Re-wire the boat

[Tangles]

an older thread with some knowledgeable blokes had this diagram of re wiring a boat… it might be of help

[brett62]

Brett, just a question, my auto trim tabs each have a 15 amp fuse for each actuator and a 30 amp for the power supply to the control box, noticed you had only a 5 amp for yours. Is this too small or even needed.

Dignity you are correct. There is a main fuse at the transom for the pump and then fuses for each tab on the switch panel and then there is 2 x 1 amp fuses from the auto control box. I don't have the wiring diagram with me for the bennet tabs. I will down load and add to the diagram. The wiring down the back is something else and hard to understand what is going where for what. Thanks for the pick up.

[brett62]

Hi Brett,

there are issues with a bypass of the shunt and you have a few switches/breakers that are really just adding points of failure and can be done away with mate. If you are happy to wait until next week, pm me a phone number, and once I'm home from work I will give you a ring.

Regards

Scott

Thanks Scott

I am away at work at present also and return home on the 28th. I will PM my number to you.

I will keep working on the diagram at lest it will show what other equipment that will be wired.

There is no hurry as it will be some time before I start the re-wire just want to get the plan completed so I know what I need to purchase as its the next job on the list once the motor is removed.

[brett62]

Well it's time to start the re-wire and looking at the date when I started the post makes me wonder where the time has gone.

Anyway I have attached a high level drawing of the main runs I am looking to do and after some advice/comments.

boat.jpg

[scottar]

Only a couple of things there Brett. The VSR will be costantly monitoring and thus drawing power. If the boat is layed up without a chargter it could glatten the start battery unless it's run via the start isolator. Only thing is your house battery monitor. As is it will only be good for voltage. If you want current and hence capacity all the negatives (in and out ) for the house bank have to run through it. I have seen on one occasion that this caused charging issues - never got tobsort out why though. The system just got bypassed.

[brett62]

boat rev1.jpg

Thanks Scott.

Here is rev 1 showing removed switch from the VSR circuit and the negatives are now all going to the house bank negative buss after the shunt. In saying that I still have the negative from the house and start bank connected direct. Should I also connect this to the negative buss ? Having both banks connected via the negative may cause some wrong reading from the battery monitor may-be ? should I have a switch ?

All the fuses in these main runs will be manual reset breakers so the breakers either side of the VSR will be left open and closed only if the the DC-DC charging system fails.

All breakers will be less than 300mm from battery and switches in a dry area unlike the original set up. The inverter will be directly wired to the shore power inlet as it senses power input from the shore connection and shuts down into monitor mode.

I will start working out wire and breaker sizes next and update the drawing if you wouldn't mind checking that also.

[chocolatemoose]

FYI. have a 240v marine tech issue a safety notice for your 240 safety switches etc for insurance purposes
Are you going to use a pre made up dual bank battery cluster? or run 3 switches + vsr seperatly?

[brett62]

FYI. have a 240v marine tech issue a safety notice for your 240 safety switches etc for insurance purposes
Are you going to use a pre made up dual bank battery cluster? or run 3 switches + vsr seperatly?

Hi moose,

I will have 3 switches.

As to the 240 volt system, I hope it wasn't a marine tech who did the wiring on this system as the parts used and installation was completely sh*t and the best part was the shore power inlet module had no cover on the back and you could very easily make contact with these connections. Thanks for the heads up moose and I have a gent lined up to do the checking on the 240 volt side.

[scottar]

Thanks Scott.

Here is rev 1 showing removed switch from the VSR circuit and the negatives are now all going to the house bank negative buss after the shunt. In saying that I still have the negative from the house and start bank connected direct. Should I also connect this to the negative buss ? Having both banks connected via the negative may cause some wrong reading from the battery monitor may-be ? should I have a switch ?

All the fuses in these main runs will be manual reset breakers so the breakers either side of the VSR will be left open and closed only if the the DC-DC charging system fails.

All breakers will be less than 300mm from battery and switches in a dry area unlike the original set up. The inverter will be directly wired to the shore power inlet as it senses power input from the shore connection and shuts down into monitor mode.

I will start working out wire and breaker sizes next and update the drawing if you wouldn't mind checking that also.

Yes it will. For the battery management system to calculate capacity remaining accurately, all current that flows in and out of the house bank must pass through the shunt. The issue I saw previously, I suspect was caused by the negative for the VSR being connected to the wrong side of the shunt which created just enough voltage drop to stop the VSR ever switching in - theory only though as I never got to go back to have more of a look. We bypassed the shunt and everything charged as it should have - and we went fishing. It still read voltage accurately but gave no current readings at all. For capacity / current to be accurate. the only thing that can be connected to the negative of the house bank is the shunt and then everything else to the other side. You will need to confirm that the shunt is capable of handling the large currents drawn by your inverter though. All good with the breakers and wiring.

[brett62]

I have now placed a isolation switch on the negative side between the house and crank batteries so that takes care of that issue Scott.

I have started adding wire and fuse sizes now and you can see that the shunt is 500A/50mv. The inverter recommended fuse size is 250 amp so this should be ok?

Scott the original wiring for the battery monitor is completely different to what you have pointed out and it would be obvious that whatever the reading were before they would have been completely wrong.

boat rev2.jpg

[Brother Sharkbait]

Hi
Just wondering what program you are using for your schematics?
Cheers


Sent from my iPad using Ausfish forums

[brett62]

Hi
Just wondering what program you are using for your schematics?
Cheers


Sent from my iPad using Ausfish forums

I am using TinyCad

[chocolatemoose]

out of interest. you have 240v inlet going to an inverter, but not the 240v battery charger?

[brett62]

Moose now added and I have also changed the VSR around and have it wired to the battery isolation switches and the common connected to the house bank after the shunt. I think that is how it should be ?

The cutting of the dash is soon to start Moose so watch this space !!!!!!!!!

boat rev3.jpg

[chocolatemoose]

Are you having gpo's inside the boat? at the kitchen or for fans, or bathroom etc?