Adam F Posted February 17, 2005 Report Share Posted February 17, 2005 As you know I need to rewire BW. Quck question. I obviously need to connect the battery +ve and -ve to the instruments but not too sure the best/proper way to do it. Before the +ve and -ve went into seperate junction boxes and then the instruments were taken into here to get their power. I could also just wire the + and - to the buzz bar on the switch board, but this would make it very busy and also the connections would be bare. I hope I have explained this clear enough?...any ideas? AF Quote Link to comment Share on other sites More sharing options...
Newboy Posted February 17, 2005 Report Share Posted February 17, 2005 Not sure what you meant, but I wired Sweet Honey as follow. I take the +ve and -ve from the battery to a pair of terminal blocks. From these blocks, I run gps, ff, vhf and cabin light straight off it (all fused). A switch panel also runs off the blocks, and from there, nav lights, anchor light, horn, pump,.... Quote Link to comment Share on other sites More sharing options...
Newboy Posted February 17, 2005 Report Share Posted February 17, 2005 The cables from battery to terminal block need to be fairly big to handle the load. Add up the loads from all the equipments. I can't remember what I used but something around 30-40a. Quote Link to comment Share on other sites More sharing options...
Adam F Posted February 18, 2005 Author Report Share Posted February 18, 2005 Kam, Thats exactly what I mean - well done. What is a terminal bar? What does it look like? and where do I get one? Adam Quote Link to comment Share on other sites More sharing options...
duncan Posted February 18, 2005 Report Share Posted February 18, 2005 The positive 'terminal bar' is a little superflous I would have thought, and if it's reasonably accessable the switch panel input would act as the AUX feed for individually fused items. You aren't gaining anything interference wise with an additional bar. Do make sure you have a battery switch to isolate any disconnected electronic plugs and avoid corrosion. Do make sure the bilge pump is wired outwith the isolator - even if it's not automatic. Quote Link to comment Share on other sites More sharing options...
Newboy Posted February 18, 2005 Report Share Posted February 18, 2005 Adam: a terminal bar/block is a small plastic coated metal bar/block with lots of holes, for the wires to be connected to, it's one solid bar i.e., single pole. You can get them from the auto elec web site I posted to your original rewiring thread. Or if you can't be bother to order just one item, you can make one up. Go to any diy store and get one of those white connecters, they come in a row of about 10/12 poles and you cut out 2 at a time, using it to join a 2 core cable. All you do is connect all the metal holes with a thick wire/cable and making it a single pole. Duncan: I was lazy and didn't draw the battery bit better, yes, it should have a isolating switch from the battery. The pump is also wired direct to the battery (fused) for auto activation. Not sure why do we need a sperate isolating switch for the pump. Obviously you want it to work it's at sea and the battery gets disconnect when parked up. The reason for a terminal bar is that 1) the switch panel has only 6 switches and I have 8 elec and rising 2) easier to wire gps, ff, etc to the terminal than it is to wire them to the panel, in my case it's slightly tucked away. The only problem I can see is the bare terminal, if a wire comes off and touch something and sparks, but I got a bit of stickt tape and taped over it. Quote Link to comment Share on other sites More sharing options...
duncan Posted February 18, 2005 Report Share Posted February 18, 2005 by outwith the isolator I didn't mean it should have it's own - simply that it should be direct (as yours) but also direct even if it's switched rather than automatic - reason being that it is not unusual for someone else to become aware of a problem when you are not aboard and look to switch the bilge pump on for you - difficult if it's circuit is isolated! You will leave the boat afloat at some stage - even if it's only for a quick drink at the Banks Arms to celebrate that huge bass when you land it!!! Re +ve bar - understood completely but it;s not good practive to have an exposed +ve terminal of any size for a whole load of reasons. Extending, expanding, enlarging etc the input terminal to the switch panel is the normal way to go on a small boat - also easier for anyone to understand when looking at the wireing. A negative bar doesn't have the same issues and, in any event, the engine etc act as exactly that anyway! Quote Link to comment Share on other sites More sharing options...
