Garmin GSB 15 Power Source?

[Bartman]

Hi all,

Anyone using the dual USB port Garmin GSB 15? Do you have it powered via the hot battery bus so you can charge phones and stuff when the plane is cold? Or do you switch it on with the master switch? Or is it switched on with the avionics master?

Curious to hear what ideas are out there.

Link for reference;

Garmin GSB 15 | USB Power & Charging for Aircraft

GSB 15 adds USB power and charging to your aircraft. The dual USB configuration gives simultaneous 3A high fast charging from each port.

www.garmin.com

Thanks!
Bart

 

[Big Ed]

My appareo USB charger is switched with the master. I think it would be a mistake to wire anything direct to battery. Master needs to shut off all current draws. Otherwise sooner or later you are going to forget and leave a device on there for a month and kill your battery.

I don't have an avionics master, but I wish I did. Is that spec for new aircraft? The original Bellanca spec is poorly designed, hence the SB for electrical update.

You'll need a dedicated fuse or breaker for the USB charger, btw.

 

[Bartman]

Yes, the factory uses an avionics master. The USB ports might as well switch on with the avionics master then to keep the port from being spiked every time the engine is started. Garmin specs a 7.5A breaker for it so I'm putting the power through the avionics master but each avionics component will have its own CB. Someone pointed out it would suck to have to switch off avionics power because one component is toasting itself, better to be able to pop the breaker and keep other stuff functioning.

in the thread where i'm obsessing over the panel layout I posted photos of a current spec ACA panel

8KCAB New Panel Idea

with the breakers on the panel which is the direction I'm going. Trying to get it all spec'd out and done in the next month or so. I'd kill for a diagram or schematic that has actual wire sizes indicated! Between AC 43.13 and other online sources there's some room for interpretation.

 

[Big Ed]

Yes, the factory uses an avionics master. The USB ports might as well switch on with the avionics master then to keep the port from being spiked every time the engine is started. Garmin specs a 7.5A breaker for it so I'm putting the power through the avionics master but each avionics component will have its own CB.

with the breakers on the panel which is the direction I'm going. Trying to get it all spec'd out and done in the next month or so. I'd kill for a diagram or schematic that has actual wire sizes indicated! Between AC 43.13 and other online sources there's some room for interpretation.

You might consider putting it on the main master instead of the avionics master. That way you do have the flexibility to charge up or power a phone on the ground in a pinch without powering up the rest of your avionics. Betcha that GSB-15 has spike protection baked in.

Are you going to put your engine monitor on your main or avionics master? I would think it would go on the main also, so you have engine gauge indications when you start. That's how I am going to install my round engine gauges when I convert to electric senders.

I would definitely put each component over 1A on it's own CB. I think you can combine smaller stuff, like 4 or 5 gauges or panel lights each drawing 0.1 or 0.2A, on a single 1A fuse or breaker. But I'm just spitballing.

You can always use bigger wire than required, so if any ambiguity, go big. No downside other than cost and weight, but both are probably trivial in an aircraft our size.

 

[Bartman]

JPI says to run the power for the engine monitor all of the way back to the Master solenoid and to just let it brown out during engine start if that's what it wants to do. At least that's how I read it in my first run through the manual last week.

I'll bet your right about spike protection, maybe the master switch would be a better idea. the breakers are pretty much figured out as are the switched breakers. the more I sit here working on it the more it's coming into focus. Between the factory drawing I have and the schematic in the old parts manual, I'm gradually figuring it all out. I like to figure out as much as I can before I call my IA friend for review and/or help. He looks at where I'm at and sets things straight before telling me to carry on. So much to do if the wings are going to have a chance of going on my mid/late summer.