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Electrical power: how much is available?


DGuy

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Greetings:

Just wired my 900GT so I can use my electric vest which takes about 5Amps... and it got me to wondering how much power is available.  Has anyone here looked into this, is it documented somewhere?

Just how much farkle can I put on this bike?

TIA,

Guy

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If you are wiring directly to the battery, via a fused power distributor, then you’ll be fine hooking multiple items up. Just keep them to separate “circuits” 

Like this fuze block


Fuzeblocks FZ-1 power distribution block: Amazon.co.uk: Car & Motorbike

 

Red 2015 Tracer, UK spec (well, it was until I started messing with it...)

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Service manual says stator outputs 14.0VAC, 29.6 A @ 5k rpm.
The rectifier outputs 14.3-14.7 VDC with a capacity of 50A, but that's it's capacity rating, not actual output.
I would guess then based on the stator, you have a total of 38amps at 12 VDC to play around with minus the OEM draw whatever that is.

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1 hour ago, DGuy said:

Greetings:

Just wired my 900GT so I can use my electric vest which takes about 5Amps... and it got me to wondering how much power is available.  Has anyone here looked into this, is it documented somewhere?

Just how much farkle can I put on this bike?

TIA,

Guy

In addition to what @BBB mentioned, there are also "switched" auxiliary power leads available behind the screen on a 2amp circuit. 

I have my battery tender lead connected direct to the battery, which I also use to power my heated vest and I have my GPS and daytime running lights wired to the switched power leads behind the screen. 

What devices are you wanting to connect?

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***2015 Candy Red FJ-09***

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One important thing to keep in mind is the current draw for a USB powered device (at 5 volts) doesn’t translate to the same current draw on the 12 volt side of the bike’s charging system.    That’s why those 2 amp fuses on the accessory circuits (24 watts max power delivery) can support about 4.8 amps of USB connected devices...  transformer loss not withstanding.   

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Thanks everyone for the info...Not interested in connecting anything else...I'm just curious as to what kind of power overhead exists on this bike, now I know.  More power than I foresee ever needing.

BTW I am an electronics professional...

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10 hours ago, DGuy said:

BTW I am an electronics professional...

I’m looking forward to your posts on people’s electrickery woes in the future 👍🏻

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Red 2015 Tracer, UK spec (well, it was until I started messing with it...)

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4 hours ago, BBB said:

I’m looking forward to your posts on people’s electrickery woes in the future 👍🏻

Well I'll do my best but understand, there's a big difference between ELECTRICAL systems of a motor vehicle and ELECTRONICS.  ;-))

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On 2/11/2020 at 11:18 AM, kilo3 said:

Service manual says stator outputs 14.0VAC, 29.6 A @ 5k rpm.
The rectifier outputs 14.3-14.7 VDC with a capacity of 50A, but that's it's capacity rating, not actual output.
I would guess then based on the stator, you have a total of 38amps at 12 VDC to play around with minus the OEM draw whatever that is.

Not to be rude, but I think you misread the manual (or the manual has a typo). I seriously doubt that the stator output is 14Vac; bike alternators are traditionally in the 30-60Vac range. Not to mention, the RegRec is NOT going to output a HIGHER voltage than the stator! 😉

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11 minutes ago, TTR Ignition said:

Not to be rude, but I think you misread the manual (or the manual has a typo). I seriously doubt that the stator output is 14Vac; bike alternators are traditionally in the 30-60Vac range. Not to mention, the RegRec is NOT going to output a HIGHER voltage than the stator! 😉

From horse's mouth.
49526270776_26777209ff_o.png

A diode rectifier can't output more voltage, but a transistor certainly can, and I assume they are just using an off the shelf shindengen mosfet rec/reg.

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3 minutes ago, kilo3 said:

A diode rectifier can't output more voltage, but a transistor certainly can

Only if it's connected to a higher-voltage source. A transistor (or mosfet) connected to 14v (other than at the base) cannot have an output higher than 14v.

I think the 'charging system' data is poorly written, and refers to the nominal DC output, not the AC output.

TTR Ignition Systems - Teaching Old Bikes New Tricks
Shift Sensors - Quick Shift Controllers
Plug 'n' Play Quick Shifter Kits for FJ-09 US$150 + $15 shipping - In Stock
North American Distributor for Shifting ContRoll     Email
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1 minute ago, TTR Ignition said:

Only if it's connected to a higher-voltage source. A transistor (or mosfet) connected to 14v (other than at the base) cannot have an output higher than 14v.

Well i mean, who's to say if they aren't using a setup circuit and sacrificing some amperage, but I don't think that's worth their money/effort.

1 minute ago, TTR Ignition said:

I think the 'charging system' data is poorly written, and refers to the nominal DC output, not the AC output.

Agreed but can't assume.

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The stator open circuit voltage (no load) is >60VAC at 5000 rpm.

With a shunt-style regulator, you will observe stator voltage ~14VAC in low or full loads since regulator shorts out some cycles of stator output to maintain 14VDC output.

With a series-style regulator, the stator output is ~14VAC at maximum load. However at low loads, some cycles of ~60VAC (~5K rpm) can be observed at stator coil output since the regular "disconnects" the stator from load to maintain DC regulation and the stator coil is open circuit at that moment.

FJ09/tracer uses shunt style regulator.

 

Edited by ruenjou
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1 hour ago, ruenjou said:

FJ09/tracer uses shunt style regulator.

You would think it would be more efficient to open the coil vs sinking the excess?
What's the reason to do this on a modern bike?

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