solar fuses

[Muddydogs]

What fuses are you guys using to connect you solar panels to controller and controller to battery's?

[pianotuna]

Hi Twomed,

Yes, but how many watts?

Twomed wrote:
40a on the roof, disconnect box with 40a in 30a out after Tristar60

Fuses are cheap... fire is expensive, pretty simple. ??

[TechWriter]

Muddydogs wrote:
What fuses are you guys using to connect you solar panels to controller and controller to battery's?

In my three 245W panel setup, I use MidNite Solar MNEPV breakers (not fuses):

• Panel-To-Controller: MNEPV 15 (15A, 150VDC)
  
  
• Controller-To-Batteries: MNEPV 63 (63A, 150VDC)
  
  

[2oldman]

MEXICOWANDERER wrote:
What happens to an MPPT controller if the controller to panels conductors are shorted?

Shorted as in, "connected together?"

Fuses are not required for series PV installations, as mine is. Go ahead, tear me apart.

[pianotuna]

Hi Mex,

I'm at 256 watts so I did not feel I needed a fuse between the panels and the controller. I've not tried shorting it out. If I were at a higher wattage I would consider it prudent to fuse.

Shorting between controller and batteries without a fuse turns the wire into the fuse.

MEXICOWANDERER wrote:
Just a question or two if I may...

What happens to an MPPT controller if the controller to panels conductors are shorted?

What happens to the wires connecting the controller to the battery bank if it should develop a dead short?

[2oldman]

Muddydogs wrote:
only fuses I have used are the ones that take auto spade fuses. Just not sure what to use for this application.

I doubt it makes any difference what kind, as long as the amp rating is appropriate.

[MEXICOWANDERER]

Just a question or two if I may...

What happens to an MPPT controller if the controller to panels conductors are shorted?

What happens to the wires connecting the controller to the battery bank if it should develop a dead short?

[Muddydogs]

From all I read the info say to fuse the hot line from the controller to battery as well as solar positive line.

I am looking for types of fuses as well, only fuses I have used are the ones that take auto spade fuses. Just not sure what to use for this application.

[Twomed]

40a on the roof, disconnect box with 40a in 30a out after Tristar60

Fuses are cheap... fire is expensive, pretty simple. ??

[pianotuna]

Hi,

none between panels and controller

I do have switches to disconnect the batteries. They incorporate a 35 amp fuse.

[2oldman]

none