A couple points:
1) The standard ol' ETEK is rated at 48v, 8HP----not sure where the 36v rating you refer to comes from…I ran with a 36v PbA pack for 10 years (from mid 2003 until late 2013). My lithium batteries charge to 48v and are depleted completely at 31v. The lithium pack is Uber-stiff in terms of voltage---even with 1 fully charged battery, I could pull 200amps at 48v from the battery at full throttle without the battery flinching. Right now I have 7 batteries in parallel and will eventually have 10. I could see going to a 96v system at some point if there were good reasons to do so. In the meantime, I'm still running with the same 1st set of brushes on this motor with 2 spare sets…
2) Added weight and range: I've run with as little as 180# and as much as 800# (2 strings of 36v T-105) over the years. I didn't like 800# of batteries in the back and the boat didn't sit well in the water. With lithium, I'm able to spread the pack out fore- and aft- without having to vent the batteries during charging, so going with 800+# of lithium and the added displacement isn't that big of a deal. OTOH, even a 420ah pack would be better than the old lead acid pack I had---I don't really need 2x this…however, with 840ah and my typical usage, I don't think I'll be hauling around a genset except once every couple years, if that. It's crazy---on a full charge, I could run 9 hours at 80amps (5kts) and do 45-nmi…with that kind of range I probably should host the West Coast version of the Wye Island Challenge by offering a race around Sauvie's Island on the Columbia River…that's probably about 43 miles---but then, who wants to motor for 9 hours straight? J Certainly not my ETEK.
Are you sure you displace 1800#/inch? For my hull, it's about 700#/inH20…
-Myles
From: electricboats@yahoogroups.com [mailto:electricboats@yahoogroups.com]
Sent: Saturday, November 7, 2015 3:38 PM
To: electricboats@yahoogroups.com
Subject: RE: [Electric Boats] Looking for a great fishing story!
A 41v nominal pack voltage denotes your really honing in on the 36v aspect of your motors still I assume to be the same as my footprint being an old etek. Mine actually say 36v on the motors themselves. So I was a little shocked to say the least when I opened them up but apparently they do well way beyond 36v.
Besides I guess a mont709 is the direct replacement more or less so affordable electrical is where it is at. If I'm reading your configuration right you simply flick a switch to go from 48v to 36v which is a very effective controller. Do you have reverse?
Our boats are of a very similar displacement and construction mine being plywood epoxy as well. I estimate that I'm 3500lbs bone dry as in 12 years on the dry.
That is exactly the scenario that is playing out for me as well regarding obtaining and upgrading lithium. It was suggested by the vendor to simply buy a lesser pack and see how the weighting works out with the boat and then if need be double the pack size later on if needed or wanted.
I'm weighing in at around 530lbs for my 400ah 48v pack. Truth be told though with all the other gear I'm probably adding more like 1200lbs on to the final dry weight when it gets picked up in the slings. I'm hoping the travel lift has a guage on it to weigh me.
Are you concerned with the added weight in relation to expected returns or has your experience absolved you of all the range anxiety you may have?
I know roughly that every 1800lbs or so I drop an inch at the waterline.
Arden
Posted by: "Myles Twete" <matwete@comcast.net>
| Reply via web post | • | Reply to sender | • | Reply to group | • | Start a New Topic | • | Messages in this topic (3) |
No comments:
Post a Comment