Arnot

You could try disconnecting it from all power for about half an hour and trying again but I think it's telling you it wants a holiday in Holland... Regards Arnot

It's a thorny one this... The BSS manual says that a battery master switch must be fitted - and then goes on to say that there are a variety of circuits that can circumvent this providing they are fused. For my part, I tend to wire domestic alternators directly to the battery but is it a bit af a balance of risks as follows; 1) If the alternator is connected through the master switch. If it is inadvertently operated whilst the engine is running (or fails) there are two scenarios. In the case of a simple alternator it will possibly fubar it and probably not even down power the domestic circuits. In the case of a battery sensed alternator, it will probably fubar it and at the same time generate immense voltages and fubar almost anything else connected to the domestic circuit, there are some systems though that anticipate this possibility and have safety circuits buit in to prevent over voltage. However the safety element is that the switch can be operated and make the complete system safe to work on if the engine is off. 2) If the alternator is not connected through the master switch. There is little possibility of the problems oulined above - but - the casual owner may thnk that when the switch was in the "off" position the alternator wiring was safe and short circuit it whilst working in the engine. The current path for charging is more direct and has fewer connections which results in better reliability and better charging. Also, if the master switch is operated in case of an emergency then it really does kill the domestic circuits immediately. All that I can say is that acknowledging the BSS intention to promote boat safety, technically I have reservations about wiring the domestic alternator through a master switch. I have aften seen catastrophic failure and a lot of consequential damage as a result. The idea is that the operation of the master switch allows disconnection of the power from the system immediately but of course if the engine is running, the alternator just keeps on pumping it in. Finally, ask youself, if this is such an important safety issue, why don't they fit master switches to cars? Some vehicles do have a master switch but these tend to have auxilary contacts to switch off the alternator when it is operated. Regards Arnot

Merlin are on the right track but probably for the wrong reasons... A 440Ah leisure bank wont like taking more than about 88A for any length of time, it will just tend to get warm and this will shorten your battery life. If you do parallel two 70A alternators onto a 440Ah battery bank it wouldn't even demand more than one alternator could produce for more than a few minues, after this there would be no benefit. If you want to increase your charging capabilities then a high output low RPM alternator would help - however; The major benefit of most special alternators such as the Balmar is that they come with a far better regulator then the standard automotive alternator fitted to most narrow boat engines and this can probably be achieved fairly cheaply and easily by modifying your existing domestic alternator. I am guessing here but suspect you have an Isuzu engine and if this is the case then it probably has a variety of Lucas A127 alternator fitted and this can be fitted with the "tractor" regulator which should reduce your charging times significantly. A monitoring system of some description is an excellent idea, then you will actually know what is going on and be able to use your system to best effect. Have a look at the Smartguage or the Victron BMV-600S. Regards Arnot

I think you are probably right here it certainly looks like cell reversal given the rapid decline from 12.5ish to 10.5ish. Anyway, when I have finished cooking the last six batteries I am going to see if I can work out which cell(s) in each of them has departed this world. I suspect that there may be a pattern that emerges, what would your guess be? Would you be interested in the test data? Cor! Battery porn! It looks magnificent, you would cry if you saw my setup. You don't want a beta tester do you? Regards Arnot

True enough as stated but I didn’t mention the alternator loading. The problem I have noticed tends to occur when the batteries are almost charged and the regulator is having to work for it’s living. Under these conditions, at lower engine speeds and fast idle, the engine often wangs about like a demented zebedee. The result is that all the wiring, control cables and pipework to the engine take a battering and often the control wiring plug comes undone. No doubt with a Gardner that has a governor response that can be plotted on a calendar it would be a different story… Interesting (and scary)! I may well stand corrected here. I have seen this problem before but not in every case by any means. Do you think this reduction in capacity is permanent or may they recover with some nursing? I have four Mastervolt 270Ah AGM’s here under test and they have collapsed to about 20Ah on a C20 load. I also have four Elecsol 270Ah “carbon fibre” leisure’s with a similar problem at under a year old. Both have ample current output when charged but just won’t hold it. I also have twelve Squadron Energy 270Ah gel batteries that were installed in a 24V network for three years and discharge to 50% or lower six days a week for all this time. These mostly still have a reasonable capacity but won’t deliver even moderate currents (C20) without the voltage collapsing to the mid tens after about 20Ah but then they carry on for ages, some to as high as 230Ah. I am still testing these (12 x20 hours takes a while on a single channel logger!) because they were installed without balancing links and I wanted to see if there was any correlation between the battery condition and their place in the network. Regards Arnot

