Graham.m

The manual is available at https://www.victronenergy.com/upload/documents/Manual%20-%20MultiPlus%203k%20230V%20Ve.Bus%20enabled%20-%20rev%2000%20-%20EN%20NL.pdf If you look at page 24 the DIP switch settings for the assist current are there do read the manual Procedure The AC input current limit can be set using DIP switches ds8, ds7 and ds6 (default setting: 30A, automatically limited to 16A in 16A models). Procedure: set the DIP switches to the required value: ds8 ds7 ds6 off off off = 4A (0,9kVA at 230V) off off on = 6A (1,4kVA at 230V) off on off = 10A (2.3kVA at 230V) off on on = 12A (2.8kVA at 230V) on off off = 16A (3.7kVA at 230V) on off on = 20A (4.6kVA at 230V) on on off = 25A (5,7kVA at 230V) on on on = 30A (6.9kVA at 230V) Remark: Manufacturer-specified continuous power ratings for small generators are sometimes inclined to be rather optimistic. In that case, the current limit should be set to a much lower value than would otherwise be required on the basis of manufacturer-specified data.

Manual here which should help you http://images.mastervolt.nl/files/50261131W3_5User091224EN.pdf

Did your remote panel look like http://www.advanceyacht.co.uk/paguro-parts-store/remote-control-panel-with-15m-cable At one stage I have a suspicion the MasterVolt whisper was a badge Paguro

Geoff, Perhaps this will be nearer the the original http://www.diy.com/departments/rooftrade-black-universal-bitumen-paint-5l/566181_BQ.prd

OP posted 60 fest there and back

Wasn't going to bother, but whatever way you look at the two graphs the alternator is power limiting. Hence on the first graph as the battery voltage came up the current goes down. On this graph the current level drain is greater than can be sustained so the voltage level drops. Also regarding the comment about higher charge rate when you restarted the charge on shoreline. Think about surface charge and the voltage tension across the plate forcing the reaction deep into the plates so that it can revert lead sulphate back to lead & lead dioxide. Also the opposite effect when the available surface charge has been used and the time taken for the charge to dissipate from the plate core to the surface to rebalance the voltage tension across the plate.

Surely if you actually know things why is it irritating when others say what they know. Surely you need to have faith in what you believe is right.

Yes

Putting it simply you did not know that the smartgauge was out of spec or right on the edge of spec when you got it, your means of checking was not calibrated to the standard needed to check it. Thus by adjusting it using an un-calibrated DVM as the reference you do not know what voltage the smartgauge is set to. Your batteries are two years old, you do not know the actual capacity of the batteries, they were nominally 450Ah, and what are they today. Unless you specifically do a discharge test, any figure you give them is a guess. I would hope they are up in the 400s. The Mastershunt displays calculated Ahs, and then using the battery capacity you have entered gives a SoC. Now as the battery capacity is not really known, and is it only a guessed battery capacity given by you to the Mastershunt, the Mastershunt is only working on guessed capacity that you gave it. Hence, the more accurate of the two figures is Ahs. The voltage spec for the smartgauge is 0.5% of the reading. Thus at 12.7V the error can be +/-0.0635V. If the smartgauge were as self-correcting as you seem to believe it would not matter what the voltage it was set at. However, as we are both aware it is important that it is set so the voltage reading is within 0.5% of the reading otherwise it reads inaccurately. BTW, if you check a gauge that is supposed to have an accuracy of 0.5% against a voltage source that only has the same accuracy of 0.5% you cannot tweak the gauge into the centre of its band. If the source has an accuracy of 0.005% then the source more accurate than the gauge and you can tweak the gauge to the centre of its accuracy band. I get the impression that you have not done much calibration adjusting. As for having a debate I am not having a debate, because the inaccuracies in the instrumentation you are using there is nothing to debate, the inaccuracies make the readings unreliable. You have my opinion

