Capacity of fuel pump relay driver?

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B1ack_Mi16
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Capacity of fuel pump relay driver?

Post by B1ack_Mi16 »

Just sprung to my mind, how many relays can the FP relay trigger output drive?

I'm using a factory loom as base for my build, and this has a multi-relay with two relay driver inputs.

In addition I've added a third relay myself, for the second fuel-pump which also is to be trigged by the MS3 fuelpump trigger output.

So in total 3 relays to be triggered. Might this be a problem?
DaveEFI
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Re: Capacity of fuel pump relay driver?

Post by DaveEFI »

In theory, about 1 amp. Most relays take about 0.2 amp. But you could feed your additional replays from the switched output of one of them. Just add a diode in series with the coil of each of the additional replays to prevent any reverse current flow.
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B1ack_Mi16
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Re: Capacity of fuel pump relay driver?

Post by B1ack_Mi16 »

Ok, I might just give it a go as it is first to see if it works then.

Not too keen on adding even more customization to the wiring loom, it's getting hard to keep under control :)
B1ack_Mi16
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Re: Capacity of fuel pump relay driver?

Post by B1ack_Mi16 »

Checked it today. Indeed 0.2 amps for the regular relay I used for the main fuel-pump.

The orginal double relay was 0.15 amps x 2. So in total 0.5A.

Guess I can just keep the wiring as it is then!
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