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I'm going to try to answer a bunch of questions in the same post, so
am threading it to be under my original post which spawned the Amps discussion. Due to the multiple responses, this is pretty long (surprise! Mine are *never* long :{)) ) From: Lew Hodgett Skip Gundlach wrote: We don't yet know. We're going to do an energy audit, prolly tomorrow, to see just exactly how much each item uses. Add battery capacity, any way you can, it solves a lot of problems including poor alternator performance. Lew We've already got massive batteries. The issue is properly keeping them charged. At 750 nominal (less aging) AH, we can go for a long time with no charge input. But if we don't put in the charge, eventually the biggest battery bank will be flat, even if nothing is drawn from it, out of normal charge dissapation (flooded = ?%/ month)... From: Bob On Jul 23, 8:45 pm, Lew Hodgett wrote: Skip Gundlach wrote: We don't yet know. We're gong to do an energy audit, prolly tomorrow, to see just exactly how much each item uses. Add battery capacity, any way you can, it solves a lot of problems including poor alternator performance. Lew There is another path............. reduce load = smaller house bank, smaller battery charger, smaller alt, less engine running, quiter, cooler, also less things to fix! Bigger aint always better. My 400 Ah house bank is huge............... for me ![]() We will be carefully monitoring our use once we get our audit finished. We *believe* (time will tell) that we'll have ample charging available for the uses we need to put our load to. From: Bob On Jul 23, 8:00 pm, Skip Gundlach wrote: On Jul 23, 12:59 pm, Bob wrote: Hi Skip: Do you have a way to determin a battery's level of charge? Battery Monitor? Hydrometer? Bob Actually, all of the above: We have a TriMetric 2020 monitor, by Bogart Engineering, which provides a lot of information. Volts, amps in or out, state of charge in percentage terms are all front-and-center. Menus allow time from equalization, AH left, current state of AH up or down in numerical terms, time from and what is low and high (two separate measures), and so on. Our controller for the KISS wind generator (in addition to the on/off control of the generator itself) is a Xantrex 40A unit. When it's piping outside, we can get close to 30A before the internal controls shut down, but it doesn't start producing meaningful amps until ~15knots (designed for the Caribbean market). It's whisper quiet in our setup; YMMV dependent on how well you balance the blades. At full charge, that controller diverts to a heat strip setup, required because our water heater wouldn't accept the dual voltage unit where we used to send overcharging before we replaced the water heater. We have not yet installed (because we can't find where we stored them) an incandescent monitor lamp so that if that's happening we can hurry and turn on charging loads for AC devices, taking advantage of the overstock of amps. Our controller for the 370W of high-voltage Solar is a Blue Sky 6024H MPPT, which provides as much as 30% more than the rated values of our panels. At 9AM in Charleston, we typically show 12-15A, and at best, sometimes as much as 25A in mid-day. That controller just turns off the load (open- circuits the panels, I think is what's happening) when they're full. It also has an equalizer button, but with 750AH, it's unlikely we'll ever see enough amperage to actually accomplish that, even connected to shore power. We also have a battery conditioner attached - it uses the battery's own power to pulse, helping prevent/minimize sulphation. The very long- cycle charge regime of the solar and wind has meant that we very rarely see less than "full" on the monitor. Making sure we see above 13V nearly all the time we're not running huge loads is the bigger deal... Our new shoreside battery charger is a Xantrex TrueCharge40A unit. We have 4 L16H in series/parallel 12V, plus the windlass and starter batteries separated on an isolator. The shore charger, plus whatever solar and wind input has occurred since the TC40 installation has brought us back to full, with SGs previously in the 1.250 range to over 1.265 in all cells and no large variance (65, 65, 70, 75, 75, 75, 85, 80, 90, 80, 75, 75 in the 12 cells) either from cell to cell or in individual batteries. We have no remaining halogen bulbs (haven't taken out the foredeck light; might be one in there) due to their current draw. All on board lighting is either fluorescent or LED, outside is either LED or the afore-debated incandescent running/steaming lights left so because of "all the current available during engine operation" - which I may have to re- evaluate... From: Lew Hodgett Bob wrote: There is another path............. reduce load = smaller house bank, smaller battery charger, smaller alt, less engine running, quiter, cooler, also less things to fix! Bigger aint always better. My 400 Ah house bank is huge............... for me ![]() As long as you remember that you must replace 125AH for every 100AH consumed and the max sustained recharge rate is 15% of the battery bank AH capacity. Being realistic, over time, electrical consumption will increase, not decrease. These days, minimalists are few and far between. Heh. Guilty as charged (pardon the expression). But, we believed that we provided for that in our initial design. It proved that we were dependent on a charging source (the prior 70A NewMar beast) which wasn't happening. We'd not have behaved as we did onshore, at the hook. That we discovered our alternator simultaneous problem, we feel, now that it's corrected (more below), that the shore and engine charging parts are up to snuff. From: Skip, I strongly suggest that you get a digital voltmeter with at least one decimil place readout and wire it into