Battery Cutoff Switch
02-16-2010, 05:49 PM
#16
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My Yamaha R1 engine (with alternator) in the formula car is wired how I described and shuts down all the time every time with the emergency cutoff. ???? Oh well... whatever works for each individual and the organization he runs with.
I think I just figured out why that is the case. On the Porsche, the alternator/regulator ground terminal runs to chassis ground, thereby completing the circuit. On my car, I've run the positive and negative terminals from the regulator directly to the battery, bypassing the chassis ground. When I throw the cutoff switch on my car, all current to the FI and ignition (and ECU) is off, so the engine stops. As it stops, the access current is flowing directly to the battery (which is the exact same PC680 in your picture).
I think I just figured out why that is the case. On the Porsche, the alternator/regulator ground terminal runs to chassis ground, thereby completing the circuit. On my car, I've run the positive and negative terminals from the regulator directly to the battery, bypassing the chassis ground. When I throw the cutoff switch on my car, all current to the FI and ignition (and ECU) is off, so the engine stops. As it stops, the access current is flowing directly to the battery (which is the exact same PC680 in your picture).
02-16-2010, 11:57 PM
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Thanks to both of you for all of the help!!
Garrett376, I printed out your post on the 6-pole switch as well as the picture of your trunk and the battery cable set-up. Hopefully I will get the switch in the mail this weekend, and be able to sort the mess a little bit.
Garrett376, I printed out your post on the 6-pole switch as well as the picture of your trunk and the battery cable set-up. Hopefully I will get the switch in the mail this weekend, and be able to sort the mess a little bit.
12-04-2011, 12:18 PM
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I like this idea for my drive....just a remote switch any other considerations re the electrical system or the ecu having to remap ?
I went to their web site which switch would you recommend ?
I went to their web site which switch would you recommend ?
After thinking about this a little more, I would use an electrical relay as the battery cutoff switch. You can get an aircraft type from Aircraft Spruce for about $35.00. Then you can put a simple two pole toggle switch on the dash to control the relay. No cable... works to turn off AND on. But you could not flip the toggle switch off while the car is running unless you ran the two wires from the alternator terminals as I described.
