Dumb Electrical Question
Dumb Electrical Question The GTO/LS2 (and probably most other LSx engines) has the left and right injector/coil banks each fused on a separate 15A circuit.
If both of these circuits are wired through a common relay, does that relay need a capacity of 30A (or greater)?
Or would a 20A relay be sufficient?
If both of these circuits are wired through a common relay, does that relay need a capacity of 30A (or greater)?
Or would a 20A relay be sufficient?
You're taking two loads and combining into one. Now that one circuit has to handle twice the load, so the wiring and the relay have to handle the double load. So 30...
Andrew
Andrew
But it appears 20A ultra-micro relays are the largest available. If there are 30A ultra-micro relays, I'm not sure where to find them.
Last edited by TipsyMcStagger; May 28, 2019 at 01:37 PM.
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Let's assume we're talking about high impedance injectors.
A typical high impedance injectors draw about an amp. Even if all eight are on at the same time, current draw would be about 8A. A 20 amp relay should be fine.
The fuse is designed to protect the wiring against a short circuit, so the max size of the fuse is designed based on the wire gauge rather than the load. You're doubling the number of injectors, but you're not increasing the size of the wiring feeding any injector. I don't think a 30A fuse is a good idea. A single 20 amp fuse should be fine.
A typical high impedance injectors draw about an amp. Even if all eight are on at the same time, current draw would be about 8A. A 20 amp relay should be fine.
The fuse is designed to protect the wiring against a short circuit, so the max size of the fuse is designed based on the wire gauge rather than the load. You're doubling the number of injectors, but you're not increasing the size of the wiring feeding any injector. I don't think a 30A fuse is a good idea. A single 20 amp fuse should be fine.
Let's assume we're talking about high impedance injectors.
A typical high impedance injectors draw about an amp. Even if all eight are on at the same time, current draw would be about 8A. A 20 amp relay should be fine.
The fuse is designed to protect the wiring against a short circuit, so the max size of the fuse is designed based on the wire gauge rather than the load. You're doubling the number of injectors, but you're not increasing the size of the wiring feeding any injector. I don't think a 30A fuse is a good idea. A single 20 amp fuse should be fine.
A typical high impedance injectors draw about an amp. Even if all eight are on at the same time, current draw would be about 8A. A 20 amp relay should be fine.
The fuse is designed to protect the wiring against a short circuit, so the max size of the fuse is designed based on the wire gauge rather than the load. You're doubling the number of injectors, but you're not increasing the size of the wiring feeding any injector. I don't think a 30A fuse is a good idea. A single 20 amp fuse should be fine.
You're suggesting combining both left and right injector/coil banks into a single 20A fused circuit?
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I wasn't planning a single 30A fuse. I was was planning two separate 15A fused circuits (one for the left injector/coil bank, one for the right injector coil bank), both run through a common relay.
You're suggesting combining both left and right injector/coil banks into a single 20A fused circuit?
You're suggesting combining both left and right injector/coil banks into a single 20A fused circuit?
I don't have any data on coil current requirements, but I would guess they have a larger current draw than high impedance injectors.
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Sorry, I must have been tired when I read what your plans are. I didn't notice that you're also running the coil banks on the same circuit as the injectors, so my previous comment is not applicable.
I don't have any data on coil current requirements, but I would guess they have a larger current draw than high impedance injectors.
I don't have any data on coil current requirements, but I would guess they have a larger current draw than high impedance injectors.
There doesn't seem to be a 30A ultra-micro relay available to fit in the Bussmann block, so I'll use a different fuse block and run both 15A circuits through a 30A relay.
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You can put all injectors and all coils on one micro relay in the bussman box. They are rated @35 amp. Protect the circuit with a 15 amp fuse. We have done thousands of these over the years with this setup. On the ls system the total current draw on coils and injectors at full throttle is approx 12 amps. Yes I know each injector pulls approx 1 amp however they are not all on at the same time. Steve
Last edited by EFIHARNESS; May 29, 2019 at 07:28 PM.
You can put all injectors and all coils on one micro relay in the bussman box. They are rated @35 amp. Protect the circuit with a 15 amp fuse. We have done thousands of these over the years with this setup. On the ls system the total current draw on coils and injectors at full throttle is approx 12 amps. Yes I know each injector pulls approx 1 amp however they are not all on at the same time. Steve
If so, that surely simplifies things!