Cable ties self adhesive bases to keep it all tidy.
Split charge relay fuse size.
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.
This minimises the unprotected length of cable the section from the terminal to the fuse.
It should be sufficient for most vehicle alternators.
Voltage sensed split charge relay 2.
If the cables runs total from alternator to relay relay to battery are long your 10mm cable may result in excessive voltage drop although safe enough it ll be ok up to around 7 or 8 ft but for 10ft i d use 15mm and for 15 ft 20mm.
When the engine is not running ignition is off the split charge relay will open and disconnect the batteries.
Sizing your split charge unit and connecting cables.
Winjun 4pin split charge relay switch 12v dc 200 amp heavy duty high current with connectors accessory.
Cable to connect everything together depending on the size of kit you purchased 3.
Watts divided by volts times 1 25.
Terminal heat shrink tube for car truck boat marine 4 6 out of 5 stars 21 12 99 12.
2 x fuse holders and fuses including spares 4.
Connect the other end of lead c to terminal 87 on the split charge relay.
The following formula will give you size fuse you need.
Connect lead c to fuse box 2 insert a 40amp strip link fuse and tighten both of the 8mm nuts.
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.
What size cable should i use for my split charge relay.
Connect lead b to terminal 30 on the split charge relay and the other end of the lead to fuse box 1.
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.
June 11 2019 at 3 26 pm.
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.