Fuses and CB's

[Brian Cornes]

Hello, I'm building a 7 with a slider canopy so wont have access to the instrument sub panel, I want to fit fuses and some CB's. If anyone else has done this, can you advise where to mount the fuse boards please?
My proposed panel is below:

Many thanks
Brian
RV7
G-RVBL

 

[JonJay]

Remove your redundant analog fuel gages and there’s plenty of room to put stuff there if you must.
Or, use ATC fuse blocks behind the panel.

 

[Scott Hersha]

Here’s how I did mine - RV6 slider. I can easily, although blindly, reach my fuse panel if needed in flight. I have a location “map” of fuse layout with my expanded checklist. When I was still flying for pay my airline had a circuit breaker policy. We seldom ever reset a CB in flight. The small fuse block on the left is my aux bus, the big one in the middle is my main bus, and the small one on the right is my avionics bus.

 

[Desert Rat]

I did this. If you ditch the glove box there's enough empty panel space on the right of a 10" MFD to get 29 breakers in there plus an ELT remote switch if you pack everything tight. But on a gadget heavy IFR plane you can still run out of room for breakers.

On mine, stuff that isn't mission critical got put on a fuse block on the aft face of the firewall forward and above the copilot rudders.

I defined mission critical as stuff like landing lights, nav lights/strobes, fuel sending unit sensors, underwing camera, etc. basically stuff that there's no concern about load shedding because theres already a switch on the panel, and also that I wouldn't try to reset in flight if the breaker popped.

 

[JonJay]

Brian - if you use the search you can find many discussions on fuses vs breakers vs electronic load centers etc… , and much on locating these as well.
No wrong answer just different thoughts. Eventually, you just have to decide what’s right for you and go with it.
I’ve done all three….

 

[RV7 To Go]

I made a hinged door under the panel for my fuse blocks, held up by 2 quarter turn wing style fasteners. Could be accessed in flight, although personally I wouldn't troubleshoot in the air.

 

[bardample]

Can I suggest : No analogue fuel gauges. No glove/map box. I installed one and it limits future real estate, and access . You can put your fuse plates or anything there. Map box extends through subpanel. I suggest side pockets may be more useful.

I have fuse blocks over to R side , and resettable fuses for my pMags.

 

[D-Dubya]

Can I suggest : No analogue fuel gauges. No glove/map box. I installed one and it limits future real estate, and access . You can put your fuse plates or anything there. Map box extends through subpanel. I suggest side pockets may be more useful.

+1 for this. I have side pockets sewn into my side panels about where my knee is. It works.

You could still put fuse blocks on the sub panel, but they're a little tough to access. No worse than some cars. Well, maybe a little worse since you can't lay on the floor with your legs hanging out the door like on a car.

 

[DanH]

Swings down from under the panel:

When I was still flying for pay my airline had a circuit breaker policy. We seldom ever reset a CB in flight.

This. Inflight access to a fuse is regulatory, not sensible.

 

[Walt]

Swings down from under the panel:


This. Inflight access to a fuse is regulatory, not sensible.

That's not really what 91.205 means:

*"One spare set of fuses, or three spare fuses of each kind required, that are accessible to the pilot in flight."

If they're not accessible, then no spares are necessary.

 

[mfleming]

So if a fuse pops in IMC or at night, who in their right mind is going to try and instal a spare fuse.
Also, if the fused device is unnecessary for flight or there is a back-up device on a seperate circuit, no spare fuses required. Also, there is no requirement for the pilot to replace the fuse, just carry them. IMHO this requirement is a leftover from the old days and not relevant now.

Just an aside, I'm not re-setting a breaker or installing a fuse inflight no matter what.... I'm troubleshooting on the ground.

 

[Walt]

So if a fuse pops in IMC or at night, who in their right mind is going to try and instal a spare fuse.
Also, if the fused device is unnecessary for flight or there is a back-up device on a seperate circuit, no spare fuses required. Also, there is no requirement for the pilot tho replace the fuse, just carry them. IMHO this requirement is a leftover from the old days and not relevant now.

Just an aside, I'm not re-setting a breaker or installing a fuse inflight not matter what.... I'm troubleshooting on the ground.

Back in ‘the day’ when aircraft still had glass twist to lock fuses, I could understand it, but definitely super outdated.

 

[Brian Cornes]

I made a hinged door under the panel for my fuse blocks, held up by 2 quarter turn wing style fasteners. Could be accessed in flight, although personally I wouldn't troubleshoot in the air.

View attachment 117763

I like this idea very much, what was it like to hinge down when fully wired? thanks for sharing much appreciated

 

[DanH]

Bring the wire bundles in from the sides so the bundle only sees a ~100 degree twist in torsion over some length.

 

[RV7 To Go]

I like this idea very much, what was it like to hinge down when fully wired? thanks for sharing much appreciated

Yep....what Dan said. No problem lowering the door.