“There is no need to quote AHs used when I have given the MS % SoC and the battery capacity set into it. Thus 75% SoC would be 112.5AH taken out etc.” Sorry that is a load of rot. You are arguing that the Mastershunt’s SoC is inaccurate. Thus, you cannot just quote its SoC and do a simple conversion to Ahs using two unknowns, i.e. the capacities of the batteries used twice and the SoC of the Mastershunt. At least quoting the Ahs used does away with an unknown, unmeasured battery capacity. “5 minutes is a short resting time but we can consider that the reading will be no higher than would have been had the batteries been left for say 1 hr or more, and probably a bit lower (but perhaps not very much, it will depend on the load history up to that point).” That is interesting it does make me wonder why the battery industry knows less than you do and why arising from years of professionally making batteries and testing them do they stupidly come up with the 24 hour resting period. Sorry that is nonsense. “I suspect they were all calibrated at manufacture, none of them were "certified". However I am not attempting to suggest that this is a rigorous scientific test.” I am sorry you are trying to sell the idea that the Smartgauge is better than the Mastershunt. Therefore, the test must be rigorous, accurate, and not inaccurately done. Therefore, you calibrated the Smartgauge to an unknown voltage, and thus the tracking of the smartgauge to your DVM etc is not surprising. Therefore, I would suggest that the accuracy of your Smartgauge is totally unknown. Bearing in mind that the smartgauge relies totally on being able to accurately measure the voltage for its algorithms to be able to accurately calculate its values, if it is not correctly calibrated its readings mean nothing. I wonder why you did that, was it another smartgauge that came out of the factory incorrectly calibrated. I think the manufacturer will tell you that the basic set-up of its voltage calibration is very important to its overall accuracy. Therefore, I am afraid that until your smartgauge is recalibrated, using a voltage source that is accurate to better that 0.0005V, any comparison that you do will be irrelevant. It would also explain the difference between the Mastershunt and the Smartgauge. I would also suggest you need to get yourself a properly certified calibrated DVM accurate to better than 0.005V over the voltage range used for the tests and if you are going to continue doing this sort of test and publishing the results keep its calibration valid. “For me the point was that after a partial cycle the MS was quite a way out, the SG was a little out…” You do not know this, as the Smartgauge is not correctly calibrated. It has a mythical calibration you gave it using an un-calibrated uncertified meter as the reference. "The key point is that the error in the Smartgauge we saw was the full extent of the error since all the time it is discharging, it has something to go on." Sorry that is not correct if its voltage calibration is not correctly calibrated, it is a total unknown. In my opinion you have been playing at pseudo-science to prove what you want others to believe which I find a great shame.

