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From: (no name) (no email)
Date: Fri Apr 25 2008 - 18:58:00 EDT
Sounds like we should talk to Bob to understand the pulley options - if anyone knows that stuff, he would :) A toothed belt sounds interesting, and I received another reply about a replacement crankshaft pulley that is for an alternate alternator mounting (the belts only run from the crankshaft to the alternator, existing water pump and alternator stay as-is).
I'll look into the large frame, smaller output alternatives. It's not like we're trying to save space under the hood or anything :)
A few bits of context I left out....
We do have a Link 1000, comparing the net amps in to the alternator output is how I could see that most of the alternator output was going to DC loads rather than charging (and thus ensued some load management actions, including starting up the genny so we could remove inverter loads while running). The reason that we didn't notice the drain was it basically occurred overnight - when we woke up we saw that the Ah reading was waay down. Even then it was hard to trace to the ice maker (though it makes sense - duh). We had to be observing the current amp usage while the icemaker was in it's "use power" mode, which seems to vary during the time it is making ice. And to be honest, we didn't think our usage was that high, so we really weren't watching the accumulated Ah during the afternoon/evening to have a heads up that things were trending negatively. Lesson learned there, for sure. I'll probably change the settings so that the display doesn't sleep and either have it roll
or le
ave it on Ah most of the time, to be able to see things at a glance rather than plodding up to the pilothouse and pushing the button now and then (while at anchor).
Our wiring should be pretty up to snuff. Three battery banks - house, starting and genset starting. House is 6 x 6v (L-16HC) in series/parallel, starting is 2 x 12v in parallel (not 8D's :)) and genset starting is 1 x 12v. Alternators are connected to the main buss (in engine room) w/ 2/0 cable (thus they are in parallel) and also have a dedicated ground connection (alternator - mani ground buss via 2/0 cable), the main buss is connected to the house battery bank (in lazaret) via 2 x 4/0 cables (that's 2 pos and 2 neg). Starter batteries charged from main bus via a Balmar DuoCharge (provides up to 30A charging from DC source). Genset starting battery managed by genset alternator.
And you're right about the original wiring - I'm pretty sure it was #8 cable for the alternators that I replaced. :)
Thank you for the ideas :)
-- Jason Pringle M/V Shibui - 50' OA Mk I www.quartermasteryacht.com -------------- Original message ---------------------- From: "Mark Richter" <> > First, the advice to use the built-in diagnostics of the Balmar regulator is > spot-on. Try that first. > > The Lehman has a fairly fragile bearing on the water pump, according to > designer Bob Smith, which somewhat limits your charging options. Driving > alternators over 100-110 amps with a single 1/2" belt is problematic; you'll > have to adjust tension religiously and will still go through belts regularly > (like I do). Each broken belt is an opportunity for an engine overheat > incident (I have two alternators and two belts on my Deere). Have you asked > Bob whether they have toothed belt replacement sheaves for the 120? These > belts, sometimes called timing belts, work at higher torque levels with > lower tension, thus not endangering that water pump. The newer John Deeres > (not mine) have toothed belts, and can drive a large frame alternator > easily. > > Apparently, you don't have a battery monitor (Heart/Xantrex Link 10, 20, > 1000, 2000, XM or equivalent). This would be a great addition, as you would > have a reliable measure of the net input/outgoe to the batteries, and would > know how discharged the bank has become. > > Your note didn't say where the output of your two alternators goes. Do both > directly charge the house bank, or is one feeding a starting battery? How > large is the output cable from the altertnators to the battery, and how > long?. For short runs of 3-4 feet, #4 is adequate. Any longer, and you > need a #2 cable. In either case, be sure the insulation is rated at 105 C. > I've seen many Lehman alternators wired with #8 cable, and they aren't > always upgraded when a high-output alternator is substituted. Also be > careful that this cable is tied up securely and double-insulated (covered > with a hose) if it passes over any grounded engine parts. > > Don't write off large frame alternators so easily. My favorite alternator > guy, Vic's DC Electric in Stuart, FL (561-220-8952) can supply them down to > 100 amps for a lot loss than Balmars. They're more efficient than > small-frames, so require less torque to drive, and they last longer too. > Also, a larger one (say, 150 amps) driven with a larger diameter sheave will > be derated at lower RPM's, and larger sheaves are much easier on the belts. > > Let us know how it goes. > > Mark Richter, Mark's Mobile Marine > Electrical system design, installation and repair > usually in Ortona, FL on the Okeechobee Waterway > presently anchored in Wrightsville Beach and northbound _______________________________________________ http://lists.samurai.com/mailman/listinfo/trawlers-and-trawlering To unsubscribe or modify your subscription options (get password, change email address, etc) go to: http://lists.samurai.com/mailman/options/trawlers-and-trawlering Trawlers & Trawlering and T&T are trademarks of Water World Productions. Unauthorized use is prohibited.
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