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jeff cote here with boatingtechtalk.com  so we've got a question from a fellow  boater and this boater asks  jeff thanks for all your videos quick  question on battery  discharge and protection is it a good or  bad idea to use a  low voltage disconnect or otherwise  known as lvd  lima victor delta  well that's a good question so let's  start from a higher level  all of us on boats really deep inside  wish that the electrical system on our  boat would be a little bit more  automated  and that we wouldn't have to be at the  heart or the center of the electrical  system to manage power  and do all these different things to  make sure that our electrical systems  stay safe reliable and don't get damaged  one of these things our responsibility  that all boaters have is to make sure  that your battery bank does not get  discharged  too deep right we know that that there's  a  huge price to be paid to bring a battery  down from  full down to maybe you know 10 even 20  percent  all the way down to zero percent which  is about 10.5 volts for a 12v battery  we know that and as boaters we're trying  to prevent that we're trying to not go  to full empty tank  same thing we do a car you know you want  to give a cushion and the cushion  on most batteries is 50 agm might be 30  firefly might be 20. lithium is about  the same thing but we have a cushion so  you get full  alter a certain point and then you give  yourself a little bit of safety these  low voltage disconnects  are devices that will actually  disconnect the load  whenever the voltage triggers to a  certain set point  sounds great the challenge is  when you start automate automating  certain things on your boat especially  electrically  you're taking yourself out of the  equation and those lvds  low voltage disconnects are always going  to be triggered regardless what's  happening on your boat at a certain set  point voltage  so if you say for example i want my lvd  to disconnect at 11.5 volts or 12 volts  whatever that number is  there might be a circumstance later down  in the future where you know what maybe  you're now damaging the batteries but  you have no choice you're doing it  because  you know things are crazy your bilge  pumps need to run you know you're  leaking you're taking on water it's bad  seas you need to communicate  there's an emergency that's happening  that is you are deciding as the operator  to tolerate  a lower discharge voltage because you  don't care  the most important thing to you is to be  able to run the vhf run the bilge pump  the challenge with these lvds is they're  going to disconnect your batteries  whenever you want it or not at a certain  voltage  and that's where i have a hard time i'm  not saying it's not a good idea but as a  boater i'm going  that's giving a lot of responsibility to  a dumb device because that dumb device  is black and white  there's no sort of ambiguity to if it's  going to do it or not and it doesn't  understand context  it's like oh you're out at sea you're  running the bilge pump oh i won't  disconnect your batteries  oh you're doing something important and  you got a mayday and the battery voltage  is going down oh i'm not going to  discount your batteries no no it's like  every single time that the battery  voltage goes to x  whatever you decide x to be 10.5 11 11.5  whatever that number is  i will disconnect your loads so  the reality is i've never chose to  install one  i know they exist but i'm always  hesitant to give away that amount of  control  to a device to protect my batteries and  i figure you know what  i'd rather damage my batteries than ever  have a situation  where my batteries are disconnected from  a load  because some device which i put in there  to protect  me from disconnecting the batteries does  so in a time of emergency  and where i cannot afford to have loads  disconnected  so then some people say oh i'm going to  do so only certain loads so  i won't disconnect big pumps but i'm  going to disconnect and i'm like  disconnect what like a char plotter  would you disconnect a chart plotter and  actually to have it turn off if the  voltage got to 11  i would say no so then it allows you  okay what about water what if your burn  and you need water to put it on the  wound so you're going to disconnect your  water pump because now the voltage is at  11. you remember it's  it sounds like a great device but the  applications for it  it depends some people like automatic  generator starts  and some people don't i'm in the camp  that an lvd  sounds great i thought about doing it  but i'm just always worried about the  permutations when i actually need to be  connected to the battery regardless of  what it does to damage my battery  and an lvd low voltage disconnect would  remove that ability from me that control  and i can't do that so that's why i  never have installed it or i never  recommend them  but hey it's an opinion there's going to  be a bunch of people are going to post  their application let us know down below  how you're doing it on your bow why you  like it  and then maybe i'll change my mind so  thanks for watching  thanks for watching this video and we'll see you on  the next video  English (auto-generated)  Videolytics      Tools