nicknorman, on 24 Jan 2016 - 8:33 PM, said: I'm doing a monitored comparison discharge between the Smartgauge and the Mastershunt tonight, and was going to post the results on my "smartgauge accuracy" thread but I though I would add a bit about the Mastershunt since it seems to be a relatively rare beast, and this thread about battery monitoring seemed the more relevant one, so I'm going to put it all here. We started today with around 85% Soc, cruised for a good few hours and tied up with both the Smartgauge (SG) and the Mastershunt (MS) showing 100%. The tail current for our 450AH bank of T105s was 3.7A = 0.8% of capacity at 14.8v, battery temperature 21C. The batteries are 2 years old and the MS tells me that the total charge taken out is the equivalent of 40 full cycles down to 0%SoC ie 40*450 = 18kAH. As far as I can tell they have the original capacity, in fact better than original since they need 50-100 partial cycles to fully "bed in". The MS tells me that the average discharge is 121AH ie down to 73% SoC. That would imply around 149 partial cycles (ie 149 days out of the marina) which is probably about right. Charge Efficiency Factor (ie proportion of charge put in, that can be taken out again, or if you like the reciprocal of the extra charge needed to be put in to replace charge taken out) is calculated by the MS and currently showing 95% The Smartgauge is configured thus: Battery type: 1 That's it. The Mastershunt is configured thus: Battery capacity: 450AH Battery type: Wet Nominal voltage: 12 Amps = full: 1.5% (ie the tail current when the counter will reset to 100%) Float voltage: 13.24v (voltage must be above this for the counter to reset to 100%) Absoption voltage: 14.4v (not sure what this is for) The mastershunt is a shunt + 500A fuse that does all the stuff mentioned above but doesn't have a display. You can connect it to a PC (inconvenient) or a Masterview Easy (ME) touchscreen display, which is what I have, by means of the Masterbus data network. Data is sent from the MS to the ME in digital form, ie all the processing is done in the MS itself. The ME is "plug and play" with other Mastervolt products including our Mastervolt Combi 12/2500-100. When you plug the Combi and the MS into the ME they are both detected and the display looks like this: Masterview devices.jpg You can press on any of the 3 items to configure them to your heart's content, eg changing the Combi's charge voltage and max current to whatever you like. You can also see all the parameters output by the devices, eg SoC from the MS and loads more. The MV has a "favourites" page which you can configure, taking data from any connected devices and merging it onto one page. Max 6 items. Mine is set up like this: Masterview Favourites.jpg Top row, SoC, Battery voltage from the MS Middle row, Current flowing into or out of the Battery, Battery temperature from the MS Bottom row, current going into or out of the Combi, Inverter output (or throughput) current (ie at 230v) Later (tomorrow) I'll post the results of the comparison discharge between MS and SG. Oh and just to mention, I need to put my glasses on to read the ME. I don't need to put my glasses on to read the SG. nicknorman, on 25 Jan 2016 - 7:22 PM, said: So of course one is then stuck with the figures at the end of the discharge, to start the charge process. The Smartgauge was clearly significantly under-reading the SoC at this point. On this graph, note that the current axis is on the right ie it started at around 165A before rapidly falling off. I couldn't quite decide whether to continue the charge until fully charged or not. If I had have done so, I think you can see by the shape of the graphs that the two figures were converging but since the starting point for the SG was bad this didn't seem particularly useful. I therefore decided to terminate the charge prematurely in order to demonstrate one of the SGs major advantages which is that when it does go wrong, it self corrects without any user intervention. More of that in the next post. Recharge.JPG I think one of the things this exercise has demonstrated to me is just how complex battery chemistry is. It is easy to think of a simple model but the reality is complicated. For example, when I started to recharge the current was 165A, rapidly fell off to 125A, but then for some strange reason increased back to 130A. What is going on! nicknorman, on 25 Jan 2016 - 7:32 PM, said: What was interesting was the jump the SG took when I bunged on 200A of discharge current for the 2kw kettle and then 100A for the toaster, much more than the drop in the MS, and this was where it went from over-estimate to under-estimate. If you note the point about the final rested voltage, I think it shows that the MS was pretty correct, the SG was under-estimating. nicknorman, on 25 Jan 2016 - 7:37 PM, said: Well when the charging finished I had 84 on SG and 93 on MS. Just over 2 hrs later I now have 84 on the SG and 85 on the MS. So it is doing exactly what Gibbo said, it is holding its reading on discharge until the actual SoC passes the indicated SoC when it will become synchronised and track down - hopefully! I'll wait a bit longer and then do another graph. nicknorman, on 25 Jan 2016 - 10:31 PM, said: Well its all getting a bit weird now. I stopped charging at 90% on the MS and 84% on the SG. 4 hours later the MS is on 77% and accordingly I have taken out 13AH. The SG, however, is still on 84%. Which one is right? I switched everything off (missed the news on telly!) and quickly the voltage recovered to 12.65 on the Smartgauge, on my DVM and on the Combi's voltage measurement. To 12.56 according to the Mastershunt. So according to the Voc from the MS and Trojan's