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i am planning on hardwiring my fuel pump to the battery and I bought some wire from supercheap that is 15 amp wire, so I’ll also have a 15 amp fuse between the battery and the relay, and I’ll use the same wire for all the other terminals on the relay. just wanting to know if there will be enough current for the fuel pump, or do I need thicker wire. Thanks


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What was the factory fuse rated for?

Just use one of the same rating (and.obviously wire to suit)

Are you re-wiring the standard bulkhead connector at the tank, or putting in a new/additional one?

Current draw will depend on a few factors. What pump are you using? Fuel Pressure? Injector Size? Voltage at the pump? Wire run length?

1m of 15amp wire (AWG 14 - 2.08mm²) will see a 0.25v drop. To achieve 0.05v loss you would need to use AWG 7 (10.5mm²)

Example

Magpie wrote:Current draw will depend on a few factors. What pump are you using? Fuel Pressure? Injector Size? Voltage at the pump? Wire run length?

1m of 15amp wire (AWG 14 - 2.08mm²) will see a 0.25v drop. To achieve 0.05v loss you would need to use AWG 7 (10.5mm²)

Example

So based of that chart if I’m running at 60psi 70 gallons an hour I would only need a 14amp wire. Is that correct? as far as length goes yeah power to battery is around a metre


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At 12v and 60 psi you can flow a max of 51 g/hr (190 l/hr) and the pump will draw about 9 amps.

Ok thanks, so the 15 amp wire should be more then enough


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