>That all said, it seems like you are saying one can never rely on their gauges? If that's true, these craft seem quite dangerous by design.
“quite dangerous by design”…hmm…does your car include a fuel gauge that tells you reliably how much time you have left to drive?
No? Yet you still drive the car anyway. Would you say that the car is also “quite dangerous by design” then?
A bit of info for you: First, your client’s boat likely has lead acid batteries. Depending on how your client and the previous owner of his boat treated those batteries, the fully charged capacity they actually have could be anywhere from 30 - 100% of the rated capacity. That’s a wide range. Further, your client may not know how to properly operate the charger or perhaps has the impression that charging for 1hr is enough---I have a friend that never trusted his charger to leave it plugged in overnight, so I know this happens. Further still, of the 6 or 12 batteries that are in the boat, there may be some real losers that severely limit the discharge time and range. And it only gets worse with time.
The meters themselves vary and I haven’t a clue whether the boat in question uses a Link10 style meter or some in-house design or what. In the case of a Xantrex Link-10, the only way to depend at all on the “time remaining” readout is if you have manually set the battery capacity parameter appropriately for your pack. So if, as in my case, you have some seriously old batteries which are rated for 225ah, yet probably are only good for 80ah, to at all believe the “time remaining” readout, you’d need to select 80ah or so for the capacity parameter in the meter. Failing to do that, the ‘time remaining’ readout on the boat is largely meaningless as it hasn’t a real clue how much capacity the pack has. It could infer it by reading how much charge was brought in at the last few charge cycles and noting the depth of charge in each case prior, but I doubt it does that.
Now, does this meter make the boat unsafe? Of course not! For one thing, any such meter that includes a ‘time remaining’ display likely also allows the user to view Battery Voltage, Battery Current and most important, Charge/Discharge in Amp-Hours. That last one is your best gauge to know how far or how long you can run---i.e. if your last outing ended up with the gauge reading -140ah and you still had a voltage that wasn’t near the 1.75v/cell level, then after a full recharge, you’d expect that the next outing could similarly deliver 140ah. And at a steady 40amps of cruise current, you’d have some level of confidence that you’re good for at least 3hrs of such cruising. I don’t think you’ll find many people on this list who leave their meters on the ‘time remaining’ readout---to do so trusts that the SW in the meter that predicts this has the right parameters and data to figure this out.
Sure, your client may have a defective gauge. But having been on this forum now for some 8yrs, I don’t think I’ve ever heard of Duffy owners chiming in about defective gauges or “dangerous duffies” and so I don’t think you’ll develop a case from this list. I can tell you this: If your client’s meter is a Link-10 and if they monkeyed around with the battery pack wiring, there’s a good chance they could have fried the current sense inputs on the gauge. The result is that such a gauge delivers no meaningful current information and without that, no meaningful AH or Time info. This has happened to a lot of owners of these meters and there are more unsafe ways to wire up and power up these gauges than safe ways. In my case, I have a single connector for all the connections to my meter---I don’t take chances as it is a known defective and unforgiving design. Any time I contemplate removing battery cables or rerouting wires, I pull the plug to the meter to keep it safe.
Anyway, we know too little about your situation to help really. But if you and your client think that his boat is unsafe because of an inaccurate depletion predictor gauge, I’d suggest taking some boater’s safety and basic electricity courses instead.
-mt
From: electricboats@yahoogroups.com [mailto:electricboats@yahoogroups.com] On Behalf Of barristerla
Sent: Thursday, December 16, 2010 8:51 PM
To: electricboats@yahoogroups.com
Subject: Re: [Electric Boats] New member, Q re: Duffy Boat
Dear Rick and Mark,
Thank you for your insight.
I think the main issue with this gentleman is that the gauge always seems to be inaccurate, even when fully powered, so, when it says it has 2.5 hours remaining, he is never sure what he's got. The representation from Duffy as to the efficacy of the gauge was quite different.
That all said, it seems like you are saying one can never rely on their gauges? If that's true, these craft seem quite dangerous by design.
George, as to the advice re: a qualified technician, the boat manufacturer warranties the boat and this item, but refuses to fix. I should note, your tone is not appreciated...
Regards,
Scott Kaufman
--- In electricboats@yahoogroups.com, GeoMar Logistics <geomarlogistics@...> wrote:
>
> *Go away. Tell your client to suck it up, stop whining and get a qualified
> electrician to trouble shoot the problem. *
> On Fri, Dec 17, 2010 at 7:16 AM, barristerla <no_reply@yahoogroups.com>wrote:
>
> >
> >
> > Hi folks:
> >
> > I'm new to the group. As you may have guessed by my "handle" I am an
> > attorney. I am NOT, repeat, am NOT looking for business here.
> > I could use some input from you folks though.
> >
> > I currently have a client who claims to have issues with his2008 Duffy 18
> > Snug Harbor craft. More specifically, he claims that he has issues with the
> > readout on his Digital Energy Gauge. It does not appear to show the proper
> > time remaining even when initially charged and going forward, during use. He
> > feels he cannot depend on it and if he did he may end up stranded at sea.
> >
> > I have searched the net and not really seen any other folks having these
> > problems. Are any of you experiencing this issue or do you know anyone who
> > is? Usually I expect at least some smoke before I believe there is a fire...
> >
> > Thanks in advance for your thoughtful responses.
> >
> > Regards,
> >
> > Scott Kaufman
> >
> >
> >
>
>
>
> --
> *George Johnson
> GeoMar Logistics
> Jomtien, Chonburi
> Thailand*
>
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