Congratulations Sven, I think that this first time a query of this type has had almost all the information necessary for a considered reply. It does my heart good to see it (and Gibbo’s pacemaker ) So, let’s do the obvious stuff first. The starter battery charging is fine, just don’t worry about it. You need so little power to start an engine (usually less than 0.2Ah) that a bicycle dynamo would put it back in in minutes. As an observation, it would be a good idea to check your fanbelt tensions. From the images there seems to be a bit of rubber dust around (although this may not be recent) and that is usually a sign of slipping belts. As a rule of thumb, if you can make the belt slip by turning the pulley with a spanner then the belt is too loose. This test should turn the engine. All the measurements you did are good and useful but it might help to check the voltage between the domestic alternator casing and the domestic battery negative. This will tell you how much you are losing through the negative path. Any more than about 0.2 volts at full output could be improved on. The domestic altenator is an Iskra and generally they are pretty good. The one you have should be able to just about reach 120A with perfect wiring but most will do 90A. Another plus is that they are geared to give quite a high output at reasonbly low revs. The ones I have tested don’t seem to give amy more after 1300 rpm. It would be well worth while adding a new cable from the domestic alternator output to the domestic battery directly avoiding the existing engine wiring. I would suggest 25mm csa cable the slight benefits from using large cable tend to be negated by not being able to terminate it with the correct stud diameter. This should reduce the voltage drop from the alternator to the batteries you have measured but do check this when the job is done. I don’t actually agree with Gibbo about the gearing, my experience is that if they are geared up further then it tends to make the idling unstable as the alternator regulator hysterysis beats with the mechanical diesel pump governor and I think that the benefit would be disproportionate to the cost. Your batteries are probably still OK but it is true to say that totally flattening them will reduce their service life a bit. It’s a bit of a generalisation but batteries tend to have a limit to the power they can store and release in their life so the deeper you discharge them the fewer cycles you get. With a fairly standard leisure battery, discharging to 80% down regularly on a daily basis would probably translate to a battery life of about a year, perhaps slightly less. You already know that it is a rule of thumb to have a battery that will support the nomal daily usage without discharging more than 50%. Smaller than this tends to lead to premature failure, larger than this tends to batteries dying from old age before they are worn out. My experience is that liveaboards with your sort of usage tend to need four to six leisure batteries. I would suggest you invest in monitoring PDQ and given your obvious grasp of the nature of the problem and ability to interpret hard data results, despite the ease and simplicity of the Smartguage, I would suggest the Victron BMV-600S. It shows amps and volts, consumed energy in Ah and calculates from a theoretical capacity ceiling the time to go. It also stores some historical data and if you want to get really hi-tech, you can plug a laptop in an datalog the readings into Excel. I do a lot of government work and always specify this monitor because I can get some idea of what has gone wrong. Some of the current drain figures you quote have been based on assumptions about the battery capacity and may not be correct, a BMV-600S would give you hard facts. One of the major benefits of these is that you can easily see what minimum speed you need to run your engine at to maintain maximum charging and also when you can turn it off again. If you want to charge your battery from a generator or shoreline occasionally then you really need a decent sized charger (50A plus) and these are expensive for a goodun. Given that you have a chinese inverter at the moment (and I don’t believe the 5kw for one moment) it might be a wise move to invest in a Mastervolt or Victron pure sine combi. It will give you a good charger, a good inverter and a low quiescent current draw. As well as this the automatic switching will keep the mains wiring simple. Now the batteries. As an alternative to merely adding a couple of leisure battereis, given that you have just bought the boat and use it to live and work on it would be worth considering a big investment in this area if you can afford it. Leisure batteries are cheap and cheeful and provide a solution to the power storage problem of sorts. However, if you not only rely on your power system for living and earning but use it heavily (as you do) then 2v storage cells would be a better and cheaper solution in the longer term. A 600Ah bank installed would probably set you back about £2K but you would be able to use the top 80% safely so this equates to a 1000Ah leisure bank. In addition, it would last ten to fifteen years and the low impedance would allow you to top up the power far more quickly thus saving fuel. One of my customers reports a saving of 40% plus on fuel costs! Especially if you intend to invest in storage cells now or in the medium future, an external regulator for your domestic alternator would be a good investement but it doesn’t need to be a whizzy multi stage digital doohdah with lots of LED’s. A simple external regulator that can be set to the voltage appropriate the the battery bank you have will do just fine. In addition with a larger battery, a Smartbank to parallel the alternators would bring down charging times. Hope this helps… Regards Arnot

