[electricboats] Electric Drive Installation - Regen and Shunt Meter

I have been progressing with testing and tweaking of my new electric drive system.  I have some mods to the cooling system in the works. 

Today I installed a shunt type battery meter (Victron 712) to get a definitive look at current flow in and out of the battery.  I collected some data and I'll have that later.  In the mean time I have some encouraging results from testing the regen capabilities.  

I was sailing in 8-11 knots making 5 knots and I set the motor speed at about 300 RPM and was generating about 130 watts into the batteries according to the Victron meter.  This is quite a bit better than I expected at this moderate wind speed and moderate boat speed.   The 18" propeller probably helps with this.   I estimate the regen was costing about 1/2 to 3/4 knot of boat speed.  I was only flying my main and a working jib and was sailing on a close reach to beam reach.   It looks like I may have a chance to try this out in wind enough for hull speed in a few days.  I'll report back if I do. 

I should have started out with one of these shunt type meters.  The instrumentation that Thunderstruck provides through the CAN translator reading from the controller is good but the shunt meter is more definitive as to what is going in/out of the battery.  The Victron unit I have has many nice features the most useful of which is probably the time to empty display. 

More to come...

Dan Pfeiffer


BOAT DETAILS
Pearson 10M
33' LOA
28.33' LWL
12,500 lbs
48V 280AH LiFePo4 battery
Sevcon Gen 4 Controller
Motenergy ME1616 w/3:1 belt drive reduction
J Prop 18" 3-blade feathering prop
Victron 712 battery monitor