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steve.sharratt

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  • Gender
    Male
  • Location
    UK
  • Occupation
    Consultant
  • Boat Name
    Nautilus

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  1. Nope, its probably me! I thought it meant that it would spin but not engage the alternator. Still a good question to ask though. The regulator manual does talk about cutting power (can’t remember exactly the circumstances) but I wondered how the alternator would react to a sudden loss of demand. I assume the regulator would have some sort of microsecond wind down?
  2. As part of the install, I am including the Balmar MC624 regulator which includes alternator and battery temp sensors. I read the install guide today and the system does control loads at startup, ramps up to max, can be programmed etc. It also has a ‘small engine’ feature which will 1/2 the operating parameters when the engine has other priorities. I think it simply shorts the alternator temp sensor and tricks it into an overload mode. I have gone back to the Balmar rep with several questions including whether freewheeling is achievable if output is not required. (I think he is beginning to hate me!) My engine is mounted midships and I always run with both side hatches open so temp doesn’t vary too much to what is outside. The engine doesn’t run very hot either.
  3. The alternator will be mounted separate from the engine but it is a narrowboat so it will never be too far away 😳! I will need to design a new alternator mount anyway so I can include an idler pulley. The installation will include a multi-stage controller as part of the setup.
  4. The flywheel is 23in so I assume this will be within the parameters of acceptable. The alternator is 24v and I believe the pulley is a 6 rib but have asked Balmar for more detail.
  5. Agreed. I read that it could be done but didn’t give it much thought. Rough side down it is!
  6. I think a polyV (serpentine?) should work and I know you can reverse them and use the smooth side. I have also checked the Balmar Output curves chart and I think I will be able to get the rpm high enough to make it workable at around 70amps at idle. The upside of the PolyV is that the Balmar pulley is smaller (than the double V) which adds to the rpm. My math is this: Currently: Using a double v pulley onto the engine pulley is 2.2in / 15.5in = 0.142 velocity ratio. 300rpm (engine idle) / 0.142 = 2112 rpm at alternator. Flywheel: PolyV pulley onto engine flywheel is 1.9 / 23in = 0.083. 300rpm / 0.083 = 3615 rpm. That takes it from around 20 amp to 70 amps at idle. 65 amps to 135 amps at running speed. That’s looking good. Just need to take some measurements now.
  7. It is! Although I don’t think it is a marine version. The original builder just set it up with the flywheel to the front.
  8. I did consider doing this originally as then I could use a serpentine belt. I dropped the idea when Balmar told me the 140a will run with double V belts which would work with the engine pulley. This was before I realised that I couldn’t achieve the revs. I will measure the flywheel to see how much more it gives. A simple solution to the problem if the flywheel is big enough
  9. Hi, I am looking at installing a Balmar 140amp alternator to charge my lithium house bank. I have a Lister JP3 and unfortunately the slow revs and pulley size is not sufficient to spin the alternator fast enough. Ideally, I need the alternator rpm to 5-6000 but my calculations suggest that I will only achieve around 2500rpm (engine revs of 3-500rpm). This gives a amp output of 30-50 at best. I am toying with the idea of engineering a ‘geared pulley’ between the alt and engine. e.g. 15-16in engine pulley to 2 in pulley currently gives 2500rpm. If I place a intermediate 2in pulley which is attached to a 4in pulley to the alternator, this should theoretically double the alt speed to 5000rpm. The math is probably a bit rough but is used as an example. Has anyone overcome the problem of slow revs? I would love to hear how you solved it. Chers
  10. That is interesting and I think that’s what the engineer who did recent work on the box was talking about. Do you have a recommended supplier and a rough cost?
  11. I have seen two basic options - one is the PRM soft shift which looks similar to the standard valve block (see ASAP Supplies options). The other is the Beta Marine accumulator (Dintra) which has the two accumulators on top that you mention. I have revised my description to Clunk, rather than crunch, based on TB’s comment. I am confident that the system is in good order as I recently had a lot of work done on the box. I have a midships engine so a long prop shaft and I am spinning a 25” prop so that probably isn’t helping. Some sort of soft shift device is most likely the answer. I am waiting on some feedback from PRM and will make a decision whether to go with them or the Beta Marine option. Both around the £4-500 mark. Ouch!
  12. To be fair, it is more of a clunk than a crunch - either way its a big clunk and bloody annoying! My box was recently disassembled and it is in new condition with no signs of wear so I am confident that the box itself is ok.
  13. Hi, I know this thread is a bit old but I am currently trying to resolve my crunching issues on my PRM500. I see that a soft shift valve works but I am curious to know whether this has been used on a slower revving engine. I have my suspicions that my Lister JP3 is idling too low (300rpm) and this is causing the crunch. This is opposite to the high-rev scenario and I wonder whether the slow shift will work in my case. The valve block I currently have looks identical to the soft-shift version so I am not even sure if it is already fitted or the valve block just look very similar. Currently waiting on some advise through ASAP Supplies who are talking to PRM. Figured it would be worth asking the ‘real world’ in the meantime. Cheers PS. Has anyone tried the Beta Marine accumulator option. They mention them on their website but don’t provide a parts option?
  14. Thanks for all of the helpful comments. I have decided to go through Brentford rather than down to Limehouse and have started planning accordingly. I have checked out the bookable moorings so have a few o/n stops sorted but note that there seems to be a big gap for suitable moorings when turning on to the Paddington Arm. My dog has imposed a 3-hour cruising limit so I tend to stick to that for planning purposes. This is my plan, so far: D1. Teddington to moorings below Hanwell (Norwood?) locks. D2. Uxbridge Rd Moorings D3. Paddington Basin. D4 - on. Suck it and see? I have now decided to try the rivers Lee and Stort so any advice would be appreciated. If the weather holds, I may head back down the Paddington arm or through Limehouse and do the Thames run back up river. I probably wont set of until EOM due to other commitments. Cheers Steve
  15. That’s a kind offer, thanks Tony. I have called Kev? and he has been very helpful but unfortunately specialises in 12v systems. He is still able to test, to at least ensure it is functioning. I have sent him some pictures (which I will add to this post). Cheers
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