This idea works well on vehicles as well but it takes more than an hour or two to wire up and set up. There's also the small matter of the second mortgage... Still it's quite impressive when you see it in the flesh. Regards Arnot It's not really technically feasible to run a synchronous mains alternator from a narrow boat engine, if you gear it so that the voltage and frequency are correct at a reasonable engine speed, when you rev the engine the alternator disintegrates to the point where a lot of the innards would go through a seive. Seen it done! The Travelpower/Electrolux system works but is expensive. I think the best way on a new boat is a combination of proper battery, big alternator and good high power inverter. Regards Arnot

What I do in new boats is to fit a 2v cell battery and a high power alternator (or use the 180A one that comes with a Beta as an option)along with a Mastervolt 2500w combi. It's simple to operate, effectve, long lasting and reliable but is is expensive. At this stage you don't need the engine running and the power you use can quickly be replenished in a couple of hours cruising. Petrol gennies on boats? Personal opinion - having had to rescue someone incinerated in a petrol fume fire, I wouldn't have petrol or LPG any where in my boat apart from in very small and very carefully used and stored quantities. A viking send off is all very well but it's best to be dead first. Regards Arnot

They are still available but quite expensive and retro fitting one to an Isuzu would not be a simple job. Then there is the reconfiguration and/or modification of the mains wiring system to do as well. Also the latest travelpower systems don't seem to be as reliable as the older one, I have had to repair three of them now and apart from one that was under warranty the costs were quite high. The usual reason for having one is to be able to run a washing machine and other occasional high load mains electrical devices and for this the Travelpower works well - however... It might be worth thinking of doing what I do on new build boats now. The newer, inverter charger combi's from Victron and particularly Mastervolt will run a washing machine, tumble dryer, microwave etc perfectly well (but not all at the same time) and with the addition of a high output capacity and decent battery bank the need for the Travelpower is diminishing. Either way it's not a cheap round! Regards Arnot

Don't assume that becuase an alternator is capable of producing 80 amps that it will... Even if the engine is turning it fast enough it is unlikely that two leisure batteries would accept 80 amps safely for more than a few minutes. It is more likely that the major problem is in the wiring and alternator control if your engine is a standard installation. It can allow you to charge your batteries more quickly if the alternators are both connected for charging the domestic batteries but not until the wiring and regualation are optimised and then only really on larger battery banks. It might be an idea to have a professional have a look at it and give you a bit of advice before you do out and spend money on spec. As for more batteries, in my experience a liveaboard tends to need between four and six 110Ah leisure batteries. Sterling battery chargers are cheap but you do tend to get what you pay for in this area. Mastervolt and Victron are a far better and more permanent fix but come at a cost. Regards Arnot

I use genuine turpentine. It seems to work well and smells lovely! Regards Arnot

On a nine year old alternator you are probably better not messing with the brushes and slip rings, they both wear a bit but my the time they are beyond use, ther bearings are well on their way and the stator insulation is starting to break down. All of which spells new alternator time but not until the red light comes on, it makes horrible grinding noises or the smoke escapes. Just don't only change the brushes - you never manage to get them to run in the slip ring grooves the originals sat in and shortly after what seems like a succesful repair, unless you are lucky, the detritus caused by the bedding in of the new brushes and sometimes the copper wool machined off the slip rings by them starts to short circuit and it all goes into Chernobyl mode. Re the measurements, these are very useful but where were the positive and negative measurement points? i.e. was the positive probe of the meter connected to the output stud of the alternator or the positive terminal of the domestic batteries or somewhere else? Was the negative probe of the meters connected to the domestic battery negative, the main earth terminal, the engine block, the alternator case or somewhere else? Generally the Iskra alternators produce a reasonable output even at fairly low speeds but it is fair to say that the pulleys on the later engines have got a better belt system and higher gearing. My suspicion is that if you get the wiring and control systems well sorted you probably won't need to mess with the pulleys, if you do then it's best to get them from Beta, they do sell them as parts. You need to be a bit careful using a clamp ammeter to measure alternator output. If you get it near the alternator, the stray magnetic fields tend to give false readings. You need to check the tacho accuracy with an optical tacho. This may be a red herring but often both the domestic and starter alternators have the necessary output for a tacho and if it has been plugged into the wrong one it will give incorrect readings. Regards Arnot

