel feeds this subpanel.

If it is back feeding the panel, as you seem to describe, then, yes, the breaker needs to be secured to the remote distribution panel board.

That’s what I assumed. This was new construction. Work done by an electrician and approved by the city. I guess I’m curious if there are devices designed with some form of integrated tie down that isn’t visible?

Also, the device is not a circuit breaker. Maybe that bypasses the requirement?

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I dunno… :thinking:

Ahh, mea culpa, I missed that. :face_with_monocle:

Is the feeder for this panel attached to this lug kit accessory?

408.36(D) Back-Fed Devices. Plug-in-type overcurrent protection
devices or plug-in type main lug assemblies that are backfed
and used to terminate field-installed ungrounded supply
conductors shall be secured in place by an additional fastener
that requires other than a pull to release the device from the
mounting means on the panel.

Thanks, Rob,…good to know about plug-in type main lug assemblies that are backfed. :smile:

I found that as well but was a bit confused by the wording. Is the “lug kit accessory” a “plug-in type main lug assembly”?

The exterior service panel has a 125A that breaker is back-feeding a garage subpanel through the 125A lug kit accessory.

Where is the wiring connected to the bottom lugs coming from or going to?

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Whoops. Just realized my mistake. The panel is not backfed at all. That lug kit feeds a secondary subpanel in the home. I got the feeders mixed up. Ignore me. :face_with_head_bandage:

Thanks for clarifying. That confirms what I thought.

Thanks for the clarification. A back-fed breaker requires the hold down device because if it popped out it would be energized on both ends. If this device pops out it will just kill the feeder to the next panel.

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No. In the electrical trade that is known as a Tap. The conventional wisdom is that conductors are protected with a breaker or fuse at the source. However, in some instances it is more practical to provide protection at the opposite end.

From an engineering point of view, we know that to be acceptable because of Kirchhoff’s Current Law. From an overcurrent perspective, a fuse or breaker can be placed anywhere and still be completely effective.

There are, however, other considerations beyond overcurrent in the design and assembly of an electrical system. If a conductor is physically damaged, resulting in a fault, we want the overcurrent protection to be upstream. We limit the length of taps for this and related reasons.