I purchased and installed an alternator kit from Breezeworks a short time ago. I believe it is called a three wire alternator.
There have been some discussions in the forums here about how the alternator should be connected into the electrical system of a 470 powered boat.
The directions from Breezeworks instructs connecting the black (ignition) wire to the coil + terminal.
On our boats this coil terminal is at a reduced voltage due the the resistance wire. (My system still uses old fashion points, so resistance wire is still in place).
People here on this site advocate connecting the alternators black wire to a wire that has a constant 12 volts to it; such as the wire going to the choke before it connects to the resistance wire. Connected this way, the alternator would have a full 12 volts available to it.
For my installation, I connected the black alternator wire to the coil + terminal.
After reading about connecting the wire to 12 volts, I thought maybe because mine is not connected that way, my system may not be performing at 100% capability.
Had some spare time, so thought I would take some measurements with the black alternator wire connected to both places independently.
I found that it made no difference where the wire was connected as to how well the alternator performed.
At 600-700 rpm, I was seeing about 14.74 volts to the batteries with the black wire connected to either place.
What about charging capabilities (current delivery)?
Both my batteries are in pretty good shape charge wise, so I didn't expect to see much alternator charge current being needed.
My battery switch has both batteries connected in parallel for these tests.
A DC current clamp around the alternators output wire was used to measure charge current.
Measured 7-9 amps at idle speed of 600-700 rpm.
Trim up/down motor utilized to place a larger current demand on the system..measured 27-28 amps again at idle speed 600-700 rpm
Upped engine rpm to 1000 and measured 56 amps using the trim motor as a load.
upped rpm to 1500 and measured about 66 amps trim motor as a load.
The same results were achieved with the black alternator wire connected to the coil + terminal, or to the 12 volt wire at the choke.
For my installation, it appears the black alternator wire can be connected to either place and the alternator performance is the same.
The original charging system (stator system) was only rated at 35 amps full output; this explains why after a day of many starts/stops, due sking/tubing, my battery always seemed to not be fully charged.
This system puts out almost that much even at idle!!
There have been some discussions in the forums here about how the alternator should be connected into the electrical system of a 470 powered boat.
The directions from Breezeworks instructs connecting the black (ignition) wire to the coil + terminal.
On our boats this coil terminal is at a reduced voltage due the the resistance wire. (My system still uses old fashion points, so resistance wire is still in place).
People here on this site advocate connecting the alternators black wire to a wire that has a constant 12 volts to it; such as the wire going to the choke before it connects to the resistance wire. Connected this way, the alternator would have a full 12 volts available to it.
For my installation, I connected the black alternator wire to the coil + terminal.
After reading about connecting the wire to 12 volts, I thought maybe because mine is not connected that way, my system may not be performing at 100% capability.
Had some spare time, so thought I would take some measurements with the black alternator wire connected to both places independently.
I found that it made no difference where the wire was connected as to how well the alternator performed.
At 600-700 rpm, I was seeing about 14.74 volts to the batteries with the black wire connected to either place.
What about charging capabilities (current delivery)?
Both my batteries are in pretty good shape charge wise, so I didn't expect to see much alternator charge current being needed.
My battery switch has both batteries connected in parallel for these tests.
A DC current clamp around the alternators output wire was used to measure charge current.
Measured 7-9 amps at idle speed of 600-700 rpm.
Trim up/down motor utilized to place a larger current demand on the system..measured 27-28 amps again at idle speed 600-700 rpm
Upped engine rpm to 1000 and measured 56 amps using the trim motor as a load.
upped rpm to 1500 and measured about 66 amps trim motor as a load.
The same results were achieved with the black alternator wire connected to the coil + terminal, or to the 12 volt wire at the choke.
For my installation, it appears the black alternator wire can be connected to either place and the alternator performance is the same.
The original charging system (stator system) was only rated at 35 amps full output; this explains why after a day of many starts/stops, due sking/tubing, my battery always seemed to not be fully charged.
This system puts out almost that much even at idle!!