Assuming that the alternator you have is one of the common vehicle derived units such as the ubiquitous Lucas A127 the answer is that the regulator does not actually measure the output of the alternator. It is internally connected to three auxiliary diodes that provide the excitation supply for the rotor. This internal supply is not subject to the load that the batteries (and any other power usage) draw which comes through the positive side of the main rectifier. As the output of the alternator increases, the voltage drop on the main rectifier increases but the voltage drop on the auxiliary diodes doesn't. Because it isn't connected to the output, the regulator does not know this has happened and therefore cannont correct for it. Hence the voltage on the output sags by this difference. So; the pheonomenon you correctly observe whereby the higher the load the lower the ouput voltage is entirely normal on a vehicle type alternator. In this type of machine the regulator's job is not maintain the voltage output of the alternator precisely but to balance the load presented to the battery and prevent it discharging. The big difference in terms of operation is that in a car, the power is almost always used whilst the alternator is generating it's output and very little is required to replenish that used from the battery to start the engine (typically about 0.1Ah). In a narrow boat, conversely, while the engine is running and the alternator is generating output almost none is used at the time, it is all stored in the batteries for use later. Installing a battery sensed regulator circumvents this problem (and a few more) by having a lead that does actually allow the regulator to "see" the alternator output. In fact, it is even better than this, it allows the regulator to "see" the input to the battery and maintain the voltage at this point. Essentially this is the difference between an alternator intended for the supply of vehicle loads such as headlamps and heaters etc. and the sort of alternator ideal for narrow boat useage when it is essentially used as a rotary battery charger. Hope this helps, Regards Arnot

Reading between the lines here and accepting the risk I may be off the mark, would I be correct in assuming that you want to improve your battery charging in terms of how well they charge and/or how quickly they charge? If so then a more economical and probably more effective way may be to keep your original alternator and merely to improve the regulation system. A lot of the Isuzu's are fitted with a form of the Lucas A127 alternator and these can be modified quite easily to charge the batteries far better than the standard one will. Regards Arnot Have you tried replacing the alternator output lead that goes to the stud on the engine mount and thence to the batteries with a far thicker one directly from the alternator to the batteries? This is a common limiting factor on Beta engines. It's worth checking the volt drop on the negative as well, the standard wiring is OK but there is a tendency for the conection stud near the starter to go high resistance. Regards Arnot

I would say no and no... but it's a bit 50/50 The benefit would probably be marginal and the extra terminals on the alternator would be likely to compromise long term reliability. However, if you have access to a test meter it's easy to check the voltage drop which should really be the decider. Regards Arnot

Your inverter charger will consume about 1 amp when idling. When cruising there is not much benefit in turning it off. When moored up and not on a shoreline it would be better to turn it off if you anticipate not using any mains for a whle such as overnight but it's not a major deal. Some inverters have a facility to automatically turn on occasionally for a while to dry them out even when on battery power and if yours has this then it is a good idea to use it if the boat is t be left for more than a day or two. When moored up and on a shoreline, in the summer it is better to turn it off. this will extend the life of the storage capacitiors. In the winter, it's best to leave it on so that the minor current draw prevents the build up of condensation on the circuitry. HTH Arnot

It does sound like alternator failure (probably worn brushes) but I would be best to get it checked out by a boat electrician before rushing ut to buy one. Regards Arnot

For what little it will cost, it would definitely be worth it. It's not just the shortening of the cable but taking out redundant terminals as well. This is pretty much the first thing I do when improving the charging on any Beta setup. Regards Arnot

I have to say that if it isn't bothered with it probably wouldn't matter too much. The risk is negligible. If the casing was mounted to the steelwork of the hull then this would do it anyway. If it is mounted to a non conductive surface, the earth does two things; it provides a protective earth for anyone working on the inverter when it is disconnected from the distribution should they need to do so or if the consumer unit develops an earth fault and it provides part of the interference supppression system. For what it costs and the time it takes, you may as well just do it. Arnot

