Friday, December 26, 2008

Polychain Drive Belt

The latest modification to the AMPhibian: Gates polychain drive belt and sprockets.

I'm not sure if the sound in the video really shows the difference but now the motor brush noise is the dominant sound as opposed to the rattling of the chain and sprockets. The roller chain was already showing some stretch and it's been suggested that #50 chain under changing torque loads and speeds up to 6000 RPM is way beyond it's long term capacity so this should be a worthwhile modification even beyond the noise factor. Also I no longer have chain lube being sprayed around my motor and batteries.
Another possible benefit is I can get two more hubs for the taperlock sprockets which would allow me to swap them fairly easily and double my top speed to almost 40. I don't know if I'll bother since I have no need for that but it might be fun to try and the hubs are fairly cheap.

Tuesday, December 16, 2008

New Mod, portable 120 volt power supply

Trying to get the most out of the AMPhibian I wanted a way to utilize the power of my 48 volt DC battery pack in a 120 volt AC mode to run tools and provide some backup power for my house in case of an outage. You can buy 12 volt DC to 120 volt AC inverters but a 48 volt version isn't easy to find, or cheap. However I spoke to someone on the EVDL who gave me the idea to find an old computer back up power supply, or UPS, without batteries and use my pack. Since most larger UPS run off 48 volts this would be perfect for me. I picked up a used APC 2200 UPS without batteries for $160 shipped and hooked the battery inputs up to my 48 volt battery pack in the AMPhibian. I now have a portable 120 volt AC power supply with 1600 watt capacity. I was able to run my Makita electric chainsaw off it as a test tonight. Not sure for how long, but I should be able to drive into the woods, cut a tree into log lengths, and drag them home, all on electricity.