2GM20 Alt/Starter Wiring

[APWTryfan]

Good*Day!
I have new to me C&C33 mII with 2GM20 and am adding solar with battery*upgrade.
I want to run*alternator to house bank*with*ACR*to start battery. Solar and AC charger will also*run to house.

The current Alt/Starter*runs via a single wire to common post on Off-1-All-2 switch.

I*would like to run Alt to battery and Starter to*switch.*

Q1*- is it possible to separate Alt/Start wires and if so, is there anything*in particular I should be looking out for with 2GM20?

Q2 - House bank will be 2 x AGM G31 220AH total in*parallel. Is there any risk with current alternator (sorry do not know the*make) charging these new AGM's?

Thanks!

Andy

*

[Stu Jackson]

1 OEM 1-2-B Switch Wiring History Alternator/Batteries & "The Basic" 1-2-B Switch BEST Wiring Diagrams


2 Hitachi Alternators 101 http://forums.catalina.sailboatowner...d.php?t=166123 This comes up so often on other boating forums...

[APWTryfan]

Originally Posted by Stu Jackson

1 OEM 1-2-B Switch Wiring History Alternator/Batteries & "The Basic" 1-2-B Switch BEST Wiring Diagrams


2 Hitachi Alternators 101 http://forums.catalina.sailboatowner...d.php?t=166123 This comes up so often on other boating forums...

Hi Stu thanks for all your help! I have poured over all the material you have provided here and on other forums.

My scenario is where the starter and alternator are connected via single wire to common post on switch.

I have 2 house and will soon add a separate 3rd start/reserve battery.

If I leave the alt/start connection on common post of Off-1-All-2 switch and always leave switch on 1 (house and start), my new 3rd battery would function only as an emergency reserve. The only disadvantage is the risk associated with switch turned to Off position while running engine.

I would keep 3rd reserve battery charged with ACR.

My immediate goal and impetus for this project is installation of 200W solar wired directly to house. Time is ticking as we head out soon and need to get solar up and running ASAP while minimizing work and impact to existing system.

Do you see any other disadvantages with this scenario?

I will also consider exchanging my 2 x 12V G31 AGM's with FLA to avoid any potential charging issues from ALT but will research more.

Thanks again!

Andy

[APWTryfan]

Another post on this forum has answered my question - voltage spikes from starting with a "shared" bank can damage electronics.

2 weeks ago I would never have thought I would be speaking this new language - I'm a learnin'!