Fuse Question

[Welshman]

Ive got the following…..

100w Renogy Solar Panel
20amp MPPT Renogy Rover Charger
130ah Deep Cycle Battery

What size fuse between the battery and the MPPT please……..the leads came with a 20amp fuse installed

Thanks Guys

ps im going to connect it to a 12v 300watt inverter too, so what size fuse between the battery and inverter too.

 

[Ampster]

The fuse is to protect the wire so base the fuse size on the wire. You can always go with a smaller fuse if the expected load is less.

 

[Welshman]

The fuse is to protect the wire so base the fuse size on the wire. You can always go with a smaller fuse if the expected load is less.

So if the wire is 6awg…..how do i fuse it???

 

[Ampster]

So if the wire is 6awg…..how do i fuse it???

With the size fuse based on wire type and length based on table in Resource section. Here is a link:

Calculating Inverter DC Wire & Fuse Size

Note: Click on the Orange 'Download' button at the top of the page to get the paper. When designing a system, some of the most critical connections are the big wires to the inverter. The best advice is to do what the inverter manual says, but...

diysolarforum.com

 

[Welshman]

Ok….so if i have this right ….for the 300w inverter

(300/.90)/12) x 1.25 = 34.7a fuse……so round up to 40a and use 10awg cable

 

[Ampster]

It would depend on length, open air or conduit and Voltage drop that you can tolerate. My preference is always for bigger cable to reduce resistance.