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[Music]  good morning everyone good morning thank  you for a Bluewater cruising Association  for hosting this event the purpose of  the code and I try to emphasize that  yesterday is to keep us safe for some  weird reason and I'd love to understand  why people are willing to tolerate a  higher risk on a boat than in their home  home and you think about a home has a  lot of escape routes windows multiple  doors right it's pretty good  second-story I mean there is exits in a  home quite a lot of them house catches  on fire it's pretty bad but you can jump  through a window break up some legs but  you're on ground and you're pretty much  safe how many doors are your boat half  or companionway or hatches and how many  exit points you have on your boat and  when you jump off your boat are you in a  safe place  at that moment so you sit back and  you're wondering why would the bar be  much lower for a boat when it's actually  the worst place to be I mean we're never  in a safe place on a boat  you're not rarely tight at the dock and  even if you are that's not sure yes  you're you're close to it but you're not  on it and the code in the marine world  is there to protect us so that we don't  have these horror stories because my  point is we're all pleasure boating this  is not a means to die it's a means to  simply enjoy ourselves right and we're  not making a living on our boats none of  us are out there saying well I got to  feed my family so yeah my fish boat is  crazy but hey I got to put food on the  table and I can't afford anything else  and I'm gonna make it work right we're  not doing this out of necessity  it's a pleasure boat and so following  the codes is utterly instrumental to  have  of a predictable and safe experience on  your boat do it right the first time  having done thousands of electrical  audits on boats I can tell you that a  lot of us are inclined to take cut  corners to get the job done  maybe dinner's almost going to be served  you have to leave the boat it's getting  late the projects taking longer than it  needs to your fustrated you've got other  things to worry about you got to go back  to work you've got to do something you  know someone's reminding you that this  is taking a lot more time than it should  and what happens is you tell yourself I  want to cut a corner now but I'm gonna  remember to do it right later the  challenge and the problem with that is  the later part never really materializes  and in the end when I come on a boat  it's it's a bloodbath I rarely come on a  boat and people are smiling when I leave  we go together through a well of despair  journey down through the bowels of  unhappiness come at the bottom and then  I tell them well there is a way to get  yourself back to the top but it's gonna  be painful and it's high amount of  financial burden and time and then we  hug it out  so almost a pep talk and then we start  slowly crawling or back to the land of  normal and the reason that happens is  because the majority of people are just  simply too busy don't care they don't  have the right parts they just want to  get it done and they want to get a  satisfies sense of satisfaction what I'm  here doing today is I challenge all of  us to not take shortcuts with electrical  systems it's sort of like if you're  gonna work on your brakes on your car  would be a prime example of not cutting  a corner on the brakes on your car you  know if you're gonna work on the brakes  on your car you're probably gonna want  to follow instructions do it by the book  because it's the brakes on your car an  electrical system is very similar so  first thing on a boat whenever you're  working on your boat or you're  retrofitting and you're  wondering should I keep this wire or  should I change it I actually see boats  from the 70s where household  electricians probably wired the boat  Tacey I've seen a bunch of boats from  the 70s that have solid strand household  AC wiring on the boat pretty rare  no builder would do that or maybe they  did but not a common builder today if  you've got AC wiring on your boat make  sure that it doesn't feel like a hanger  like if it's stiff like a hanger you got  to get it out there's no doubt about it  it's gonna be painful but it's just time  it's just time so just take the time to  do it and go through you want basically  multi strand wiring right as you see  here and notice how how many strands are  on this wire if you looked at welding  cable Weldon cable of this size would  have maybe 20 strands especially 20  small copper wires like this but a  proper marine grade wiring is gonna be  very flexible and it's gonna made up  thousands of these little little tiny  strands of water makes that because  remember boats are a vibration prone  environment and I remember being a kid  you do this enough with them a hanger  you're gonna be able to shear it off  clearly have a great cut without a pair  of pliers and over time that can happen  on a boat and so hence why they need to  be multi strand question question is and  let me try to phrase is AC wiring on a  boat solid or not  it cannot be solid not on a boat black  and white can't this is a rule it's sort  of like the Ten Commandments it's one of  the ten you cannot have a solid strand  of wire on your boat period if you do  and you'll see that you can clearly tell  what it is first of all I looks out of  place you're like me that wire looks  weird it doesn't fit in that's the first  thing and if you touch it it's rigid  like hell and you just know and  generally that