your system. Use a selector switch so that you can read the voltage of any battery bank. It is priceless for monitoring what is going on with the electrons. The one I have is a LED readout so it is easy to see at night. You can use it to check everything - charging? It will climb up to about 14.4 volts and then drop off to about 13.6, or if you are using a manual charger you can monitor voltages and switch the charger at the appropriate time. How much power are your nav lights using just switch them on and check the voltage. Ho! Ho! Turned the lights on and the voltage driopped 0.1 volts at 12.7 volts. A little math and you know how much power yout lights draw. We have such a meter, but have not wired it in. It's part of a multimeter that I use all the time. It's what I used to determine that the alternator shop had mis-ended (male instead of female) the tach lead on the new 94A unit. OTOH, we have a pretty good one in the TriMetric, also digital, with 10ths in both amps and volts. We keep an eagle eye on it... When we put in the new alternator, we (with a full battery bank) shut off the shore charger, turned on the inverter, and loaded up absolutely everything we could on the boat. Inverter with all the electrical stuff we could find (two computers, all the charging equipment for handhelds, three fans, etc.). Every single instrument and light, in and out. All the pumps rated for continuous duty, with salt and fresh water taps left open. All the AC and DC fans, engine room and otherwise. The one single remaining incandescent wall fixture. The fuel polisher and reefer, etc. We managed to create just under 50A of load. Short of transmitting on the SSB/Ham (we did it in standby, for only 2A), that's the worst it can possibly get with no outside input. Of course, letting it go like that, for an extended period of time, even with the capacity of our bank, would be very hard on the battery were there no input. So, after letting it consume about 15AH (per the TriMetric), we cranked up the alternator. WhoooEEEE! The meter went from -48 to +40, and slowly started to come down. The battery voltage, which, by now, had been down to about 12.1 due to all the drop, steadily climbed. It quite quickly reached well over 13, and kept climbing. Of course, that's also way more drop than we'd likely get before we did something about the load, but it was very reassuring to see that not only could we sustain that load at about 1500RPM, but put as much back in as our shore power charger would in a no-load situation. So, once we'd proven the point, we shut down most of the loads other than the computers which were both on (connected to shorepower otherwise), and saw the voltage immediately charge rate climb, level off, and then start to taper. We got to 14.4 and things started to calm down. Having proven *that* point, we shut it down to keep the temps in the boat somewhat reasonable, and reconnected the shore power. The batteries were recovered (14.4, then equalibrium at 13.3, with the shore power cycling occasionally, and the solar cycling in and out as well, providing ~10A at that time of day, when it wasn't full. Significantly, the radar didn't drop out when we started the engine, whereas it always had before. Seatrialing the instruments is next, but I'm convinced that our problems will either be entirely, or mostly, resolved with the proper application of power. As it is, my freezer is well under spec, running so fast that the evaporator briefly acts as a cold plate, resulting in an under-temp spec (it comes up relatively quickly to the set temp), where we've been struggling to keep it under freezing, let alone the 4 or 5 it is now (set point 8, 2* hysteresis). From: Pete C On Jul 24, 5:46 am, Bob wrote: On Jul 23, 8:00 pm, Skip Gundlach wrote: On Jul 23, 12:59 pm, Bob wrote: Hi Skip: Do you have a way to determin a battery's level of charge? Battery Monitor? Hydrometer? Bob Somehow I think Skip would prefer to spend time writing lengthy cruising blogs, than learning about S.G. levels... =) Hm. How many times do I have to sample to earn my merit badge? In 5 days I've been in Charleston, I've done it 3 times. :{)) From: RW Salnick Jeff brought forth on stone tablets: BTW, I agree about the DVM, its essential on any boat that has more than a minimal electrical system. Better yet is an Amp-hour meter, certainly pricey but worth every penny if you have larger loads, such as a fridge, and tend to live off-grid. I second the comment that you need a way to monitor amp-hours in and out of your batteries - it is the only real "fuel gauge" for batteries that there is. And it is essential if you are not living plugged into shore power. We have a Link 2000 and I absolutely love it. I *think* I have such in the TriMetric... That ought to hold us for a while. I'd bother the librarian but Lydia would complain - and, besides, I'd rather write :{)) Well, no. I'm changing my tag line on the skype and googlechats to "I'm in the engine room, but try anyway - I may hear it" - it used to be that I was in the bilge. Hands, please, for those who have spent more than 100 hours in their engine rooms in the last month - I have - in addition to doing the research and running around to fix those things which have cropped up (Roger, I know you qualified last year)... PS to Geoff - has the above eased your concerns about our instruments? It's why we're still here... L8R Skip Morgan 461 #2 SV Flying Pig KI4MPC See our galleries at www.justpickone.org/skip/gallery ! Follow us at http://groups.google.com/group/flyingpiglog and/or http://groups.yahoo.com/group/TheFlyingPigLog "Twenty years from now you will be more disappointed by the things you didn't do than by the ones you did do. So throw off the bowlines. Sail away from the safe harbor. Catch the trade winds in your sails. Explore. Dream. Discover." - Mark Twain |