It probably would but... Wouldn't it just be lovely if regulations were drafted in a way that made their intent and detail transparent! So; From Section 3(1)(a) of the Communications (Television Licensing) Regulations 2004 A licence (TV licence (including colour) General Form) - [should be obtained] a - to install and use television receivers at the single place specified in the licence or, as the case may be, in the single vehicle, vessel or caravan so specified ("the specified location"); b - to install and use television receivers in any vehicle, vessel or caravan being used or occupied by the licensee or by a person normally living with the licensee at the specified location, being installation or use not covered by a licence described in Schedule 5, provided that a receiver may not be used in a caravan, other than a touring caravan, at the same time as a receiver is being used at the specified location; and c - for the use anywhere of any television receiver powered solely by its own internal batteries by the licensee or by a person normally living with the licensee at the specified location. It is difficult to see how "specified location" could reasonably be stretched to include anywhere at any given time as would be the case for a CC'er. Sub section "a" refers to "install" without any defintion of the term in context Sub section "a" refers to a "vessel" without any defintion of the term in context Sub sections "b" and "c" refer to a "licensee" without any defintion of the term in context If sub section "c" were to be taken at face value, everyone with a laptop or mobile phone with internet access would have to carry a licence. So, do we interpret this to mean that if we own any piece of equipment that could possibly be used to watch television anywhere or in any way we have to have a license regardless of intent to actually do this? Or do we take the regulation at face value and assume that because the television is not "install"ed, it is exempt and that because of this we are not "licensee"s and are thus exempt from sections "b" and "c"? It is a can of worms isn't it? Regards Arnot PS if you really want to read it, try this!

Either something like that or just use a simple meter or even... just do without any monitoring! Realistically, if your bow thruster battery goes flat you won't die and the fact that it doesn't work will alert you to the possibility that there is a problem. There is always the 15' Ash manual version. In this age of I-Pads there is a tendency for people to introduce layers of complexity and sophistication into narrw boats almost for it's own sake. As the colonials say "It's hard to remember when you are up to your arse in alligators that the prime objective was to drain the swamp". Surely one of the reasons for getting a narrow boat is to simplify life and slow it down? Keep it simple I say... Technology that does something that actually makes your life easier can be OK but technology that merely gives you more to worry about is questionable. I have forgotten who said it but the trouble with control freaks is that when they lose control all you are left with is the freak Enough of the philosophising, I'm off to fix a travelpower control unit that didin't like welding. Regards Arnot

Given that the inverter is just that and not a combi, then the earth stud on the casing should be connected to the main hull earth point. This is the single point where the DC systems are also bonded to the hull. The cable size should idealy be one up (4mm) on the power conductor side (2.5mm). Your consumer unit probably has all the earth connected together internally, probably to a series of linked connections but this can easily be checked with a meter. All the earths on the outgoing cables should be connected to this. There should also be a 4mm bond between the consumer unit and the main hull earth point. The shared neutrals on the outputs, whilst not ideal, is quite common and providing the whole installation is protected by an RCD (which it certainly should) it is going to be safe in this respect. Consumer units with two outputs are designed with the anticipation of a ring main for the power outlets connected to the 16A outlet and an immersion heater connected to the 6A outlet. You may well find that it is difficult to connect more than two radials (plus the immersion heater feed) to this type of unit. It doesn't make it clear in the installation or user instructions for this unit if the neutral output is connected to the protective earth internally although in some of the installation diagrams on the Victron website metion this. The neutral should be bonded to the protective earth at the output of the inverter if it isn't done internally. Regards Arnot

Whilst this would certainly work, it may not be necessary to go to that level of complexity and expense especially in this case. An additonal downside of this method is that the inverter would have to be active almost all the time whilst cruising for no other purpose. Given that the boat in question will have a canbus distribution system, there is no reason why the largish power cables that will have to run almost the length of the boat anyway could not be also used to charge the bow thruster battery. Remeber that for how little this will be used it really doesn't matter if it takes a while to recharge it completely from flat. There is a slight issue about battery isolation but this can be sorted with an electrically operated isolator triggered by the domestic alternator warning light. This means that it automatically isolates when the engine is off. Regards Arnot

I may just be totally wrong here but seem to remember looking into this topic many years ago when I used to sell car audio and it became possible to receive TV in your car. I don't remember where it came from but at the time there was an exemption for battery powered TV sets... Discuss? Regards Arnot

You just have to accept that some people are soon parted from their money Arnot