happens when someone  decided to delegate a task to someone  that was at a rate that was too good to  be true  hey I can do this for you  it's gonna go at Home Depot buy a bunch  of wiring you know save you a lot of  money give you a deal you can pay me in  beer you know maybe we'll see or maybe I  can sleep on your boat for a night and  then give me a shelter and I'll work on  your boat and honestly you can't have  that you're gonna get in a world of hurt  you got to have multi-strand the other  thing too is about color coding for some  reason there is a significant portion of  the population that is colorblind or  chooses to be colorblind and those  individuals believe that everything is  context-driven  meaning they'll always remember that  that all black cables they remember what  their purpose are because they know what  it's connected to  and for them they think that codes are  stupid clearly I haven't met one yet but  I'd love to I'd like to have a talk  probably think it's stupid and they'll  wire all their boat with black wire  everywhere and they're like well listen  it's pretty obvious it's connected to  the positive post so why do you need to  have a different color for that and  that's true until you disconnect the  item and then you have two black wires  and you're looking at them and you're  like where does what go where  and sometimes with AC wire you have  three hours I've seen AC wiring three  wires black because it's context-driven  and they're right a wire is a wire  listen if you have a memory that you  will never ever forget anything ever  yeah that that'd be true but then you  can't invite anyone to ever work on your  boat you can't really pass on your boat  to another owner because they don't have  your memory they're not infused with  your knowledge and then it makes  troubleshooting an absolute nightmare if  you remove a part on your boat you got  to be completely paranoid because now  you're when you're gonna be reconnecting  it you're gonna be looking at the same  colored wire some of them don't even  bother to put heat-shrink on the to  color-code them and so you're just  looking everything's black and to them  probably they buy one wheel of wire or  they buy and everything  would I buy two wheels of everything  when I can buy one wheel and then that  way just wire the boat black and believe  it or not that is very common very  common on retrofits  there is a purpose for every single  color and it's the same it just makes  takes the guesswork out of working on  your boat here's a chart from ABY see of  all the different colors the ones that  really matter to us as boaters is yellow  or black is 4dc ground return negatives  right and red is main power feeds those  are probably the two most important ones  from there all you that's why your wine  harness on your engines different colors  right and all that stuff all those  colors are right here right you see that  a lot of engines for example orange like  on my Catalina they had that orange was  the AB meter to alternator they have  that you'll see brown you'll see that as  well  oil pressure blue but the real one when  you're working on your boat is red and I  love yellow not black yellow because  here's why in DC let's start with AC  black in AC is def right  it's def you touch a black wire EC your  your you're off you're going to the  other side you're going to the other  side is done right there's no you can't  touch a hot AC wire it's over because  you're probably standing on ground and  we've got a great voltage potential and  you're touching one twenty two twenty  and that's it your your your you're off  to the never side so that's pretty bad  and we all know that AC is dangerous not  a lot of bravado with AC on boats not a  lot of bravado most people I would say  have a high low risk tolerance with AC  most people are cautious the challenge  is that if your boat is black on the DC  black on the DC is benign it's ground  it's the most it's the safest thing it's  like standing on earth what's wrong with  standing in a grass field or  being in the water it's pretty it's safe  place and so you take black AC def black  DC is earth and now the only way you can  tell them apart is what they're  connected to or their wire size but the  challenge is on some boats the black EC  can get up to gauge six wire like a big  generator some generators go to number  four  so unless now you've got to have a rule  in your mind you're like if it's a  really big black I'm pretty sure that I  don't have a really large AC appliance  on my boat so it's gotta be DC but  anywhere from easily number eight or  number ten up then you're like well  number ten easy can be AC it can also be  DC and then everything is context-driven  what is it connected to is it part of a  cable which has three wires on it and  there's a black white and green but then  what gets even crazier is a lot of  people buy only one reel of AC wiring  and they'd wire all their DC stuff with  AC whine because they can't be bothered  to bidc whine duplex how many down  riggers  water pumps bilge pumps I countless DC  appliances have been wired in AC wiring  on a boat oh my god  it's not a hundred it's thousands  because they just have it and they're  like it's a wire it works and they're  right it does until you forgot what it  was doing touching black DC is benign  touching black AC is death hence why I  like to use yellow for DC so in our  trucks and our fleets all the wire we  buy for DC is guess what it's simply  yellow only it's why why would I not  make it easy for everyone and safe yeah  