Request for a schematic review

[Last Call]

Good Morning,

If you see any areas of concern I would appreciate any input. I am new to DC wiring and sailboat wiring as well.

Thanks Bob.

[Last Call]

The image quality is bad click on the image when it opens you can right click it then open it in a new tab then zoom in from there . I dont know how else to post it.

[djmarchand]

Bob:

It is very, very difficult to read your schematic with its green on black background. Can you post it as a black on white image and maybe at higher resolution as well. Also it would help to label more of you components, like what I assume is the batteries but they aren't labeled start or house or ?

David

[Last Call]

Here is a little better attachment . I am limited by the file attachment restrictions of this forum . The file is a vector cad file converted to a JPG using MS paint.

[SteveSails]

Hello Bob,

Stared at your schematic for awhile and I think I got it. I'll break it down as follows.

Assumptions:
Green lines negative and red is positive
No engine so no starter motor or alternator wiring
Propane gen set has no starter motor, is it a pull start like a Honda 2000?
There are 4 batteries in two banks, 2 batteries in parallel in each bank, 12 volts each
Switch S1 for shore power or Gen Set is actually AC wiring to the inverter/charger unit
Switches do not switch neg wire even though that is implied by your schematic
Numbers in blocks on the right are amp ratings of circuit breakers

Comments
Overly complex for what you are trying to accomplish, consider one battery bank and one battery monitor. Amp hour capacity depends on the load AND your ability to recharge to 100%, charger capacity should be at least 20% of the battery bank amp hour rating.
Not sure of your solar charge control wiring. Solar charge controllers can be connected directly, through a fuse or breaker, to the battery bank.
To help make things clearer try redrawing with charge sources on the left, battery bank center and loads on the right. This will show the energy path, energy in (charge sources), energy storage (battery), and energy out (loads). Also take a look at the Blue Seas web site, lots of good info there on DC wiring.

Hope this helps,
Steve (retired electronics engineer)

[Richard_W]

One thing you might want to add is galvanic isolator or isolating transformer somewhere on shore AC line before S1. I assume shore and genset lines, and S1 are unmarked AC circuits.

[goboatingnow]

Just be aware that as draw the charge source wires are in effect paralleling the two banks thereby In effect creating one bank with a safety hazard in that major battery currents can flow through wires not designed to withstand them.

This needs diode isolators

Agree with previous no point in dual banks

Combine , better for the batteries, Better effective capacity and lower cost

Fuse all battery feeds

What is the purpose of S2. It serves no purpose all charge sources should have the battery in circuit



Dave

[Dsanduril]

Not enough detail on the solar charge controller to tell if it has isolated outputs, but not drawn that way. The way it is drawn the charging wires from the solar controller permanently combine house banks 1 and 2 in parallel, so having S3 to separate/select them doesn't do anything.

[djmarchand]

I can now see the schematic, thanks. Almost everything has been said. A couple of observations:

I don't understand what a PM3 Series Convert/Charger is. If it is a shore power inverter/charger then why is the second?? solar controller's output being fed into a third??? input to the inverter/charger.

Switch panel 2 is confusing. It looks like both 120 V AC loads (the air conditioner) and 12 V loads (the windless and others) are being supplied from it, and all from the same DC source?

And in any case be careful about your fuse/breaker sizing. A 15 amp fuse needs 14 gauge or bigger wire connected to it and all other downstream circuits. 20 amp needs 12 gauge and 30 amp needs 10 gauge. So for example are you going to wire your 12 V (or is it 120V) wireless router with 10 gauge?

With all due respect I recommend that you find a friendly marine electrician that will let you do all of the dog work: running wires and mounting components and let him check over the schematic and do the terminations.

David

[Last Call]

Originally Posted by SteveSails

Hello Bob,

Stared at your schematic for awhile and I think I got it. I'll break it down as follows.

Assumptions:
Green lines negative and red is positive
No engine so no starter motor or alternator wiring
Propane gen set has no starter motor, is it a pull start like a Honda 2000?
There are 4 batteries in two banks, 2 batteries in parallel in each bank, 12 volts each
Switch S1 for shore power or Gen Set is actually AC wiring to the inverter/charger unit
Switches do not switch neg wire even though that is implied by your schematic
Numbers in blocks on the right are amp ratings of circuit breakers

Comments
Overly complex for what you are trying to accomplish, consider one battery bank and one battery monitor. Amp hour capacity depends on the load AND your ability to recharge to 100%, charger capacity should be at least 20% of the battery bank amp hour rating.
Not sure of your solar charge control wiring. Solar charge controllers can be connected directly, through a fuse or breaker, to the battery bank.
To help make things clearer try redrawing with charge sources on the left, battery bank center and loads on the right. This will show the energy path, energy in (charge sources), energy storage (battery), and energy out (loads). Also take a look at the Blue Seas web site, lots of good info there on DC wiring.

Hope this helps,
Steve (retired electronics engineer)

Thanks You, all your assumptions are correct. I will draw it up again. The reason for multiple banks was based on my assumption that a battery bank should be isolated from loads while charging. I am taking from your reply that this is not the case. That does simplifies things a bit.

Question:
I want a solar panel and the charger thats onboard the converter. May I run both the solar charger and the converters on board charger directly to the battery? They both have controllers built in. I am concerned that one might damage the other some how or perhaps fool the 2 different controllers ability to determine the state of the bank or back feeding the solar panel.

