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ANL fuse and ammeter shunt mounting

iamtheari

Well Known Member
I'm using a Vertical Power VP-X instead of circuit breakers, so I don't really 'need' an ammeter. But it is still probably a good idea to have one as a second data point, especially if there ends up being debugging to do.

I also don't know much about ANL fuses and whether they are necessary or just a good idea.

Who has pictures or stories about mounting these items on their RV-14 firewalls? I figure I should get that figured out before I mount the engine and make drill access harder.
 
I also don't know much about ANL fuses and whether they are necessary or just a good idea.

Who has pictures or stories about mounting these items on their RV-14 firewalls? I figure I should get that figured out before I mount the engine and make drill access harder.

I also used a VPX, and my understanding is you do not need to install a shunt, but I believe the ANL fuses are still required. I installed one for each alternator. This photo shows where I mounted them. I installed them after the engine was on. Stein told me not to worry about installing the variety with a cover or mounting them inside - on the firewall is fine. Sorry I don?t have a closer view.

ejalh0.jpg
 
See photos in my post here. I did one ANL fuse for each of my two (primary and standby) alternators. Both ANL fuses to one side of shunt, along with battery cable. Other side of shunt goes to the thru-firewall cable to avionics etc. 3rd photo on the page shows it best.

https://turnerb14a.blogspot.com/2018/12/more-cowl-baffles-wiring-control-cables.html

Also - look at last photo on this page. Vic Syracuse helped me draw out the layout on firewall before alternator and batter wiring and output from the shunt to main buss was ever done:

https://turnerb14a.blogspot.com/2018/11/big-day-today-progress-continues-on-all.html
 
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Resurrecting my thread. The Garmin ammeter shunt is rated for 100 amps. Above that, will it blow like a fuse or will it melt down like Chernobyl?
 
Resurrecting my thread. The Garmin ammeter shunt is rated for 100 amps. Above that, will it blow like a fuse or will it melt down like Chernobyl?

Assuming it would behave like a fuse, would you be comfortable with 100 amps of current flowing through there? ANL fuse seems like a good safety measure to me as well as protection for components in the system.
 
Assuming it would behave like a fuse, would you be comfortable with 100 amps of current flowing through there? ANL fuse seems like a good safety measure to me as well as protection for components in the system.
The typical wiring seems to be that the ANL fuse sits between the alternator and the main bus, and the ammeter is either in series with the ANL fuse or between the battery and the main bus. I would probably put the ammeter in series with the ANL fuse and have a measurement of what the alternator is putting out from the ammeter. The VP-X will measure the current of what things are using, so the difference should be flow to and from the battery (less whatever current is flowing to hold the master relay open). But the circuit between the battery and the VP-X will not have a fuse or fuse-like device, so I was thinking about whether it makes sense to put the ammeter shunt there and at least have some protection against a battery-to-ground open circuit.
 
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