you would go the question is where would  you grab these color-coded cables you  would go to a Chantry the charts online  you can grab that online or you'll get  it for my presentation yeah  a B Y C has that  yeah even you know it's funny Western  marine actually or West Marine has a lot  of they're really helping they do it  yourself there's a lot of stuff on even  West Marines website they've got tons of  information because I mean they're  trying to fee that Do It Yourself market  right a little bit like Home Depot yeah  yeah they're really helpful I mean  they've got some really good stuff I  mean they're trying to help people cuz  you know I mean all of us at one point  have to do something on our boat and we  all do even if you know even if you've  got a good trades at one point you're  gonna be doing something on your boat  and you might as well do it right the  first time and so do it right the first  time guess what on my boat do you think  I have no wiring on my boat at all ever  no my boat is I have wires of all  different colors all different sizes  I have connectors of all different sizes  all fuses when I do a project on my own  boat I always choose the right wire the  white wire gauge the right wire color  the right connector everything is there  because I value my time time is the most  precious thing I have in life more than  money times always running out there's  nothing you can do for buy time other  than not waste it and that's why I  always do it right the first time  polarity on a bilge pump right we talked  about it  CERN things will literally blow up if  you reverse the polarity and I've  actually brought a bunch of multimeters  and we'll take them out a little bit  later but it's absolutely essential  essential that you don't screw up  polarity and if you're gonna work on  your boat and we're gonna talk a little  bit about multimeters in a while I  highly recommend that you get used to  measuring polarity on a wire I don't  even I doubt myself constantly bravado  confidence have no place on electrical  systems none when I connect two wires to  an appliance even if it's red and black  I take my multimeter out and I confirm  because I don't want to damage the  appliance I always measure polarity  right I measure 12 volts and I want to  have the right polarity red is 12 and if  I had it wrong and I put black the black  and red the red  and suddenly I measure negative 12 I'm  like well how the hell did that happen  but I never hope that it's right I never  assumed that it's right  I always doubt myself doubt is a good  thing with electrical systems you want  to have a lot of doubt it makes you go  slow but if so is walking a tightrope  you don't want to walk a tightrope with  tons of bravado misstep fall over you're  like well that was that didn't work out  confidence you don't wanna have too much  you want to doubt yourself go slowly so  polarity is absolutely essential a lot  of boats obviously red is red for DC a  lot of us are gonna have black if you're  rewiring something on your boat you're  changing something you know on my boat  Catalina did everything in black but as  I'm adding wire for anything if I'm  running a new wire to a new place I'm  running duplex red and yellow right  duplex is two wires in one cable like  for example if you see a power cord  extension that's a triple x right it's  got three wires in one cable duplex is  two wires and so you're running one  cable that is made of two wires right so  then anyway you're not you're you don't  have to buy a yellow wire and a red wire  you're buying duplex ready to yellow you  can buy duplex red and black but why  would you when you can buy red and  yellow we talked about this black is the  most dangerous you have to stay away  from black on AC it will kill you white  is neutral and ground is ground the  neutral is the return path on an AC  circuit and the green wire is the second  return path on an AC circuit sort of  like the shoulder on a highway so you  don't have a shoulder on highway you  should sort of freak out because if ever  you have a breakdown you're staying in  the lane and not everyone looks a car in  front of them and stops  we see that all the time if you don't  pull out you're gonna be get rear-ended  some people just drive and they're just  driving and they're gonna whatever is in  front of them just in front of them  that's how people die on the highways  when the car stops right in the middle I  wake you want a shoulder the green wire  is your shoulder it's another path going  back so that your circuit is completed  it's you're redundant path because  remember your neutral is grounded  somewhere right to be grounded and so  your ground is a path to ground which is  it past the neutral and if you're you've  got an open neutral somewhere you want  to make sure that you have another path  to ground  so it's redundancy and that's why all  these older homes that have two wire  systems are strongly encouraged to go to  three wire systems and yesterday we had  a question about generators you know  those little Honda generators well the  ground is useless you plug it in but  there's no ground there's no ground at  all you gotta love the British honestly  you gotta love him I got it I got to say  I would have loved to be in that room  when that conversation happened for sure  for sure it's one of my top 10 places I  want to go with a time machine when they  decided that zero is the biggest wire  and they were going to go with smaller  numbers as they went up you got to give  it to them that takes a lot of courage  that is