Newboy Posted February 18, 2005 Report Share Posted February 18, 2005 The pump is wired via the switch panel and isolater as well as direct to the battery, so do I still need a 'direct switch' to the battery? Quote Link to comment Share on other sites More sharing options...
duncan Posted February 18, 2005 Report Share Posted February 18, 2005 if it has an auto switch (which your earlier post suggests) then no. I was simply highlighting 2 cases in the last 3 years where small boats (afloat) had problems - 1 leak - anchored gone to lunch, 1 heavy rain - mooring; and in neither case was anyone able to simply switch on the bilge pump (neither was auto). The former was beached (battery switch very well hidden - deliberately - in a locker!) and the latter bailed (with some choice swear words). The beached boat crew bitched really strongly at the people who had eached their boat as it was hi and dry for many hours (if they hadn't had a right royal go it would have been a simple matter for a group to pick it up and re float it but everyone just walked away in disgust! Quote Link to comment Share on other sites More sharing options...
Paul D Posted February 18, 2005 Report Share Posted February 18, 2005 Kam, Your description of the terminal bars is exactly the way Neo is wired. The +ve feed goes to a small terminal block which then feed the switch panel via three fuses ( fuse per two switches - obviously skinflinting on fuses ). The negative feed is sent to a larger series of blocks which are jumpered together using heavier gauge cable. Since one fuse is feeding two switches I would like to say I have carefully selected what items from GPS/FF, Steaming Light, Nav Lights, VHF, Bilge Pump and cabin light are fed by a common fuse( but I cant ! ). The switch panel fuses I have are higher current rating and the GPS and VHF have their own inline fuse ( ie. Delicate electronic equipment needs protecting ). The main feed to the two blocks is connected to the battery 1-Both-2-Off switch which I always forget to switch to OFF once home ( no problem with corrosion etc. through as the GPS connector is switched at the switch panel. ) The battery 1-Both-2-Off switch is connected to each battery positive terminal using car starter motor leads ( cheaper than "marine" alternative ). Hope this is of some help. PS: Wiring on Neo could also do with a good tidy up though ! Quote Link to comment Share on other sites More sharing options...
Adam F Posted February 19, 2005 Author Report Share Posted February 19, 2005 OK - Thanks for the advice. I have all the bits I need, and have constructed a wiring diagram - this this correct? Quote Link to comment Share on other sites More sharing options...
Paul D Posted February 19, 2005 Report Share Posted February 19, 2005 Adam, I will check how I wired teh battery isolation switch but I am 99% certain you can make life easier by joining the two batteries negative terminals together using thick "jumper" cable and then run a single feed to the negative busbar. ( ie. Negative part doesnt need to go anywhere near the isolation switch. ) Quote Link to comment Share on other sites More sharing options...
Adam F Posted February 19, 2005 Author Report Share Posted February 19, 2005 Paul Its already in - and the battery switch requires both inputs. Adam Quote Link to comment Share on other sites More sharing options...
Newboy Posted February 19, 2005 Report Share Posted February 19, 2005 I'm with Paul on this one, all the selector switch I'd seen has only 3 terminals. Also where do you put the outboard leads? I bolted mine straight to battery 1, so it's always on, i.e., can't be switched off by the switch and therefore will not damage the rectifier on the outboard if it's accidentally switched to off. Quote Link to comment Share on other sites More sharing options...
Paul D Posted February 19, 2005 Report Share Posted February 19, 2005 I connected the outboard leads to the switch. Granted it could potentially be damaged if the switch is switched to OFF whilst the engine is running, but I make a point to avoid doing this. The downside in your other arrangement is it will fail to charge battery 2 if switched to "2 only". Not much in it I guess, since I usually steam out with switch in "BOTH" position and switch to 1 or 2 when I get to the mark ( when I remember ! ) Quote Link to comment Share on other sites More sharing options...
Bob F Posted February 19, 2005 Report Share Posted February 19, 2005 Adam, Here's the article I wrote a while back. cheers BF Quote Link to comment Share on other sites More sharing options...
