Greetings all,
Wanted to share my successes and learnings with the 5kw Thunderstruck kit, using the Sevcon GEN4/size 4 control and the ME1305 motor.
I replaced what appears to be the original 2.5hp GE/Taylor Dunn 36V series wound brushed motor. This motor achieved 5.5mph at 2kw turning 3000RPM, with v-belt reduction 3:1 driving an eight inch three blade composite propeller. The motor compartment is small and mounted high under the captain's seat midship, and is unventilated. The motor easily reached 180F underway for an hour and smelled like insulation and ozone. The speed control was a Salzer four three pole four position (+ off) that switched the battery configuration between 6S1P 36V to 3S2P 18V.
I expanded the battery bank to 48V with two additional 6V batteries, so the total capacity is about 10.5kwh, and is measured with a Bayrite chinesium watthour meter.
The new ME1305 was installed in a custom aluminum box that supports the NEMA C 143T size motor, with ducted cooling to the inlet side of the motor. The ducts pull air from an aluminum heatsink enclosure that the Sevcon controller is mounted to.
Testing on the Vermilion bayou was a little tricky due to river current, but to achieve the same propeller revolutions the motor and controller required 1200W watts to reach 3000RPM, so using 40% less energy than before. This, combined with less amperage at 48V brought my underway discharge rate from 55A to 25A, a major Peukert win. I went from 85MPGe to 131MPGe (2.5mi/kwh to 3.9mi/kwh), not accounting for any Peukert gains.
Despite having twice the available HP, I can't really increase my speed. My target was to put the ME1305 at its peak efficiency range of 3000-3500RPM, and the motor performance curve falls off quickly at the upper end of this speed range, so WOT gets me 3625RPM at 32A (1.5kW), which looks like about 6mph. At 70F ambient, the controller makes no apparent heat, and the motor skin reaches 90F after several hours and 18 miles of river travel.
Very happy with the kit build quality and value. My only suggestions would be for them to mark CW/CCW on the ET134 directional control, and smaller ring terminals for the Sevcon end of the cables.
Next modification will be propeller optimization.
Posted by: benjatelcom@gmail.com
| Reply via web post | • | Reply to sender | • | Reply to group | • | Start a New Topic | • | Messages in this topic (1) |
No comments:
Post a Comment