whoever came up with 0 being the  biggest wire in their room and made a  decree will never have bigger than zero  because zero is sort of the start I mean  let's be honest we know what zero is and  they decided that it's going to be  actually opposite to convention that  takes a lot of courage god I wanted to  be in that room in North America because  we're so influenced obviously with the  United States working off the British  system wire gauges the bigger the number  the smaller the wire  which makes completely no sense and then  at one point you get to a zero gauge  wire which was probably the biggest wire  they ever anticipated at that time but  it's not big enough anymore so then what  happens how do you go bigger than the  biggest well then you go one OTT one for  its last zero to OTT 2/4 5:03 OTT 3 4 5  0 so if the numbering system is  confusing it's not your fault it's just  not your fault it's just not your fault  and we work with it because you know  it's so commonplace I mean you just  can't all our technicians that come from  Australia or New Zealand they're like  what though what is wrong with you guys  why are we not talking about millimeters  like wouldn't that be easier just  measure the diameter and let's just go  with that the bigger it is the bigger  the wire is oh my god but that's way too  easy you need to translate so wire sizes  you can actually see this was ten to  twenty eight but this 10 goes eight six  four two zero one ought to walk three  OTT Faurot and four odd is not the end I  mean that's just what's reasonable on a  boat it's about the size of a thumb  right inverters are gonna be generally  wired on to ahtur for OTT the 2000 watt  inverter is about two OTT a 3000 watt  inverter is a four OTT and then when it  gets bigger than that then we start  running parallel four rods like a 5000  watt inverter we're gonna run double for  oughts  because we have more amperage going  through that wire okay so the smaller  the wire the thicker the wire  okay from here to there you had a  question before the reason why you size  for a large wire is that you want that  wire to not overheat for carrying those  amps right and that's how they raid a  wire so for example in 14 gauge wire for  AC that's pretty much how all our ohms  are wired 14 3 gage 14 wire 3 wires hot  neutral ground so it's called a cable  xxx 14 3 but it's made of three  individual wires  that wire is 15 amps you can run that  wire at 15 amps no problem without that  wire overheating okay now there's other  constraints is it running through an  engine room is there gonna be wired in a  bundle there's a lot of variables that  affect wire size but if you're looking  at ampacity alone a gauge 14 wire can  handle 15 amps continuous no problem  so as you install larger and larger  appliances on a boat one of the  variables we choose for choosing the  wire is the ampacity table okay and it's  not the only one but it's one of them  okay and we're going to look at wires  that have more amperage going through  them than they can handle and that's  where those wire bundles and you hear  those stories it happens happens all the  time  happens right here in the summer you  hear about boat fires I get called on  all the time and get to see them for  surveys or retrofits like fixing the  boat and generally it's because of a  dead short and the wire was running more  amperage than it could handle and it  caught on fire and then the whole bundle  caught on fire and then until the  battery switch was disconnected you know  there was a lot of damage on the boat or  the whole boat window now the other  variable that you choose a wire on is  not only ampacity but voltage drop and  that's why in Europe they did 220 and in  North America they did 120 but at 12  volts remember what we said at the  beginning of this presentation I  emphasize that a full battery is twelve  point six and a half empty battery of 12  volts is twelve point two point four  volts that's not a lot of margin right  that's not a lot of margin that's a  pretty tight that's that'll there's not  much there  so when you're running East DC wiring on  your boat and you're going from your  battery banks that are at the aft of the  boat and you're running a windlass at  the bow of the boat or your nav light on  top of a mast it's connected to the  battery bank you're having some crazy  wire runs on a boat and certain  appliances through a B YC are going to  say  3% voltage drop so it's gotta be 3% or  better and some are gonna be 10% or  better but you know what a wire to be so  long that by the time you get to the  appliance you've lost so much voltage  that the appliance won't work when the  batteries are at 50% of capacity or god  forbid maybe for whatever reason now  you're at 11.8 on your battery bank  you're at 25% of capacity but you gotta  run it and if you have large voltage  drop then those appliances imagine your  anchor light stops working at 11 8 that  would be disconcerning right I love an 8  I lose my nav lights well that would be  pretty serious I mean you don't want  your nav lights to stop working at 11.8  volts on your batteries but if you've  got undersized wires and it's a hell of  a run maybe it gets that by a time it  gets to the appliance it's only 11 volts  10.5 and then suddenly that appliance  load doesn't work and now your nav  lights don't work when you have low  voltage hence why nav lights are 3%  voltage drop because you want to  minimize the voltage drop on the run  from your batteries to the appliance  longer the wire the more the resistance  right result of voltage