table of voltage vs SoC, the SoC is 83%. According to the other devices the SoC is 94%. And yet I've taken out 13% capacity (aka 58AH). As I said, what is going on? Anyway at the moment I believe the SG more than I believe the MS - which has obviously suffered from a cycle without reaching 100%. So, which reading is correct? Were any of the readings by a calibrated valid certified device? I suspect not. If not any or all of them could incorrect. The Smartgauge only reads 3 ½ digits so 12.65V could easily be 12.6V or 12.7V. As for the Mastershunt, Voltage accuracy ± 0.6 % ± 1 digit and State of charge accuracy: ± 1% whereas the Smartgauge State of Charge is ± 5%, Voltage Accuracy ± 0.5% So looking at the voltages taking into account accuracy: Which are being put forward as rested battery open circuit voltages after a relatively short rest. The battery industry recommendation being 24 hours. The longer the rested the higher the voltage. The smartgauge voltage assuming a correctly calibrated box could be 12.71V The Mastershunt assuming a correctly calibrated box could easily be 12.63V A difference of 0.08V Looking at State of Charge taking into account accuracy: Smartgauge SoC could be 79.8% but it has not changed since the end of the charge, possibly, it has not re-synced Mastershunt SoC could be 78% A difference of 1.8% Interestingly the Mastershunt at the end of the charge showed 93% (was this the value at the same time that the smartgauge showed 84% immediately or as the charging was stopped) and at this point 4 hours later, the Mastershunt showed 77%, which is 16%, used and the Smartgauge 84% nil used. Ahs used is declared as being 13Ah, (I am assuming this is a reading from the Mastershunt and not a calculated figure) as a percentage of the declared available battery capacity 90% (at end of charge) of 450Ahs, 13Ahs is (13Ahs/405Ah =) 3.11%. Now is the Mastergauge incorrectly set or is the battery capacity less than originally declared, say down at well that would be 100Ahs. If we use a later figure give for Ahs used, 58Ahs how does that affect the figures. Mastershunt at the end of the charge showed 93% (was this the value at the same time that the smartgauge showed 84% immediately or as the charging was stopped) and at this point 4 hours later, the Mastershunt showed 77%, which is 16%, used and the Smartgauge 84%, nil used. Ahs used is declared as being 58Ah. As a percentage of the declared available battery capacity 93% (at end of charge) of 450Ahs, 58Ahs is (58Ahs/418.2Ah =) 13.86%. Now that would make the Mastershunt to be within 2.14% of the expected reading. Is the battery capacity less than originally declared, say down at 418.47Ahs. Basically this tells us that either of the boxes could be right and does not show either box to be correct or incorrect, the differences are too close to decide. If the charge level had been taken back to the starting level i.e. to “The tail current for our 450AH bank of T105s was 3.7A = 0.8% of capacity at 14.8v” or the battery SoC been check by the Hydrometer that the owner has; we might have got something out of this information. Instead of something where apparently the tests were biased towards the smartgauge. nicknorman, on 26 Jan 2016 - 12:02 AM, said: HIGNFY was a repeat! Anyway by 23:30 the SG was on 81%, the MS on 72%. Switching everything off for 5 mins gave 12.55v on the DVM, 12.57 on the Combi, 12.58 or so on the SG, 12.47 on the MS. Even taking the lowest of these gives an SoC of 77%, taking a mean of the values gives over 80% and either of these puts the SG nearer than the MS. The latter is clearly going out of sync after just one cycle of failing to reach 100%. So in some ways this has become a victory for the SG since its errors are not cumulative. It may bounce around the correct SoC a bit but it never departs too far unlike the MS whose errors are boundless given enough cycles. But then again what is SoC? From the results tonight I am more convinced than ever that it is very hard to define or measure by any means. Graph of post-charging SoC showing the SG biding its time until the actual SoC passes the indicated SoC. Discharge2.JPG Now what does this tell us I note that this time there are no Ahs used readings. The voltages were taken after 5 minutes resting and I would suggest are inaccurate because the battery is still settling and tell us nothing. Again, which of the instruments were calibrated and certified? What were the State of Charge readings when the voltages were taken? The Smartgauge has an accuracy of +/-5% and that means that the 81% read could be 76.95% and is still re-syncing. The Mastergauge has an accuracy of +/-1% and that means the 72% reading could be 72.72% Voltage wise the Mastergauge could be 12.395V or 12.54V Voltage wise the Smartgauge is only readable to 3½ digits so 12.58V must be a guess as it flicks up and down, it was either 12.55 or 12.6V could be 12.49V or 12.66V Whichever way you look at it the voltage readings are both within spec Which is right I do not know, the voltage readings because of the shortness of the resting period tell us little or nothing. I do think these two gauges are very close. I think readings done the next morning when the smartgauge had had a chance to fully re-sync together with specific gravity readings from the batteries would have shown results that were a lot more accurate and interesting. Taking the same voltage reading with four different readings with four different meters does not mean that any of the readings is correct. Just that you have four different meters that read the voltage differently. Think someone quoted a Chinese Proverb something like, “the more meters the more confusion”, and that is so true.

