The following formula will give you size fuse you need.
Split charge relay fuse size.
Connect lead c to fuse box 2 insert a 40amp strip link fuse and tighten both of the 8mm nuts.
Terminal heat shrink tube for car truck boat marine 4 6 out of 5 stars 21 12 99 12.
8mm to 10mm terminals spare terminals heat shrink pack for modifications if required.
When the engine is not running ignition is off the split charge relay will open and disconnect the batteries.
Watts divided by volts times 1 25.
What size cable should i use for my split charge relay.
Cable to connect everything together depending on the size of kit you purchased 3.
This minimises the unprotected length of cable the section from the terminal to the fuse.
June 11 2019 at 3 26 pm.
It should be sufficient for most vehicle alternators.
Typically split charge relay is controlled by the ignition wire so that when the engine is running ignition is on the split charge relay will close and connect both main battery and auxiliary battery.
2 x fuse holders and fuses including spares 4.
So if you re blowing 15a fuses with a 150w led setup then i think it would be better to try a 20a fuse with wire and relay sizing to match.
Each battery that connects into the split charge device should have an appropriately rated fuse installed in line with the cable as close as possible to its ve terminal.
Cable ties self adhesive bases to keep it all tidy.
1 x 500mm 110amp red relay to fuse box lead 6mm to 6mm terminals 1 x 250mm 110amp red fuse box to leisure battery lead 6mm to 8mm terminals 1 x 1000mm 110amp black earth cable.
Winjun 4pin split charge relay switch 12v dc 200 amp heavy duty high current with connectors accessory.
Connect the other end of lead c to terminal 87 on the split charge relay.
Sizing your split charge unit and connecting cables.
When installing the cable in your split charge relay system use a cable of at least 16mm2 cross section 110a and upwards.
If you are concerned about the size of your relay you must also consider the rating of your wiring and fuse fuse holder there is little point fitting a wopping great relay if the rest of it is not able to handle it do you know the max rated output of your alternator some of the modern ones can run at between 150amp to 200amp the average is between 55amp to around 80amp though.