drop is devices  won't work and the way to offset that  voltage drop is by getting a larger wire  hence why when I do an install I don't  work anymore on both sigh just provide  guidance but our team does we always err  on the side of caution we're not gonna  do something to the minimum because it's  a waste of my time the owners time I'm  always gonna go a size bigger I always  play safe and I'm always gonna do it  through the calculation and blue sees  for example a really good company out of  Bellingham in Washington State has an  app you can literally include what's my  wire length is it going to be an  intermittent or fixed load is it going  to go through an engine room you can put  all those variables in and it's gonna  tell you what your voltage drop is gonna  be and what the ampacity of the cable is  and it's gonna tell you what cable you  should choose for that application so  you don't even need to use a table  anymore you can actually figure it out  on an app on  this is the table blue C's did it it's a  great because they're combining both  voltage drop and n pasady on this table  ABY C has one that's just voltage drop  and then ampacity and you're supposed to  choose the bigger of the two here  they're actually made both so whoever  kudos whoever did that I mean it's just  it's even beautiful honestly like who's  I mean you look at that you're like  whoever brought that to the boss it was  like so proud of himself or herself like  I did it can I go home now for a week no  that's just amazing  look non-critical loads 10% critical  loads 3% the length of cable total run  right not just going there but coming  back and it's not like oh yeah my  windlass is my batteries are a midship  my batteries are forward it's 15 feet  because I have 30 foot boat no it's the  path the wire takes to get there because  as we know there's no direct path  between anything on a boat well there  could be but you'd live in a rat's nest  it'd be like Southeast Asia right like I  travel there recently and I mean the  wiring there is just like you need to  take a chill pill you need to go like  it's okay it's not home it's gonna be  fine stay awake but in our boats we're  wiring wires everywhere right to get  from A to B you might its way longer  than the direct distance between those  two points it might be 15 feet direct  but it might take you 30 feet to get  there and then 30 feet back right so you  need to calculate the overall and if you  miss the back your wire length is gonna  be wire sides gonna be completely back  wrong so you absolutely always need to  go what is the length of the cable going  to the for example my nav light anchor  light and then from the anchor light  back so you always got it to twice going  and back and that's the length of the  conductor or the wire circuit length  okay pretty much you can see everything  the biggest wire gauge you can do is for  out on a boat and then bigger than that  then we start doubling them up on the  large inverters will start having double  for odd  this is an example of an anchor light  right so the batteries right here and  you've got to go all the way over here  and back so you got ten foot at the  bottom forty foot but then you forty  foot down plus ten you got a hundred  foot run and again you look at this and  you say oh it's a critical load so you  come down over here forty feet right you  know it's a 5 amp load right let's start  yeah a hundred feet sorry all the way  sorry my bad 100 feet 5 amp load yeah at  least six at least six yeah now anchor  lights don't draw five that's why  they're not as big right an anchor  lights one amp right two amps now LED  lights are like 0.1 amp right that's why  I also think about this it's also why  it's always eating retrofit LED lights  instead of halogen bulbs for example or  incandescent right you don't have to  worry because you're doing a fraction of  what it was like if you've got a halogen  bulb it's like one and a half two amps  per bulb at 24 at 12 so you change that  out to an LED bulb you're at 1/9 of that  number right so the wire is a huge  overkill but you're not gonna make  you're not gonna remove the wire because  it's too big it's not worth your time  but you never have to worry about going  to LED to replace an incandescent bulb  or halogen ball because it's it's a much  it's a fraction of the load well there's  a list of critical would be like for  example nav lights VHF radio would be  critical non-critical would be certain  things that you don't care like maybe a  water pump right bilge pump is gonna be  3% so things there's a whole listen EBU  I see they've divided it and up things  that you really care about things that  don't matter like cabin-like 10% that's  a really good example bilge pump is 3  nav lights 3 anchor light 3 right VHF 3  things that you absolutely need and I  know most of us think that we need  everything on our boat but we don't  really need everything we just select  the thing that we do but we don't need  everything on our boat  so here they're the example they're  doing non-critical would give you 12  fuses what's the purpose of a fuse or a  circuit breaker on a boat it's the means  by which we protect the wire from having  too much current okay does that make  sense I'm just gonna show you a quick  video about the importance of few sighs  no fuses and fuse location  okay so here we're gonna create a short  circuit and we've got a fuse close to  the battery is that a good thing or a  bad thing a fuse close to the battery  good thing it's the start of the circuit  right think about our