Electrical Drawing for Review

[Joe Holmes]

Hello all,

I am about to do a major overhaul of my electrical system and would appreciate any feedback.  Major objectives are to increase house bank capacity, improve safety (fusing), add solar, and improve reliability.  A couple of points:

1.  Following Mainsail's option for 1/2/BOTH/OFF + ON/OFF switches, as described in his article on SBO.com

2.  Not showing any details on wire sizes or fuses (fuse locations shown in blue without detail), still need to work those out.  There is good info available for this.

3.  I do not have a positive bus for any "always on" requirements that bypass the panel.  Would appreciate input on that issue.  I was thinking that at least the bilge pump should connect there.

4.  I have spent a lot of time reading here, especially the recent submission and discussion started by Jon on Della Jean (thanks).  I have shamelessly borrowed where required.

5.  I have not shown details "downstream" of the panel- it does need some clean-up.  Not planning to replace the panel.

6.  I have hull 758, equipped with a voltmeter, no gummy bears.

7.  Converting my 90 amp Leece-Neville alt to external regulation using the kit and instructions from Mainesail.

8.  Solar as shown is tied into the house bank only- with the low amp-hrs used for starting, my thought is that the alt should handle keeping the start battery in a good state of charge. 

As for usage, I am planning some extended cruising over the next year, mostly on the hook.  No air conditioning or heat systems, largest power user will likely be the fridge.  I will have a simple inverter installed, but I am not expecting heavy ac demand.  No microwave, no hair dryer(!!!).  We plan to be in significantly lower latitudes, hence the solar.  I really do NOT want to have a portable generator onboard, for all kinds of reasons. 

Thanks in advance.

Joe

[Stu Jackson]

Joe,

Nice start.

1.  Take the B off the 1-2-B switch, it is not a post on the back of the switch, it is a switch position.

2.  ADD posts on the back of the On Off switch to show where the wires land, like the 1-2-B switch and like Maine Sail's diagrams, which also appear in our 101 Electrical Systems.

3.  Add the house bank voltage sense wiring from the Balmar MC-614 to the house bank.

4.  House bank temp should go to the house bank, not the Charles charger.

[Lance Jones]

That looks good. I agree with Stu's comments.

[Stu Jackson]

Another "general" idea:  as you develop your wiring diagram some more, think of including every single point of connection, much like Jon W did, and as shown in one of the Elec 101 wiring diagrams [http://c34.org/bbs/index.php/topic,6604.msg43692.html#msg43692], and as as you showed for your negative bus bar.  Not all landing spots are fuses.  This will help you immensely when you get to the individual wiring connections "in the field."

[J_Sail]

I strongly recommend leveraging the work done by Jon Windt and Noah on their boats. I have seen both and can testify that they both came out fantastic. Jon did an excellent job of documenting his plans (which were partially based on Noah's) and they have been thoroughly reviewed by various experts. Check out the following links:

Article:
http://www.c34.org/wiki/index.php?title=1987_MK_1_Catalina_34_Electrical_System_Upgrade

19 page-long forum post series of the evolution of Jon's plan:
http://c34.org/bbs/index.php/topic,8708.0.html


Disclaimer: I helped with the paper design as a volunteer E.E. for both Noah's and Jon's so may be a tad biased.

[Jon W]

Hi Joe,
Feedback - The Balmar 614 is missing an inline fuse to the alternator output (comes with the harness), voltage sense wire to the house bank, wire to the ignition switch in the cockpit engine control panel (or oil switch on the engine), and wire to the tach at engine control panel. Will you be adding temp sense wires for the alternator? Is the temp sense wire on the battery charger from the charger to the house bank? Do you have a battery monitor? If you do you should show the shunt. If not you should think about adding one, I've found I use it and the SmartGauge every time I go to the boat. It may be early in your concept, but there are a lot of small gauge wires not shown. Have you decided where you will run the wires?

3) In my case, the battery posts are not very tall and limit making only 2 connections per post securely. This drove an "Always On" busbar, and glad I did it. It is inexpensive, easily fits in the battery compartment, and provides room for future growth. I used it to connect power/fuse for my bilge pumps and battery charger. My future growth is an electric windlass, additional 12V outlets with appropriate fusing, and things I haven't thought of yet.

4) My 19 page thread and the learning in public was painful  , but thought having a complete detail/technical/thoughts discussion in one place would be helpful for the next skipper. So you're doing what I hoped would happen. Borrow away, and glad you're finding it a useful reference. FYI - The write-up in the Tech WIKI is intended to complement the thread with photo's of routing/installation steps, a complete schematic, wire details, and parts list. Intended as a complete work packet of how I did it. Hope it helps as well.

[Joe Holmes]

Thanks very much for the feedback. I will modify my drawing and come back with any questions in the next day or so. 

