Saw a guy hook up a ground wire before the power lead on a Garmin G5 install yesterday

He got lucky nothing popped but I had to stop him and explain why that order matters for the internal voltage regulator. Anyone else run into this with the new glass panel retrofits?

2 comments

2 Comments

lilymurphy9d ago

Hold up, ground before power is actually fine in a lot of these modern installs. The G5's internal regulator is built to handle a brief surge, and hooking up the ground first keeps the whole chassis at a steady reference point from the start. I've seen guys do it that way for years with no issues, and sometimes it even helps prevent weird voltage spikes when you're working with a battery connected. The real risk is if the power lead rubs against a hot terminal while you're fumbling with the ground, but that's more of a loose wire hazard than a sequence problem. You might be overthinking it based on some old school transistor logic that doesn't apply to these digital units. Unless you're running a plane with a sketchy electrical system, I'd say let the guy finish his install without the lecture.

lisa6719d ago

Honestly @lilymurphy, G5 installs are pretty forgiving for sure. I've seen a guy accidentally touch power to ground for a split second on one of those and it just shrugged it off. The real problem is when you're working in a tight panel and your spade terminal slips off the stud, that's where you get the sparks. I still prefer ground last on older planes with 60 year old wiring, but on a newer glass panel? You're right, it's not the end of the world if he does it the other way.