homes the circuit  breaker panel in your home is not for  convenience it's a coincidence that it's  convenient it's there because it's the  start of all your electrical circuits  it's gauge 14 wire this is we're gonna  cause a short and that's a like what  happens when you cause a dead short  downstream of a fuse some sparks same  shot light goes off right so we have a  fuse at the beginning of the circuit  we've got a light and we had a dead  short all good what happened to the fuse  she blew right so fuse is gone so now  what happens was it became an open  circuit right remember we talked about  that light it has a resistance that's  why there's a limited amount of apps  that goes down positive back to the  negative okay  this is a typical install VHF radio fuse  only near the appliance  okay got it we've got a positive wire  negative wire coming down notice there's  no fuses yet no fuses yet we've got a  short before the fuse could have been  anywhere here's the light what happens  twelve volts that's a gauge 14 wire  honestly from here from this wall to the  first table the cloud of smoke was  probably so uh pake  it was over sort of two doors wide at  least maybe almost a barn door garage  door  why not garage but between the three  doors French doors three French doors  wide completely opaque you can see  through it it was absolutely crazy  that's two feet three feet of wire gauge  14 having a dead short trust me you've  got way more than three feet of 14 gauge  wire on your boat that can dead short if  it happens in a wire bundle you hear  those stories people are the back of the  boat forget running your VHF radio this  is never gonna happen like you can't go  down and operate a VHF radio in that  dead short and when they get off the  boat I've heard stories the the amount  of damage that it causes to your lungs  I had it happen to a boater talked to me  at the Boat Show it's been three years  he has literally like lung problems he  had his generator caught on fire and it  was insane insane three years later he's  having tons of breathing problems from  breathing all that wire jacket that got  melted for this generator cause a short  so it's real okay it's not a joke and  that circuit by the way the diffuse blow  no fuse was intact because the short  happened before the fuse so fuse  location is not a joke it's not like oh  well you know I'm pretty good I've got  it wiring it's like having a tiny chain  link and the last four feet of chain  link to your chain you go the right size  it doesn't matter what you do that's  right it's what you do that isn't right  what's wrong is the problem being right  for a foot and being wrong for 50 ain't  good enough question so the question is  how do you get to fuse a bad or a fuse a  circuit at the battery  as you go forward from the battery every  single trunk circuit or big circuit has  to be individually fuse you'll have the  fuse from example from your battery it's  gonna go through maybe some sort of fuse  and then from that it's gonna go on a  large wire to your DC panel that fuse  might be 50 amps because it's a gauge 8  wire let's say and so that segment is an  aggregate fuse for that trunk line from  the battery to the panel from the panel  then you've got individual branch  circuits each individual one is gonna be  fused I don't care if they're in a  bundle I don't care if there's a hundred  I don't care if there's ten I don't care  if there's a thousand every single wire  that's connected to a source of power  has to be fused that's how it is online  if someone didn't do that on land it's  criminal  literally criminal it's not a slap on  the wrist something happens there is  maximum liability can't do it you'd be  fired your draw you lose your job you're  it's it's criminal on a boat it's a  choice and it's a choice that is badly  chosen constantly that's the crazy part  and unrelated we complain that boats are  unreliable we don't like that you know  we the risk tolerance but you know  boaters as boaters we have that decision  that's the problem with a voluntary code  you have to choose what is your risk  tolerance and like I said yesterday when  you buy a boat a used boat you don't buy  just a used boat you're buying the owner  the previous owners risk tolerance is as  important as the boat you buy if that  owner was a MacGyver and you're not in a  Guyver you're in a world of hurt now if  you're to MacGyver's and you're twins  hey no problem they don't care about  safety you don't care about safety your  boat match made in heaven but you're  always buying the previous owners risk  tolerance okay sometimes you'll have a  circuit breaker at the beginning of the  line and you'll have a fuse of the  appliance and that would be one way you  could have a fuse at the beginning of  the line if that fuse is exactly what  the appliance wants you can have just  one fuse for the wire and the appliance  there's nothing wrong with that right  you can do that like for example fuse  blocks would be an example you can  install a fuse block that fuses exactly  what you want like on my boat I don't in  self fuses ever at the appliance if  whenever it hits a fuse block I try to  aggregate all my fuse blocks in one  central location and the whole length of  wire from that moment on to the  appliance is on the fuse that the  manufacturer recommended for the  appliance and it also protects both my  wire and the appliance for example  because I don't keep on my boat my  circuit breaker panel would be a  standing room circuit breaker panel if  you had to see it that's how many  circuits I