It seems Emporia’s Gen 2 installation introduces an electrical shock hazard!

[ihabosman]

When no slots are available to add new circuit breakers for Emporia’s Gen 2 use, the installation manual – Page 18 – suggests using two existing but different pole breakers. However, shutting down any of the two Emporia’s shared circuit breakers does not seem to de-energize an individual breaker circuit. It seems Emporia reenergizes the disconnected circuit from the still connected (i.e., 120 VAC) opposite pole breaker!

Such a situation could create a dangerous electrical shock if someone assumes erroneously they just need to disconnect a single breaker, not both breakers, to perform any electrical work on that disconnected circuit!

The solution requires a tie handle for both breakers to shutdown both split-phase breakers simultaneously (like the Code requirement for a multi-branch wire circuit, which also uses two poles and requires a tie handle).

This suggestion is critical safety advice.

[megachase]

I think the solution is a quad 15A 2-pole tandem breaker with a common trip in the middle. That’s what I plan to do because I don’t like the idea of hot wire nuts with no strain relief down the side of my panel.

[wbarber69]

Not sure what country you are in, but in the US you don’t simply such a bar across two breakers, they don’t work like that.  You need a common trip breaker.  Basically, you either need to add in a single 2 pole breaker to power your vue, or use something like your stove or hvac breaker to provide the power. In a 3 phase situation you’d need to have a 3 pole breaker to do the job.  Never assume that power is off when it’s obviously not because you’ve tied your power meter to different phases.  Once again, simply bonding two breaker handles together is not going to work. You can manually flip the two breakers off in this manner, but when a breaker trips is does not make a full draw on the switch.  It only clicks back about half the amount of draw you’d need to fully deenergize a breaker.  This will have the second breaker still energized and it’s handle will simply be in the almost off position.  Only use breakers with common trip.  These breakers not only have the handles bonded, but the entire housing is bonded as well, and they have internal devices that ensure that both legs get tripped simultaneously.  They are not simply 2 breakers stuck together, there’s more to it than that.

[megachase]

Hey WB, I assume your post is in response to ihab’s OP but it pinged me anyway.  It looks to me like you are suggesting double lugging the little 18ga wire into something like a 50A range breaker along side probably 6ga wire or similar, at the higher torque I assume. That led me to do a quick check and I noticed that the one exemption where the NEC allows double lugging on is whole home surge protectors.  That got me thinking about if there could be an advantage to piggybacking the Emporia with an SPD.  At least if you are local monitoring you can assume that if the Emporia goes offline but the lights are still on, you may have had a surge. Even by remote if your cameras are still on, or say a smart plug in a non emergency power fed circuit is still on.  Don’t know if this topic is covered elsewhere, just thinking out loud.

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