I will have better information to use once all the components have been delivered.

Thanks Bob

[Dsanduril]

Originally Posted by Last Call

...The reason for multiple banks was based on my assumption that a battery bank should be isolated from loads while charging. I am taking from your reply that this is not the case. That does simplifies things a bit.
...

Actually, just the opposite, when you charge a battery and then take it back out you only get about 85% efficiency, the rest goes to heating the battery, wires, etc. Best to run your systems while the charger is on. This will reduce the amount going into the batteries (by the amount being used by the systems) but you will get 100% efficiency from the charger terminals to the device terminals.

With solar, it's good to schedule power usage while the solar is operating; it's raises the voltage (most things like that) and saves the battery round trip. For instance, if you have an electric watermaker or fridge using those the most while the sun is charging will reduce your losses to battery inefficiency. Batteries should be the last resort.

[SteveSails]

Bob,

Yes, you can connect both the solar charge controller and the charger (converter?) to the battery bank at the same time. The circuitry in the controllers will prevent back feeding to the solar panels or damage to the controllers. Just make sure you have the appropriate size fuse or breaker in the wiring of each charge source.
I also noticed a 30 Amp breaker labeled 'Air Conditioning', do you intend to run air cond off the battery bank? If so you may want to rethink that, the amp hour draw will quickly drain a moderate size bank.

I think the recommendation of working with a marine electrician for this project is a good one.

Steve

[Sandero]

I've noticed several sailors have created wiring diagrams for comment. I suppose this is a good idea. I wonder are these created before the wiring has been done or are they documenting what's been installed?

I have 8 wiring diagrams for Shiva... not actually industry standard schematics using symbols and protocols. They are:

12 volt power distribution
engine wiring
house (panel) distribution
NMEA wiring (nav instrument 0183 network)
nav instruments (data and power connections)
Link Monitor wiring
Splice at mast base
110v power distribution

On some diagrams I include the gage and color of the wire. And I've tried to label wires in the boat but that's an ongoing project. It's a real nightmare to try to understand a mess or even a neat network of hundreds of wires without diagrams and labels.

And as tempting as it is to leave old wires I think pulling them out is the way to go.

Boats and the electrical needs of sailors are so different it's hard to imagine that two would have the same wiring and equipment.

Steve.... have a look at my madness... is it too complex... I don't know how to include all the stuff in a less complex way!

[Last Call]

[comments:
Attached is a revision on the drawing you looked at for me . My appologoies for the lack of proper symbols.
I have the bilge pumps and a low amp ventilation fans directly to the battery each fused.
The solar panel is directly on the battery. It has a built in control circuit.
Fuse ratings shown are not accurate just place holding txt blocks.


Questions
Is a 100 watt 30 amp solar panel enough to charge 4 parallel 100 amp hour batteries?
Do I need a switch to isolate the chargers from one another? (Solar panel and charger/powersupply)
Would it be better to break up one of the busses so that a section is hot all the time and hook my fan and bilge pumps in there?
Should I base my fuse values for dedicated circuits on the wire ratings or the devices maximum load ?
Do you think its over kill on the number of batteries given the devices shown ?

QUOTE=SteveSails;1443613]Hello Bob,

Stared at your schematic for awhile and I think I got it. I'll break it down as follows.

Assumptions:
Green lines negative and red is positive
No engine so no starter motor or alternator wiring
Propane gen set has no starter motor, is it a pull start like a Honda 2000?
There are 4 batteries in two banks, 2 batteries in parallel in each bank, 12 volts each
Switch S1 for shore power or Gen Set is actually AC wiring to the inverter/charger unit
Switches do not switch neg wire even though that is implied by your schematic
Numbers in blocks on the right are amp ratings of circuit breakers

Comments
Overly complex for what you are trying to accomplish, consider one battery bank and one battery monitor. Amp hour capacity depends on the load AND your ability to recharge to 100%, charger capacity should be at least 20% of the battery bank amp hour rating.
Not sure of your solar charge control wiring. Solar charge controllers can be connected directly, through a fuse or breaker, to the battery bank.
To help make things clearer try redrawing with charge sources on the left, battery bank center and loads on the right. This will show the energy path, energy in (charge sources), energy storage (battery), and energy out (loads). Also take a look at the Blue Seas web site, lots of good info there on DC wiring.

Hope this helps,
Steve (retired electronics engineer)[/QUOTE]

[SteveSails]

The drawings from Sandero are a work of art and show the amount of effort required to produce detailed drawings. My only comment would be to have the instrument wiring on a separate page so it doesn't clutter the DC distribution diagram.

Bob, A 100W solar panel is not going to provide 30A, more like 8A with optimal conditions and using an MPPT controller. You may be looking at the maximum amperage your controller is rated for, you would need over 350W of panels to get close to 30A. Use Watts = Amps x Volts to figure it out.
Fuses and breakers protect the wiring from being overloaded, for example the maximum size breaker for a #14 wire would be 15 Amps. Get a copy of Nigel Calder's Boat owners Mechanical and Electrical manual and all will be explained.
I don't see the need for the AC to DC converter as drawn, just use the battery charger when AC power is available. As for the AC wiring the best I can say is read Nigel Calders book then start over.

Steve