have on my boat because I'm  crazy I mean I love stuff and I got tons  of stuff and my boat has more stuff than  you can ever imagine but that's because  you know it's me  so my circuit breaker panel can't have  all those circuits so I don't turn I  don't have a circuit breaker for radar  or circuit breaker for char plot or  circle period for VHF a circuit breaker  for depth sound or a circuit breaker for  e is a circuit breaker for like my  second chartplotter my second depth  sounder like I like Ida cat can you  imagine it'd be a standing room like on  a swan 75 i rewired a whole swan 25 now  that was a standing room DC panel that's  the type of DC panel I need on my boat  but I've got a 36 foot sailboat and I  don't have a swan 75 so I have basically  distribution points I turn electronics  and it goes to the fuse block and that  fuse block has six or seven or eight  circuits and it energizes my nav  equipment same thing with lights I'll  have a bunch of lights but I have  individual lights off another fuse block  I'll have you know cabin lights  I'll have headlights and so I basically  basically like it'll be like a tree you  have a big trunk line other big branches  and then from branches share out to more  branches and that's pretty common on  most boats it's very rare that you're  gonna have a boat that's gonna have an  individual breaker for every single DC  appliance that you have on your boat  yeah the question is if you have let's  say a boat that has a circuit breaker  for every single DC appliance on your  boat then you would be able to install  only appliance defuses at the end or  near the appliance and all of your  wiring would be protected by this  breakers at the beginning of the circuit  but that is a big big if the question is  with DC appliances are the tolerance is  tight for fusing absolutely  manufacturers don't say I need a 5 to 10  amp fuse they're gonna say I want 7 amps  they're gonna give you literally a nap  they're gonna say I want a 10 amp fuse I  want a 4 amp fuse I wanted to amp fuse  you won't be able to find a circuit  breaker at DC that gives you that level  of granularity you can't doesn't exist  so you end up having to install the fuse  they that they supplied or that you  provide to at least protect the  equipment now you could protect it at  the beginning of the circuit if you  don't have a circuit breaker right and  that's fine or you can do it at the  appliance but then you need one for the  line as well the further you move a fuse  for the appliance closer to the  appliance you need a fuse at the  beginning of the circuit for the wire  well the breaker is the start and the  fuse is at the end of the appliance so  you'll have a lot of circuits you'll  have to skew cz's or a circuit breaker  and a fuse one for the wire and one for  the appliance you can combine both  together at the beginning right you can  but you're not gonna be able to find a  circuit breaker for that because it's  too granular in a lot of cases so if  you've got for example lighting is  question is I have 10 lights on a  circuit to a breaker does each light  need to be fused well it depends it  depends on what is the maximum rated  ampacity that that light is able to take  if for example each of those lights say  I'm going to need only 0.5 amps to run  but I cannot have more than 0.2 more  than 2 amps going through you can't have  a 10 amp breaker feeding 20 amps or  20-amp breaker feeding all those lights  if the maximum capacity of one light is  too much you can't now in most cases  that's not the case lights when they  burn out they sort of die and they die  with them there's no like the limitation  for a light is generally the wire going  into it  so for example Catalina again most boats  old light spotlights you know the wiring  inside would be the limiting factor so  if they were wired for 14-gauge inside  of the light that whole circuit could be  fused with a 15 amp circuit because  every wire in that circuit is able to  handle 15 amps so most cases most cases  99% of the time lighting circuits are  parallel right so you have multiple you  turn on a switch and a lot of lights  come on  that's okay they're in parallel and the  wiring inside of the fixture is able to  handle a lot more ampacity than the  rating or the amps of the light like for  example my fixtures of my Catalina we're  all 14 gauge light wires inside but each  light only drew a nap  so my breaker on my panel could be 10  amps the lights can all handle 15 and  each lamp only draws one app so I'm fine  there's not a lot of circuits that are  parallel on a boat right there's not a  lot there's not a lot lights are one of  them because otherwise you'd have  literally a single switch for every  single light on your boat and that would  be crazy I mean your panel would be the  size of a door okay any other questions  okay so this is the good one here  because this is what we were talking a  little bit earlier you got a big fuse at  the beginning of the circuit which  people always tell me oh I've got a fuse  of the battery I don't need fuses  anywhere else a smaller fuse when the  wire drops and we're gonna create a  short  okay there's a fuse right here you can't  see and there's a fuse here which fuse  blew the little one or the big one yeah  okay now this is probably one of the  most popular misconceptions that I hear  all the time is people tell me Jeff I  have a fuse on my battery I don't need a  fuse anywhere else in my circuit I hear  this all the time  bow chose a lot of people like to sort  of debate and argue and prove their  points