Charging circuit question?

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dcarver

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Oh great gurus of all things Electron...

My 79 KZ1300 A1 has two independent charging systems.

Unfortunately, they are charging at full tilt, full RR output of 14.8 to 15.0 volts.

Found this really informative post from a Kz1300.com member..

Who basically said voltage drops on the 'brown' wire reduce volts introduced to the RR, thus 'tricking' the RR into thinking it needs full output, or at least more output than really needed, to charge the battery.

He mentions wiring straight from battery to RR via a switched relay.

My question is - why is the relay needed?

If wired direct to RR, bypassing all the other circuits on the 'brown' wire, I'm thinking it should be ok.. The voltage would be on the RR battery sense transistor, but the transistor should be off as it has power to switch?

Just wondering out loud..

Thanks in Advance!
 
Just guessing DC, but if you're wiring directly to battery with "brown" wire then you'd have a constant 12V on wire. Using a relay, would only have 12V on brown with bike running...

~G
 
Just guessing DC, but if you're wiring directly to battery with "brown" wire then you'd have a constant 12V on wire. Using a relay, would only have 12V on brown with bike running...

~G
That is correct :)

The battery sense wire (brown) at RR's (two of them) are now isolated from other brown wire circuits (key switch, lighting, etc) as I removed the brown wire pin from the connector.

So now I have to RR brown wires hanging in the breeze, isolated. Ran power to relay direct from battery, relay output (battery voltage direct!) to RR's brown wire battery sense voltage. Relay of course is switched.

I don't know that much about thyristors except that unlike a diode, they require a 'gate' voltage to energize, even given correct cathode/anode polarization.
 
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