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do you want to talk about isolation Transformers and how they compare well that's the best isolation Transformer is that it does the same job much more efficiently and much more reliably and because there are ways even when a galvanic isolator is is working properly where it can be essentially overcome um and then you get galvanic currents coming through that line the the isolation Transformer is basically uh pretty much Bulletproof it breaks that circuit to show and then it effectively it creates a new AC circuit on the boat so then if you get any fault currents on the boat the path for the fault current is always back to the source of power and since the source of power on the boat is the isolation Transformer it's going to go back to the isolation Transformer and it's not going to go into water or go anywhere else it's basically going to be contained within the bone so it gets rid of the galvanic corrosion issues and it creates a much safer environment on the bone but of course they're fairly expensive and some of them are pretty heavy and they can be noisy some of the older ones um so there's always some downsides to these Technologies yeah you know what we've done for years or now bro um all modern well most modern marine battery chargers will accept uh a universal import just like you can go anywhere in the world and you can plug in your cell phone charger or your laptop charger well the most modern battery chargers are the same you can plug them in anywhere in the world so if you take all of your AC loads and you put them on an inverter or if you've got high loads stacked inverters two or three inverters and you run the entire boats AC loads off the inverters and then you have one of these Universal um battery chargers you can go anywhere in the world plug in the battery charger will feed through the batteries to the inverter and run your AC stuff if the AC loads exceed what the battery charger can feed from Shore they just suck off the batteries and discharge the batteries a little bit and then when the AC loads go down the battery charger will recharge the batteries they'll catch up so effectively you micro cycle the batteries and you run all of the onboard AC equipment off the inverters and you have no no no hardwired connection between short power and the boat's AC circuits because you're going to the battery charger from the battery charger to the batteries from the battery to the inverter and from the inverters to the boat AC systems and you can run nowadays and you can stack inverters to get maybe 20 kilowatts and you can run a ton of um of air conditioning for example and then if you don't mind rambling on for a moment if let's say we have a whole bunch of air conditioning on the boat and over the course of the day the total load is 72 kilowatt hours so that's over 24 hours if we divide the 72 kilowatt hours by 24 hours we just cover the average load is three kilowatts so what we need to keep up with that is a battery charger that can put three kilowatts into the the batteries which you can easily get with a 50 amp short cord and if you really want to push your luck you can get close to it with a 30 amp short cord and in the meantime when the load is high on the AC side the batteries will get discharged and when the load goes down they'll get recharge and over the course of the day it will all balance out yeah 15 20 years on our boats and it works great yeah we we do those conversions for European boats the only challenge and you brought it is that when you're in colder climates where you're using you know and here it's not uncommon to have two heaters three heaters you know pulling 10 11 amps per circuit per heater at 120. you can easily offset uh the normal battery chargers because battery chargers are going to come pretty much the largest unless you stack them or 100 amps at 24 volts and that's going to be something but not enough so then you end up stacking more of them to offset so it's it gets tricky where that you need a constant heat that's the only challenge in my other climates like in your in Europe and stuff like that where it doesn't get too cold and you're not running too much heat too long it might be easier but yeah it's a limitation but a great solution though great solution to do it via battery chargers to inverters yeah very very neat yep it works well yeah so the isolation Transformer just to recap on that um so the other one too we also talked about also the fact that it sorts out polarity issues which is a real threat uh in destination marinas where it does happen where the neutral and the hot are reversed um that's also going to solve that problem so you you get two two wins with an isolation Transformer you you talked about the galvanic protection and then also obviously the reverse polarity and and I when I look at those things and you're right that the cons are absolutely the price the weight uh the volume it takes and the sound some of them so if you generally with the bigger boats you know the trawlers once you get around 40 45 50 for sure 60 feet they're going to have I session Transformers they're going to have one it's just the smaller boats you know the 30 40 footer you know is there a place and are you willing to spend the money the cost and are you going to get a boost transformer that's the other thing too which makes sense in the destination Marina so those are all different factors that play on the shore power one last question on grounding um and I get this all the time the isolation Transformers we do have um high frequency Transformers in the marketplace now which are a lot lighter um and then we've got just recently we've seen the introduction of um toroidal Transformers that you can tell them because they kind of round like a donut um which tell us about this one don't what's that I think they're in Connecticut okay they're fairly recent they don't comply with some of the ABC requirements in terms of shielding between the primary and secondary windings they can't because of the way they're built so fundamentally I think we're likely to see a change in abyc standards to catch up with the technology but I can't say that for sure um but they they certainly are pretty good as well and they're lighter and smaller uh so we are seeing some alternative Technologies in terms of isolation Transformers that that are pretty effective and do affect the same job but don't necessarily meet all of the prescriptions of the abyc standard which was written you know 20 30 years ago before any of these Technologies were available what's your thought on the pros and cons versus high frequency to low frequency for the isolation Transformer what's your trade-off in here sorry Jeff you're very faint on what the trade-off yeah I was wondering what's the trade-off in your mind between the high frequency and low frequency isolation Transformers I think it's all a largely a matter of weight I mean personally speaking I don't care how it's built as long as it does the job of the The High Frequency you know they