How many amps?

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Ian Anderson
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Re: How many amps?

Post by Ian Anderson »

DaveEFI wrote:
Sun May 03, 2020 12:36 pm
I can actually remember the days when 30 amps would cover the entire electrical load. :D Add a spotlight - as you did - and you were in trouble.
Sounds like my old Morris Minor out in Africa, lights were dismal, so I added two spot lights, the generator could not keep up, so with spots on I had to turn main lights off / sidelights on only, it was an art form turning off the spots, and turning on the headlights when someone came over a rise / around corner towards me!


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Re: How many amps?

Post by DaveEFI »

Yup - had an MG ZA Magnette. Fog and spot factory fitted. Could both be run with headlights on. But factory didn't fit a large enough dynamo to cope with that load. We're a bit spoiled these days. :D
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Re: How many amps?

Post by stevieturbo »

DaveEFI wrote:
Sun May 03, 2020 9:09 am

If none exists, perhaps a clamp meter would give an idea. But difficult to use with the car in use.
Easy enough ( maybe a little messy though depending on access )...just route the main alternator cable somewhere accessible so you can access it and also view the meter.

Or easier still

Clamp meter for a scope which you can datalog, or a lot of cars do now have clamp current transducers for monitoring current. Get one of those and datalog it.
Cheap one here from our wonderful Chinese friends :twisted: , powered by a PP9 battery and just outputs an analogue voltage, so easy to datalog on your ecu ... SwOJJauKuP

Holley are reselling some, but not sure what actual vehicle they are from. But if you search ebay, you can find all shapes and sizes from cars here too, so it is a common feature on modern stuff, and I presume most just output a 0-5v voltage, although if doing DIY you'd need a means of calibration. ... ts/554-171
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Re: How many amps?

Post by voltariders »

Of course better stick with a quality battery for a car, because its a critical component.
Personally I've searched a lot about this topic and found some interesting articles like this.

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