See, I think the breakaway is backwards, particularly for a portable system.
To activate the failsafe breakaway, a contact closure is required. If you happen to forget to plug in the breakaway cable, then the brakes will work as normal, with no safety breakaway feature.
It should require a contact opening to trigger the failsafe: that way, you can't forget to connect this vital safety feature, because the brakes won't release until the breakaway is plugged in.
But that's just me...
2015 Fleetwood Bounder 35K
2021 Jeep Gladiator toad