I have uploaded a PDF document and am looking for comments on my 12v wiring layout... Please note that I have not shown any accessories off the panel at this point. Thanks.. Jon
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Comments wanted on New Elect Schematic
- Thread starter PGIJon
- Start date
The mono coloring of wires is very confusing. Also what are you trying to achieve with two 1/2/Both switches?
Pertaining to the older boats with a single battery selector switch like my '85 H34, I went with the two 1/2/both switches as it was less real estate used versus three on off switches to achieve full crossover capability and I got the ability to turn off the engine start function even if using the engine battery to power the DC distribution panel. I just never wanted to leave it to chance that someone could hit the starter button or I could short the solenoid by accident while working around the engine. Also, I think there is an economy of only purchasing an additional multi-function switch (since the boat already came with one installed) rather than two more on-off switches for the cross over configuration. Using an additional single on-off with the multi-function switch does give crossover, but no starter isolation if the engine battery is being used to power the DC panel. When I bought my West Marine battery combiner, the configuration I used in Figure 5 (see attached file) said it was the "best". Back then, I knew so much less and it seemed the "best" way to go.
The last comment I could make in favor of the two multi-function switches is that I don't have to remember if when (or ever) I have a dead bank that before switching the crossover on, I would have to turn off the affected bank's on-off switch. I can just switch either the engine or house designated switch from 1 to 2 and it's done with complete isolation from a dead bank. The only thing I need to remember is to NEVER use the Both position so as to not drain a good battery into a bad one. It just works for me.
i dont like the perko ....1 both 2..... switch at all ...it has to cross both in order to get to the 2 position and to me it takes away your ability to do what you intend to do by crossing the both position this may not be a big deal but it makes me think i am out of controll of my power destiney ...i have a guest 1 both 2 switch that will allow me to go from off to either #1 or #2 by turning the switch clockwise to #2 or counter clockwise to #1 and if i need both i can go there as well but that will be i guess when i have lost my mind
It was after reviewing a number of wiring suggestions and posts that I decided to go with the version Allan implemented with the two 1/2/Both switches. I made sense to me and as Allan pointed out, it only required an additional single under $40 switch. I receive battery isolation during the start cranking via the ACR. Now that I have used it for a bit, I really like what Allan came up with and his reasoning.
My main concerns that I was looking for is 1) Is the battery isolation provided for by the ACR enough? 2) Can the ACR properly charge the sealed battery while receiving a charge on the 6v's? 3) Was something wrong with the connections between the battery and the charger/alternator. 4) I also made a change from what Yanmar/Hunter did. The alternator was connected to the battery bank via the starter. I replaced the 8 or 10 AWG wire (I never measured it) to the starter with 2 AWG to the 1/2/Both switch then on to the battery. 5) If there was anything else I missed.
The switch is a Blue Sea. https://www.bluesea.com/products/9001e/e-Series_Selector_Battery_Switch and yes I need to remember not to go through the Both!
Sorry about the colors. I used Visio and wanted a tool that would show a loop where the wiring crossed on the diagram so there would be no confusion. I will now try to figure out a way to color the "Connectors".
My main concerns that I was looking for is 1) Is the battery isolation provided for by the ACR enough? 2) Can the ACR properly charge the sealed battery while receiving a charge on the 6v's? 3) Was something wrong with the connections between the battery and the charger/alternator. 4) I also made a change from what Yanmar/Hunter did. The alternator was connected to the battery bank via the starter. I replaced the 8 or 10 AWG wire (I never measured it) to the starter with 2 AWG to the 1/2/Both switch then on to the battery. 5) If there was anything else I missed.
The switch is a Blue Sea. https://www.bluesea.com/products/9001e/e-Series_Selector_Battery_Switch and yes I need to remember not to go through the Both!
Sorry about the colors. I used Visio and wanted a tool that would show a loop where the wiring crossed on the diagram so there would be no confusion. I will now try to figure out a way to color the "Connectors".
Yes that is a very out dated way of wiring and very often quite confusing for many boat owners who have it. I have had to address the West Marine "best way" dual 1/2/BOTH switch set up on many boats where the owners were continually doing the wrong thing, even after leaving a legend for how to properly use them.
