Hey Guys,
I've been wondering... how does the alternator regulator "assess" the battery SOC(state of charge) using the SENSE WIRE??!!,
Regulator can adjust the alternator current output(B+ wire) to the battery accordingly by controlling the amount of current it pass to the field coil.
Both SENSE wire and the B+ wire joins the battery, either as separate wires or joined each other somewhere between the alternator and the battery positive terminal.
Voltage of the alternator charge wire(B+) is always at minimum of 13.8V, and that's usually the voltage we measure at the battery as well(may be a fraction of a volt difference behind the alternator and at the battery terminal due to slight voltage through wire harness)
I guess, what I'm asking is whether the voltage that the regulator sense wire sense from the battery is somehow partially "compromised" by the alternator B+output to the battery itself!!! In other words, is it possible that the sense wire can't accurately assess the battery SOC, 'cos it can sense the voltage output of the alternator B+ as well?! Or does chicken or the egg question make any sense?
For example, if a battery is at 90% SOC, does the alternator regulator sense wire sense that accordingly and adjust the alternator output current? Or Is this the reason that the alternator can fail to charge a battery closer enough to battery's highest capacity due to "error" of regulator getting feedback from the alternator output voltage??!!
Or since the voltage and current are electrical measurements that are "directly proportional" to each other(assuming the battery resistance does not change with voltage), regulator can't increase the current flow to the battery without increasing the voltage(but keeping it regulated at maximum of 14.4V)??!!
Or if the battery SOC is pretty low, would me measure lot less than 13.8V(the minimum alternator output voltage or what is required to charge the battery at the battery terminals)??!!
Thanx in advance for any explanation(s)
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