Review my re-wire plans Please

[mikeo16]

Hi, attached is a diagram for re-wiring my 1986 Catalina 36. Any and all input would be greatly appreciated. Here are a few key points I considered:

1. I have had the same boat for over 20 years and have continued to add to the basic 80's setup
2. I am comfortable switching to both when running the engine and then switch back to house (#1) when anchoring out. I evaluated adding a blue seas ACR but do not see the need
3. I am adding refrigeration which is causing me add a 3rd battery and solar
4. original wiring is undersized so upgrading from 4 guage to 2/0 guage to batteries

[smac999]

what is the bottom diagram?

looks like a simple system. if you are happy with always moving the switch.

I would not run 2 different panels through a single controller. get 2 controllers.
controller should be fused at charge bus. bilge pump should be charged at charge bus.

2/0 from switch to panel is likely ridiculous for that boat. and likely not going to be able to connect it at panel end.

generally the anchor comes off the switch as well.

[mikeo16]

Thanks for your reply! The bottom diagram was in error - I used that as a model to get ideas and should not have included.
Good point on one Solar charge controller for each panel - with the price coming down so much now it is not a big deal. I was thinking on starting with just the single rigid panel (160 watts) to start and then evaluate how much additional I need after first season. Since I will have 1 MPPT controller for each panel, I have updated the diagram to reflect a smaller model (75/15) which I think will be more appropriately sized.
Good feedback on the switch to panel wire size - I have changed that to now reflect size 8 gauge wire - is that more appropriate or should I go a little larger?
For the anchor windlass connection point, I was concerned with the power demand. I installed that last year with the 2/0 wire due to the long run of about 55 feet round trip. I have been using the Maxwell 135A circuit breaker as a on/off switch. If I were re-route 2/0 to the main DC panel switch, wouldn't I then need a larger gauge wire to the DC Panel Switch?
Any comment on the 300A fuses on the Battery - is that the appropriate size?

Revised diagram attached - I really appreciate a second set of eyes to provide insight - thanks

[moctrams]

Good start. Here is what I did to my 1982 Cape Dory.

[Emouchet]

What I like with the Si-ACR is that it does everything automatically. This little robot is removing the hassle of always remembering to switch in between 1, 2 and 1+2.
I can easily be distracted and forgot.
I now have 2 switches, Service ON/OFF, Engine ON/OFF.
Keep it simple.

[stormalong]

Originally Posted by Emouchet

What I like with the Si-ACR is that it does everything automatically. This little robot is removing the hassle of always remembering to switch in between 1, 2 and 1+2.
I can easily be distracted and forgot.
I now have 2 switches, Service ON/OFF, Engine ON/OFF.
Keep it simple.

I agree entirely. A Yandina or similar voltage controlled charging relay makes life much easier. Anytime there is a charging voltage on either battery bank the two banks will be joined and charged. Take away the charge and they will separate. The only caveat is that all batteries should be the same type flooded lead acid, gel or whatever.

[TreblePlink]

Just one bilge pump?

[seabreez]

Originally Posted by mikeo16

Hi, attached is a diagram for re-wiring my 1986 Catalina 36. Any and all input would be greatly appreciated. Here are a few key points I considered:

1. I have had the same boat for over 20 years and have continued to add to the basic 80's setup
2. I am comfortable switching to both when running the engine and then switch back to house (#1) when anchoring out. I evaluated adding a blue seas ACR but do not see the need
3. I am adding refrigeration which is causing me add a 3rd battery and solar
4. original wiring is undersized so upgrading from 4 guage to 2/0 guage to batteries

I reviewed your drawing and here are my comments. All wiring should be marine American Wire Gauge (AWG) thinned gauge wire to prevent corrosion and all connections should be crimped and then covered with heat shrink. Also you indicate that you will upgrade your gauge of wire from 4 to 2/0. There is a huge difference from a #2 AWG wire gauge and a 2/0 wire. Most ground bonding wires to ground should be #2 awg wire, all battery cables, you can leave with 2/0 (expensive) for your start batteries, you should verify your starter draw current (in your engine manual) and multiply this by 1.5. The 2/0 wire from your selector switch to your control panel is excessive a #2AWG is more than you need. The alternator wires are also very big; the ground a #2 is plenty good and a #8 awg is acceptable for the red power terminal to the starter or battery. I am currently rewiring a tugboat and have calculated much of the wiring and the fuses sizes and the wiring size. Also all you bonding wire should be of yellow to prevent you from mistaking your black wire for positive on ac circuits. That is a written recommendation from ABYC and the wire gauge charts in Blue Sea catalogs. You can consult the Blue Sea catalog and their wire charts and amperage for the size of wire... anyway... my 2 cents worth... Roger

[Tikka]

just from my expirience , regardles how many solar panels you have, all should be connected parallel . use one smart controller rated to cover amperages.
reason been , they chasing each other, making charging mess, unless you have completely independent systems.
Solar - controller - fridge battery.

[smac999]

the 2/0 alt wire is huge. will be hard to connect. and the weight will be a lot of force hanging on the alt studs. 4awg would be good.

[mitiempo]

Originally Posted by Emouchet

What I like with the Si-ACR is that it does everything automatically. This little robot is removing the hassle of always remembering to switch in between 1, 2 and 1+2.
I can easily be distracted and forgot.
I now have 2 switches, Service ON/OFF, Engine ON/OFF.
Keep it simple.

I agree with this as well. Also an ACR will allow the solar to keep the start battery charged without any switching.

[mitiempo]

Originally Posted by seabreez

........Also all you bonding wire should be of yellow to prevent you from mistaking your black wire for positive on ac circuits. That is a written recommendation from ABYC........

Bonding wiring (which is not shown in the op's diagram) is typically green. DC negative should be yellow if it is a complete re-wire - if it isn't a total re-wire there is no logic in adding a third DC color.

[Leakie Marine]

+1 on the VSR/ACR, I would also have the bilge pump fuse at the bus end of the cable to protect the wire.