[mainesail]

Smart Gauge goes direct to house battery terminals, with fuses in positive, not to busbars

Label wire gauges

Label fuse sizes

Alt B- needs to be same GA as B+ do not rely on engine block.

MC-614 B- and V-sense should go direct to house bank (busbars close by are fine)

MC-614 B+ & v-sense need fuses within 7" of house bank

DC Panel Neg Should be as close to house bank as possible

Charger DC neg should be as close to house bank as possible

ACR should be wired for start isolation or use of a start battery for "transient isolation" has been defeated.

Set MC-614 Belt Manager to at least Level 4

Check with Charles to see if you need to bridge unused outputs to the main single output being used. You bridged two but then not to the main output.

It is a best practice to physically stack your high amp main distribution cables on-top of one another on the busbars to minimize voltage drop. For example the short jumper cable cable from house neg gets stacked together on same stud with cable that runs over to engine busbar and start battery neg gets stacked on same stud as that wire. Ancillary loads can be taken off busbar but it is best to physically mate the lugs together on the busbar stud if space allows. Also try to use the middle stud for main runs so ancillary loads pull across a shorter distance. If space doe not allow for enough "fanning" of the main branch lugs so the sit flush on one another place the cables on busbar studs closest to one another.

You only need one negative connection to the engine block, you show two. In a marine application this is best accomplished by directly placing a lug under one of the bolt heads that holds the starter to the engine. Make sure starter case and engine block metals are clean and treated with a electrical grease to minimize corrosion between the aluminum starter ear engine casing.. This results in the least amount of voltage drop to the starter. Alt B- can then go to the busbar.

[Joe Holmes]

OK- this took longer than expected, but I have a revised dwg.  First, thanks to all of you for your comments- this has been a huge help.  I think I took care of all specific recommendations.

Please note the following points:

-Not planning to add a battery monitor other than the Smart Gauge. 
-Wire runs- not yet determined for most- will follow Jon's routing where possible.
-Some of the smaller wires from the voltage regulator do not have the size indicated as they are part of the harness supplied.
-Charles battery charger does not require a bridge on unused outputs and will supply 30A via the single output.  Confirmed with Tech Support.
-The original battery charger has AC power fed from an AC receptacle below the nav station- is it acceptable to set the new charge up the same way? 
-I have added a positive bus, and connected the bilge pump (float switch not shown), and also the 12 V fridge power supply.  I am interested to hear comments on this.  The logic was to be able to switch the panel off, and have the fridge and bilge operate while off the boat.  The fridge can be turned off with the thermostat control.
-I believe I have the ACR in the right configuration for start isolation, using the "normal" settings of "1" and "off" for the two selector switches.
-I will probably add a basic inverter later- likely small and simple.  Is there a recommendation about where to connect this?  Positive bus, with appropriate fusing?  I expect it would have an on/off switch.

Again, thanks for the meaningful feedback. 

Joe

[mark_53]

-I believe I have the ACR in the right configuration for start isolation, using the "normal" settings of "1" and "off" for the two selector switches.

Again, thanks for the meaningful feedback. 

Joe

If your using a Blue Sea ACR, there are 2 other connections not shown. First is the start isolation wire that leads back to the start button. Another is the remote LED. I have lead the remote LED to the engine panel. This provides feedback as to when the start battery is isolated, charging, or locked out due to over or under charging. I have heard of instances where the ACR has either failed or locked out and start battery has failed to start the engine. The LED provides confidence things are working as they should.

[mainesail]

-I believe I have the ACR in the right configuration for start isolation, using the "normal" settings of "1" and "off" for the two selector switches.


Joe

Joe,

If your solar panels or battery charger have the battery voltage to combine level when you start the motor your start bank and house bank are paralleled during the starting, though the relay will drop out pretty quickly if voltage is dragged low enough, but you've not eliminated any chances of a transient. Avoiding transients is what most folks aim for with a dedicated start battery, of course this is an entire discussion on its own.

Start isolation (SI) for the ACR is a 12V trigger from the start button that drops the relay out during cranking to provide true isolation between start and house banks during the starting process.. With a 1/2/BOTH switch SI is not necessary but with a 1/2/BOTH + ON/OFF, if you desire truly isolated starting, you need to run the SI circuit.

[Jon W]

What does SI stand for?

[Noah]

Start Isolation.

[Joe Holmes]

Modified ACR to include the start wire.  I will not install the remote LED for now.

Now working on a cable list with connector details, planning routing etc.  This process has actually turned out to be more satisfying than I originally anticipated, thanks again to all of you.

Joe

[Footloose]

I recently did similar modifications but used an Echo Charger instead of an ACR.  My thought was that this separated the banks instead of paralleling them when charging.  What was your reasoning for using the ACR as opposed to an Echo Charger?  Not being critical, just trying to learn.