I guess I should have used a visual at the outset !!!
Here is a different way of explaining that hopefully is a bit clearer:
I think we are all agreed on the following :
1) Changing Star (Wye) to Delta does NOT increase alternator output power
2) Changing Star to Delta simultaneously INCREASES ac Current output by SQR(3) and DECREASES ac Voltage output by same SQR(3)
What I previously didn't make clear is this :
A) I have an 12v device (air con) that benefits from higher current output and can handle the lower voltage (in fact it is more efficient at the lower voltage )
B) my question was specifically related to the cut in speed as nicely shown by this sample graph :
Cut in speed is tricky to calculate without having the original alternator graphs so was wondering if anyone had done it and could let me know what they found
The typical solution is to change the gearing on the high output alternator and spin it faster, not an easy option on the ST1100
(the reason I want high current at low speeds is because its when I'm sitting in traffic that I want the air con to be effective, it doesn't have to be so effective at crusing speed)
(and the reason why I am experimenting with air con is a long story involving several personal experiences that involve baking in 50C (122F) heat )
Hopefully that clears up a lot of the discussion points and lesson learned on my part, next time its something technical use a visual !!
Here is a different way of explaining that hopefully is a bit clearer:
I think we are all agreed on the following :
1) Changing Star (Wye) to Delta does NOT increase alternator output power
2) Changing Star to Delta simultaneously INCREASES ac Current output by SQR(3) and DECREASES ac Voltage output by same SQR(3)
What I previously didn't make clear is this :
A) I have an 12v device (air con) that benefits from higher current output and can handle the lower voltage (in fact it is more efficient at the lower voltage )
B) my question was specifically related to the cut in speed as nicely shown by this sample graph :
Cut in speed is tricky to calculate without having the original alternator graphs so was wondering if anyone had done it and could let me know what they found
The typical solution is to change the gearing on the high output alternator and spin it faster, not an easy option on the ST1100
(the reason I want high current at low speeds is because its when I'm sitting in traffic that I want the air con to be effective, it doesn't have to be so effective at crusing speed)
(and the reason why I am experimenting with air con is a long story involving several personal experiences that involve baking in 50C (122F) heat )
Hopefully that clears up a lot of the discussion points and lesson learned on my part, next time its something technical use a visual !!
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