Don't think you read my post fully. I said boater told to start charging at voltage X and stop at tail current Y. Both those facilities are easily available on an Ah gauge. The smartgauge does not tell the boater when to stop charging and I understand that the designer suggested other ways to determine the end of charge.

I have not the foggiest and did not enquire. I do know the boater is unlikely to have installed the gauge themselves. I have a niggle it was installed when other electrical work was done on the boat, but can't be sure where he got it from, but he had firmly got it and was carrying it out. Hopefully I have changed his mind.

I think in the boat/gas locker situation one has got to asked how did the gas bottle get to be alight. I am sitting here trying to work out a way a gas bottle leak in a gas locker could get light and can only think of one. The gas bottle has leaked gas and as it drained out of the locker drain a spark occurred externally light the external gas and flashed back into the locker. I believe that remote chance would result in an explosion any way. Thus it would be run time. Can you think of another scenario, excluding smoking etc over the gas bottle?

I have a niggle that a gas bottle when heated to a certain temperature will explode and the out rush of gas ignite. Surely this is what the fire service is worried about when it leave a hose playing on gas bottles.

In theory you can do what you want 500W out of a 80Ah battery. By doing so you are going to take the battery down to below 50% of its capacity. If you do that there is a distinct possibility that you will damage the battery. Gels don't like being discharged to or below 50% of capacity. So that leaves two options 1. Increase the size of your battery bank and at the same time increase your ability to charge those batteries. Maybe to 150/200Ahs of batteries. 2. Use a portable pure sine wave generator. Depending on what it is a 1kW generator should be OK. What is it you are going to need to be using?

I think perhaps the advocates of the smartgauge need to think about what they say, for example that it will tell people how long they should charge there batteries for. In the recent experiment reported on here two gauges were tested, unfortunately without a master reference. In that test, stopped when the smartgauge reached 100% with a tail current of 12/13 amps. The other gauge the MS was reading 94% SoC, now with a tail current of 4 amps or less in this case I might have agreed the batteries were at 100%. However, with a tail current of 12/13 amps I believe the MS at 94% was nearer perfect on the mark. But neither is the perfect answer. I have just returned from a boat with charging problems. They had been told to charge to 90% on their smartgauge. Now as when charging the smartgauge has an accuracy of +/-10% that 90% could have actually been 81% or 99% or something in between. No matter which the batteries are being under charge, thus allowing a buildup of sulphate. So the battery is charged to 90%, the sulphate hardens and the smartgauge learns the new capacity (90% of the original). Then charged to 90% (81% of original) and more sulphate is laid down and hardens the sgauge learns that capacity. The it is charged to 90% of the 81% of original capacity to 73% of the original capacity and so on and quite rapidly there is a sulphated battery. Now it does not matter at what percentage of SoC you start unless the batteries are fully charged sulphation will start and grow and that to me is a major problem with the smartgauge. The Ah meter type have at least the ability to read tail current and voltsge accurately and tell you when that current has ceased to drop and the battery is fully charged. I am coming the the conclusion that people should be told to charge their batteries at voltage X and to charge the until the tail current is down to 1% of capacity. This is a job an Ah meter can do with accuracy. To buy separate meter with the level of accuracy needed from my research will cost more than Ahgauge.

There is nothing that will easily read the state of charge while charging. Except something that reads current (amps) into the battery and thus make the tail current available and allow charging down to 1% tail current of capacity. At least by doing that there is a reasonable chance of a full charge. The smartgauge even in the recent test published on here did not get to that level before reaching 100%. Whilst the MS gauge being tested along side it got to 94% SoC. From the tail current declared in the test I believe the MS gauge was almost spot on. I have just come from a boat with a smartgauge. The owner relies totally on the gauge and has been told he only needs to charge to 90% on the gauge. Now the gauge has an accuracy while charging of 10% so he could be charging to 81% or 99% or something in between. But let's say it is 90% that means all the sulphate is not removed and that will harden and the smartgauge takes the batteries to only have 90% of their actual capacity. The result is the 90% charge becomes 90% of 90% (81% of capacity) and the sulphating increases. So it goes on and battery life is shorten because of sulphating caused by bad charging regimes. I am not sure but am starting to believe it would be better for the batteries and the overall costings if users were told to recharge at an on load of voltage X and to charge until a tail current of say 1% of capacity is reached.

Don't think that is correct everyone I have seen has been aboard a liveaboard. As it happens I am going to look at another one tomorrow, with charging problems, yep a liveaboard.

There a are colreg compliant magnetic nav light, good for up to 15 metres. Mine are on the boat so can't give details. Mine go onto of the steel front door hatch. For the stern light I use a magnetism steaming light mounted on the top of the stern locker.

Surely that depends on manufacturer, Trojan it would be 80F or 27C as well as most US companies

lol Forgot about Peartree, yes they found me a mooring overnight so I could recharge an electric boat I was moving several years ago. Doh

That wouldn't be a problem here, but they seem to have enough maintenance moorings.

Not nice,

Think you will find most marina moorings cannot be lent. Several marinas I know reserve the right to use the mooring if the boat is not there. Never known one to do so though.