Adam F Posted February 20, 2005 Author Report Share Posted February 20, 2005 Thanks guys - yep, I was wrong, that is how much switch is connected - just had a look this morning. Im not re-wiring this part as I did this back in the spring when I got the boat - im juts doing the instruments and the console. Paul D - Can we put Bob's battery article on the site as a link? - Its a cracking piece and very helpful. Adam Quote Link to comment Share on other sites More sharing options...
duncan Posted February 20, 2005 Report Share Posted February 20, 2005 here's the same file as a pdf, and a lot smaller for it. Quote Link to comment Share on other sites More sharing options...
Paul D Posted February 20, 2005 Report Share Posted February 20, 2005 Adam, Can link to the article. Does anyone have any ideas where they would like it to be put on the site ? Under information ? I will use Duncan's PDF version. Quote Link to comment Share on other sites More sharing options...
Manic Moore Posted February 20, 2005 Report Share Posted February 20, 2005 Bob, that made good reading as I am also in the process of tidying up my wiring and possibly adding a second battery. In the artical you made reference to a method using relays. My engine is about 19 years old, but I don't plan getting rid of it before I trade the whole kit in in a couple of years. It would seem an economical way (and practical) to make the upgrade. Can you point me in the right direction & how would I find out if the motor had the correct signals? Regards Batteryless Moore Quote Link to comment Share on other sites More sharing options...
Paul D Posted February 20, 2005 Report Share Posted February 20, 2005 Another interesting question is what gauge of wire to use to run from the battery switch to the busbar at the front. I am 99% certain the wire used on Neo is far to lower gauge ( which would explain the voltage drop when transmitting on the VHF ). Opinions ? Quote Link to comment Share on other sites More sharing options...
Bob F Posted February 20, 2005 Report Share Posted February 20, 2005 Gordon, I've updated the battery document to show the relay method. This disadvantage of this method is that you do not have the flexibility to use the second battery to start the engine, or to use the starter battery to run the aux instruments. My advise is to keep things simple and flexible, and so use the method shown in Diagram 2, using a battery selection switch. Adding relays just means another thing to go wrong, and I prefer the option of using either battery in an emergency. Paul, yes, your main power feed cables may be underated. This would cause the problem you describe, but it could equally be a resistive connection somewhere. Was the problem there right from the beginning or did it develop over time? If it developed later then I would suspect a bad connection. What size cable should you use?? I would had up all the max current ratings of your various pieces of equipment, and then double it for safety. This will then give you the current carrying capacity that you need for your main feed to the aux equipment. NOTE - the connections between the two batteries and to the battery selection switch and engine should be at least 300A. If you use smaller cables between the two batteries the wires could melt when you try to start the engine from the second battery. cheers BF Quote Link to comment Share on other sites More sharing options...
Adam F Posted February 20, 2005 Author Report Share Posted February 20, 2005 I have 30 amp cable between the batts and terminal. But Gordon and I just added up the total amperage of the electronics on BW and it didnt even come to 10 amps in total!! Quote Link to comment Share on other sites More sharing options...
Maverick Martin Posted February 20, 2005 Report Share Posted February 20, 2005 Paul How about having a page under the information heading similar to the links page, you click on it which gives you a list of articles, select the required article and it opens. That way if any other reports are written it would be easy to add them. If the name is kept non specific, perhaps"articles" or similar then all informative items written by members could be added there. Martin Quote Link to comment Share on other sites More sharing options...
Bob F Posted February 20, 2005 Report Share Posted February 20, 2005 Adam, You need the 300A for any connections from the batteries to the engine, so that the cables are able to cope with the starting current. The cables from the batteries to your aux equipment can be less, depending on what equipment you have. If all your equipment adds up to 10A, then fit 20A cable from your batteries to the bus bars. The individual feeds from the bus bars to the instruments can then be smaller wires appropriate to the max current rating of the piece of equipment. cheers BF Quote Link to comment Share on other sites More sharing options...
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