[alpinelakespilot2000]

I assumed as the D120 came up that the power was fine. I had put a 2A fuse by mistake instead of the recommended 3A fuse.
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My D180 calls for a 2A fuse, but the fuse keeps blowing if I try to run it off the main buss (and only if my DB37 is connected). I upgraded firmware a year or so ago, but is there, by chance any requirement to use 3A now rather than 2A?

thanks.

 

[Dynon]

It matters if you have a internal battery or not. You can get away with 2A with no battery, but when we charge the battery it puts us above that.

Also, when you crank the engine to start, and your voltage drops, the current draw goes up, which may also cause a 2A fuse to blow, depending on a whole variety of factors.

The current manual does recommend a 3A fuse on page 2-2. I can't remember if we ever changed this.

Also, as is always true, the fuse is there for the wire, not the instrument, so as long as your wire can handle your fuse, you'll be OK.

 

[alpinelakespilot2000]

Great. Thanks. I do have the internal battery so that could be the issue. I found a newer D180 installation manual online and, indeed, it shows to use a 3A rather than a 2A that my older manual indicated. I'll give the 3A a try and see if that does the trick.

This might be a good time to suggest that builders who purchased/installed their D180s a couple years ago to look over the newer installation manuals.

 

[Dynon]

I glanced back at all 7 revisions of the D180 install guide, and they all recommend a 3 amp fuse. I think the confusion is that they also mention a 1.5 amp "nominal" current draw, which is true, but not when the battery charges.

I see from our forum that you are only having the issue with the D37 "misc" connector hooked up, and the main culprit on this connector is going to be the 5V or 12V output lines (for sensors and the fuel flow senders). So if the 3A doesn't fix it, start looking there.

 

[alpinelakespilot2000]

I glanced back at all 7 revisions of the D180 install guide, and they all recommend a 3 amp fuse. I think the confusion is that they also mention a 1.5 amp "nominal" current draw, which is true, but not when the battery charges.

Thanks. I'll check when I get home. I do know for sure that my wiring harness schematic (from Pacific Coast Avionics) specifies a 2A fuse, but was pretty sure I saw it elsewhere as well.

Will check the excitation wires as well. I'm assuming I'd be looking for nicks somewhere where one of those wires would be shorting?

Thanks again.