The scenario where you want to power house loads off start, and need to isolate the engine, is on order of a 0.001% emergency scenario. In fact in all my years of doing this I don't recall an owner ever needing to do that. Could it happen? Sure but a metorite could land on you too...
In a situation like that, in a emergency, I would much rather see both battery switches 100% switched OFF as many boats have wired a high performance alt and all charge sources direct to the house bank so even isolating the start battery does not always isolate the engine from 12V.
The simplest switch configuration for most owners, that still offers isolation of a bad bank and cross over redundancy, is a properly wired dual ON/OFF with a emergency cross connect on the loads side.. The emergency cross connect switch can even be in the form of a Blue Sea ML-500 ACR with remote switch clearly marked for emergency cross connection. In normal use it acts as an ACR, in an emergency it can be used as a cross connect.
As your switch configuration works for you that is all that matters!
I do however urge caution on that set up based on experience. I can tell you from a realistic/real world perspective that switch configuration does not work simply and becomes confusing for most owners (not all but most) I know that have had boats wired with it. Heck the simple 1/2/BOTH is confusing for many too.....
The balance between simple and safe is one that can matter in a emergency situation, especially when an owner starts to panic..I had one owner kill two start batteries in a single summer. He had a dual 1/2/BOTH set up and continually chose the wrong bank for house loads, apparently based on what he was "used to" with his previous boat.......... I made him a laminated legend, labeled the switches very clearly and still, three weeks later, he called and asked me to make the switching easier. I did not ask if he'd murdered another start battery...
You seem to have one redundant wire indicated under the two switches - (the one going from pos 1 on left to pos2 on right.). My only concern with that is that you will still have a +'ve connection to the left buss if only one of the wires is removed.
Thanks twalker. Looking at it the redundant one is the one that runs from the from the terminal block to the #2 on the right switch. I'm not sure I understand your concern. Could you please elaborate. Thanks.. Jon
My concern is that you normally only want power being supplied from one end of a wire, not both ends of a loop. If in the future someone is attempting to troubleshoot a problem they trace the wire supplying power from #1 on the left switch and disconnect it from the terminal block. Normally that would isolate that portion of the circuit from power. In your diagram the circuit would still have power coming from the #2 position on the right switch. (And vice versa)
I would remove the connection from the #1 left switch to #2 right switch and leave the #2 to terminal block. This would still allow emergency cross connect through your switches, provides a redundant wire to the terminal block but eliminates the risk of back feeding power.
I would remove the connection from the #1 left switch to #2 right switch and leave the #2 to terminal block. This would still allow emergency cross connect through your switches, provides a redundant wire to the terminal block but eliminates the risk of back feeding power.
Thanks for clarifying. If I disconnect the wire coming from the "House" battery/post to the #1 post on the left switch, then the only potential source of power would be from the alternator. The #2 on the right switch has no other power source to feed power back to #1 of the left side.... Does that make sense?
I have updated the drawing.
I have updated the drawing.
I updated your drawing for the wire I would eliminate. see attachment to previous post or below.
removing wire from house terminal block to post #1 means you remove house bank + from switch supplying your dc panel unless combined with your start battery. Also means your alternator would be supplying power to your panel but not to any battery unless left switch is set to both.
Not sure if previous attachment is showing properly so here is a different version of it.
Alternatively you could remove the wire from the terminal block to Post #2 on the Right switch. This would eliminate the power loop but would also remove the backup wire from the house bank to the switches.
removing wire from house terminal block to post #1 means you remove house bank + from switch supplying your dc panel unless combined with your start battery. Also means your alternator would be supplying power to your panel but not to any battery unless left switch is set to both.
Not sure if previous attachment is showing properly so here is a different version of it.
Alternatively you could remove the wire from the terminal block to Post #2 on the Right switch. This would eliminate the power loop but would also remove the backup wire from the house bank to the switches.
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Thanks twalker... Actually upon closer examination, I noticed an incorrect depiction of the House to #2. I updated the drawing in my previous post that removed the longer run from the house terminal block to the #2 Starter.
I have uploaded a picture of the battery switch hookup I just finished wiring. This may clear up your previous concern. Please let me know.
Thank you again!
I have uploaded a picture of the battery switch hookup I just finished wiring. This may clear up your previous concern. Please let me know.
Thank you again!
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