and like I don't need fuses on my  boat because I have one at the beginning  of the circuit I'm like well if every  wire on your boat was the exact same  size and as big as the first wire that  connected that fuse you'd be right and  if every appliance would be able to  tolerate that amperage you'd also be  right but those are two big conditions  that never happen on a boat so we're  really talking about theoretical  situations that never have happened  ever ever ever because nobody's wiring a  whole boat into watt and not every  single appliance can take two on average  which is like 300 amps right I mean what  kind of boat would that be that'd be  sort of that's a theoretical boat but it  ain't a real boat so what happens now if  you've got two wire sizes but you don't  have a small fuse when you hit a smaller  wire it's got a big wire big fuse  smaller wire changes size now no fuse  you got a dead short on the small wire  what happens  that's exactly right the big fuse below  no it's 300 amps it's too hot wiring 300  amp fuse that was gage 14 wire gage 14  wire 15 amp maximum capacity  no fuse there the wire can only take 15  obviously can take 20 it's probably  getting warm but at 1.15 is what's  reasonable and at one point would have  been cool I should have put a clamp on  meter see how many amps did it take  until they blew that would have been  good one but the wire so the wire was  fused literally it was fuse but it was  the wrong fuse right fusing a wire is  not good enough putting a 400 amp fuse  or like I'm no joke this is a true story  literally pudding for example I've seen  this where people are putting like  you've seen this in pictures probably a  coin to replace a circuit breaker right  that happens it's not people don't make  it up while putting a coin to replace a  circuit breaker  that's not a fuse that is a dead short  it's it's a replacement and you're  basically bypassing the circuit breaker  but it doesn't certainly replace it and  so if you've got a three hundred amperes  on a 14 gauge wire that fuse will never  blow you'll never have to replace the  fuse but the boat right but the boat so  it's really important to remember to  always worry about fusing both the wire  and the appliance and under certain  circumstances you can do both with one  device or one fuse at the beginning if  that fuse at the beginning is going to  give what the appliance wants and what  the wire wants right on new builds and  stuff like that it's generally a circuit  breaker for the wire and a fuse for the  appliance they're gonna do it like that  but then you got to chase the fuse you  got to know where that is  right because the breaker is on and off  but your VHF doesn't work and sometimes  what they do the VHF you know might the  wire might be this long and the fuse is  buried Wady  you're pulling up the VHF and you don't  have power you're like my breakers on  there's power on the other side of the  breaker and I don't have power there  where the hell is the fuse and then you  got to look for the fuse right and  that's time-consuming  okay so basically you sized a fuse to  handle both the load and the wire gauge  and you don't want usin stripping the  point was you generally have the  manufacturers figure that number out but  if you don't know generally you give  yourself about 25 percent like for  example if I'm fusing a battery charger  that it's a 40 amp battery charger I'm  gonna fuse the circuit for 50 amps I'm  gonna make sure that the wiring can  handle 50 amps and I'm gonna put it in  I'm gonna put a 50 amp fuse in that  circuit so that the battery charger  never has nuisance tripping you want to  make sure that you protect the positive  energized post on a fuse you see a lot  of times with fuse blocks that covers  off and then you've got exposed positive  connections any positive connection on  your boat should be capped because if  you ever accidentally touch the fuel  tank a fuel filter that's metal to a  positive post and you're doing it on the  battery side you're gonna have a dead  short so you always put a cap on all  positive circuits same thing with for  example on all our alternators or  especially on all alternators we should  have a positive battery cap on all of  them you know a little cover there like  five dollars two dollars there you see  them in our cars you open the hood of  the car all the connections that the  batteries have a little cap on there and  generally they're peeled over now put  back right because people find them  annoying always carry a spare fuse and  choose a thermal circuit breaker  recommended by the manufacturer right  use as a switch a lot of people use  circuit breakers as switches for on and  off they're convened right that's what  panels are right they're circuit breaker  circuit breaker and it's also a way for  you to disconnect or connect a load to  an appliance we don't do that in our  homes nobody's going to turn on the  bathroom lights by going down in the  basement and turning it down on there  but on a boat a lot of cases there's not  another switch further down free like  we're start your nav and you'll have a  net radar breaker its radar breaker  power and there's not a radar switch  later on that both energizes the device  and powers on there's not a secondary  switch later on because our breaker  panels are not bowels of a boat  generally they're not that far unless  you've got a mega yacht and then  everything's down in the engine room and  then yes you'll have other switches  later on but most of us are gonna have  everything happen at the DC or AC panel