they also it took several years before the abyc caught up with them um because they built very differently to a traditional Transformer and the standard was written around traditional Transformers that which isn't is interesting because um one of the things that we've tried over the years is to make these standards performance standards rather than construction standards because if you write a construction standard something has to be built this way and then technology changes the standard is basically out of date and it becomes an obstacle towards adoption of the new technology so if you write a performance standard you simply say that the Transformer or whatever it is has to be able to do these things and do it safely um so and I think that's a good example of where we wrote a construction standard which is basically an obstacle to getting new technology onto our boats and we're going to have to change it over time and and make it more of a performance standard um okay good point all right um anything else you want to share on isolation Transformer before we close off on grounds I just want to last one question on grounds I don't think so this is an issue that you get a lot of emails and feedback and I do too it's very confusing just because there's so many different grounding and bonding circuits on a boat and it's hard to know which one is basically driving the bus if you like at any given point in time but it's also essential to figure that out so that you make sure the conductor is is large enough to carry the worst case fault current it's going to see yeah my advice on that is to draw it out don't think that it's right and over time create a schematic for your boat and understand what size circuits are connected to what you want to obviously avoid the loops which can happen if you get too happy go lucky and you're just connecting everything to everything um I always think about you know a tree you know with the roots in the ground or one trunk and as it goes out one trunk to many trunks and then to Branch circuits and smaller and smaller as the way I look at it but the challenge in the question I was going to ask you Nigel was most boats don't have even a ground labeled on the boat most other than AC on the DC side it's going to be called the DC negative it's going to be a distribution but I think the challenge is also that the builders are stacking multiple things and I do the same thing we're having one device that does multiple things but when we look at schematics online they're seeing as you talked about an AC grounding bus an RF grounding bus maybe a grounding bus for the through halls and on all underwater Metals there's going to have another one that's DC grounding and then they're going to be like well what's the connection to ground is it going through the engine is it going through a plate how am I going to do my connection to the ground do you want to talk a little bit about sort of like lessons learned from your side on the implementation of what the ideal is because I think that's the largest hardest part is there's no place on a boat that even has those labels people don't know where to start they have to almost interpret or interpret what they're seeing what are your thoughts on that so I think conceptually it helps to separate all the DC negatives that go to what the ABC likes to call abyc likes to call a DC main negative bus so that's the negative side of the the DC circuits and they all end up at the DC main negative bus and then conceptually we have the grounding bus to which we tie the AC grounding conductors and any bonding conductors for lightning or Corrosion Protection or any DC grounding conductors those are not the DC negative they're the ones that might that are attached to the case of the inverter for example so we conceptually we have these two separate buses in practice if we have a a boat on which the DC negative side is grounded which the vast majority of our boats that's how they're wired then we confuse those two buses so we don't need two separate buses so we can take those cassette conceptually separate buses and turn them into one bus and that's what I have on my boat on the other hand if we have a boat with an isolated ground and isolated negative side on the DC side which we do have on on some boats we call it isolated or floating ground um so then the DC negative side is not is deliberately not wired to the boat's grounding circuits right so then we absolutely do have to have the two separate bus bars we have the the DC main negative bus which is where all the DC negatives go and then we have the grounding bus which is where all the grounding and the bonding and the lightning protection goes and those two have to be not only physically separate but they have to be electrically separate and that way the DC system itself is now a floating system on the boat it has no connection to the grounding system or to the water anywhere on the boat and in fact typically if you're going to install one of those systems you want a device which can detect if if that isolation gets voided in some way and will alert you to the fact that the isolation has been avoided normally speaking we only put those kind of systems on metal boats as an additional Corrosion Prevention measure and in fact they they do that in Europe way more than it's done in the states and I think the abyc would argue that in actual fact it doesn't provide any more Corrosion Prevention than a grounded system if a grounded system is installed properly okay yeah that's a good little recap I mean too much yeah that's good no that's good I mean it's a hard topic right I mean you're right I mean I think the the term you use is conceptual right like you're right it's these on the piece of paper you might conception they're separated but in reality on a boat you're gonna have these multiple connectors that do various things most likely all connected to one place yeah another way to think of this is the um all of the conductors that are attached to the the DC main negative bus are current carrying they're the negative conductors they're the return path on those circuits all of the conductors that are attached to the grounding bus are normally non-current carrying the only carry other than a very small currents we might see with galvanic circuits but we're talking milliamps a few milliamps um so so the one bus is dealing with the current carrying circuits and the other buses dealing with a non-current carrying circuits and then those non-current carrying circuits all the grounding and the bonding circuits the only time they carry current is if there's a fault in the system and then those two buses gonna as I said before can be combined on a boat with a grounded DC negative um but conceptually the big differences between those that are current carrying and those which are not so if you're curious again go on our website and find out more answers and solutions with this sort of setup and thanks for asking and thanks for all of you for listening and tuning in English (auto-generated) Videolytics    To