I've documented round 2 of my electric bilge pump saga online. This version was made last year and has been tested thoroughly. My first iteration used an AGM battery and an electric switch. The battery was taking up space in the rear compartment and the electric switch failed (mechanically, not by flooding). I replaced the battery with a set of 12 NiMH AA in series and the switch with an air button and air switch - the kind used on hot tubs and spas. Details at: http://www.greatlakeskayaker.ca/pump.html Mike *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
On 12 Apr 2005 at 15:25, Keith Wrage wrote: > A couple of questions: What kind of operational duty can > you expect from a set of fully charged batteries? What is the non-use > discharge rate (e.g., if left sitting in your boat for 3 weeks, could > expect the pump to empty your boat 6 times?). The batteries I bought are 2300mAh NiMH. The complete set, therefore is 14.4V 2.3Ah. Since my bilge pump draws 0.9A at peak (measured from my Attwood 625 - most pumps are less efficient), that means I can expect: 2.3Ah/0.9A = 2.6 hours of operation. Realistically, the batteries are probably over-rated (most AA NiMH are according to one of the digital camera web sites). As such, I'd expect at least 1.5-2 hours of operation. Since it takes 3-5 minutes to empty the kayak (not a full cockpit, but typical of a wet exit) then I've got the ability to easily do 25-30 pumpouts on a single recharge. The discharge rate is roughly 0.4C, so I don't expect that the time available is reduced significantly by a high current draw. The worst case that I've done is three pool sessions over two weeks and about 6-10 pumpouts per session on a single charge. Most pumpouts were less than 3 minutes, though. There was lots of capacity left, if short recharge times are an indication. After a month on the shelf, you can expect the batteries to have about 60% of their full capacity. That means about 15-18 pumpouts. Mike *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
On Tuesday 12 April 2005 21.05, Mike wrote: > I've documented round 2 of my electric bilge pump saga online. This > version was made last year and has been tested thoroughly. (snip) > I replaced the battery with a set of 12 NiMH AA in series and the > switch with an air button and air switch - the kind used on hot tubs > and spas. Details at: > > http://www.greatlakeskayaker.ca/pump.html The battery holders you use are not known for their reliability! And they can rust as well! Better solder a pack from the variant of the batteries that we modelers use; we hate power failures - a model airplane without power can be lethal! My bilge pump is controlled by a switch, normally sold for turning off and on power on boats. I injected a little oil and sealed the terminals - works very well (even if my setup is a bit clumsy - I still use an SLA)! A problem with NiMHs or NiCads are their relatively fast self-discharging - NiCads should never be topped off, while NiMHs don't mind, as long as they don't get overcharged. Neither should be trickle-charged! SLA, like all lead-acid batteries, love trickle charge! Lithiums are actually the best for standby use, like a bilge pump, as they self-discharge very, very slowly (NiMHs are worst in that respect). For my setup see: http://foldingkayaks.org/gallery/tord and click on the bilge pump! New photos and texts, by the way! *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
On 12 Apr 2005 at 23:47, Tord Eriksson wrote: > The battery holders you use are not known for their > reliability! And they can rust as well! I'm not worried about rust, as the box is completely waterproof and most of my paddling is in fresh water. If I can get one that holds the batteries in place better, it'll be fine. > Better solder a pack from the variant of the batteries > that we modelers use; we hate power failures - > a model airplane without power can be lethal! That would prevent me from using a generic AA smart charger - I'd have to switch to a higher voltage charger. > Lithiums are actually the best for standby use, like a > bilge pump, as they self-discharge very, very slowly (NiMHs > are worst in that respect). My usage allows for relatively frequent recharge. I'm not worried about long-term storage and use. I play around with rolling a lot and frequently pump out the kayak. A long trip for me is one week, so self-discharge is not an issue. BTW - I always carry a manual pump or baler as a backup. Mike *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
Mike wrote: - >I replaced the battery with a set of 12 NiMH >AA in series and the switch with an air button >and air switch Tord Eriksson wrote: - >My bilge pump is controlled by a switch, >normally sold for turning off and on power >on boats. I injected a little oil and sealed >the terminals G'Day, I've tried both methods, three sealed electric switches and one air operated switch. The air operated switch was simpler to install and neater loooking. I was only able to try one air switch as it hasn't failed after a year and a half of operation. All the best, PeterO *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
I too have used a hot tub air switch and am very happy with the result - low profile on deck and no worries about water. I have used a sealed lead acid battery (2.9 Ah) for power. *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
Hello Mike, I'm getting ready to install an Attwood V625 in my kayak - basically duplicating your system, oh Mighty One! (since you've done the trial and error). I've got a couple of questions: 1. Would the inline check valve still be preferrable to the curly-Q-in-the-hose idea that came up later in the disscussion around this? 2. How's the air button/switch holding up over time? Is this still the way you would go? If not, any other ideas? All advice gratefully received. Cheers, Philip *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
kayakwriter_at_aim.com wrote: > I'm getting ready to install an Attwood V625 in my kayak - basically > duplicating your system, oh Mighty One! (since you've done the trial and > error). I've got a couple of questions: > > 1. Would the inline check valve still be preferrable to the > curly-Q-in-the-hose idea that came up later in the disscussion around this? Based on price and the functionality of what others I know are getting, I'd say use the loop-the-loop. The check valve has a rare but occasional maintenance problem - junk getting stuck in the duck lips and letting the valve leak. > 2. How's the air button/switch holding up over time? Is this still the > way you would go? If not, any other ideas? I have had few problems with this system. The air button and air switch themselves are not a problem. The only issue is that if you repeatedly remove the hose from the connector to remove the battery, the hose gets loose. It's relatively cheap to replace with a new hose. I initially had a problem with the battery holders not holding the batteries tightly. I replaced them with new, better ones (same design, better implementation, slightly higher price - different surplus store :-). With a bit of foam to hold everything snug in the little Peli-box, I've had no battery problems since. The only outstanding problem is with the pump mount. The base has two sets of locking tabs to hold the pump body in place. The outer ones have all failed by fatigue and broken off, so the pump is only held in place by the inner ones, which are not as tight. As a result, I can bump the pump off its base. If I was energetic, I'd replace the base. Mike *************************************************************************** PaddleWise Paddling Mailing List - Any opinions or suggestions expressed here are solely those of the writer(s). You must assume the entire responsibility for reliance upon them. All postings copyright the author. Submissions: PaddleWise_at_PaddleWise.net Subscriptions: PaddleWise-request_at_PaddleWise.net Website: http://www.paddlewise.net/ ***************************************************************************
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