Sense Monitor Breaker/Power from subpanel?

Will this particular configuration work? I technically have three panels on my house.

  • Main panel exterior of house
  • Small secondary panel exterior of house - a few inches to the left of main panel
  • Subpanel inside the garage feeding the bulk of the house

I did not have room for a new breaker in the main exterior panel, so I installed a new 15 amp 240V breaker in the exterior subpanel right next to the main. Red/Black to new breaker in subpanel and white to ground bar in that panel. The sensors are connected to the two incoming feeds in the main panel next to it. I just want to make sure there shouldn’t be any issues running the power/breaker for the Sense monitor in that subpanel next to the main. TIA!

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That should work as long as both sub-panels flow through the mains with the sensors.

Thanks, I assumed it wouldn’t be an issue. Can’t wait till it actually discovers some devices. Lurking around the community though it seems it could be hit or miss on the discovery piece.

Sense needs 240v to measure the voltage of both legs.
Yes, you can install the Sense unit in the sub panel (where your installing the breaker) and install the clamps in the main panel.
The one thing you cannot do is install the Sense unit itself in the main panel and power it from a breaker in the sub panel.


Are you not saying the exact same things twice and contradicting yourself? My sense monitor (physical orange box) sits in the bottom of main panel, with clamps on main power legs coming in. The 15 amp 240v breaker which is powering the sense unit is in a subpanel directly next to the main panel. The power cable runs through conduit from sense unit to the breaker to get power.

Support will usually suggest powering Sense by a breaker that’s in the same panel in which the main sensors are installed, however, the monitor should function as expected when the main sensors are installed in the main panel while Sense is powered by a breaker in the subpanel.

No, If you Sense unit (orange box) is in the main panel is must be powered from the main panel. If your Sense unit (orange box) is powered by a breaker in the sub panel it (the Sense unit box) can be located inside or outside that sub panel. It simply cannot be located inside a different panel.
The CT clamps by themselves (which are not considered power wires) can be ran back into the main panel (or wherever), just not the whole unit.

I’m not seeing why it would matter where it is getting power from since the CT clamps are on the main lines in the main panel. Either way I’m getting items discovered with the current setup and things seem to be working OK atm. Guess it will eventually be a moot point since I’m getting a whole new panel for a main shutoff and generator hookup in the next month or two. The new panel will hold around 30 circuits which will consolidate my two panels outside.

That’s what I assumed. I originally posed the question when I didn’t have anything being discovered yet, but things finally started popping in.

It’s not a matter of functionality.

Running the power wires (for the unit itself) from the breaker inside the sub panel to power a device located inside the main panel creates a quagmire of (legal) issues.

You can put the unit inside the main panel only if it is powered directly by a breaker on that main panel.
You can power the unit from a breaker in the main panel and place the unit outside the main panel.
You can put the unit in the sub panel only if it is powered by a breaker in that sub panel.
You can power the unit from a breaker in the sub panel and put the unit outside the sub panel.

The CT clamps (and wiring for the clamps) can be ran to and between either panel, it’s the power to the unit itself that’s the issue.

In case you are not already aware, Sense learns devices by the signature of the specific leg they are attached to. Quite often when installing a new panel circuits will be placed on different legs, the overall signature profile of a leg could change, or the CT’s themselves could be re-installed on different legs. If any of these things happen it is likely Sense will have to rediscover prior discovered devices.

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