Single Circuit Battery ON/OFF Switch

Hart · Post by **Hart** » Thu Sep 20, 2012 10:02 pm

My two-battery switching system has three switches, that I suspect are common to most of our Trojans (that have dual batteries, any way):

1. Port ON/OFF
2. Starboard ON/OFF
3. Master 1/2/ALL/OFF

I believe that my original, stock Sudbury ON/OFF battery switch is bad on the port side. If I isolate that one to "ON" and put the Master to "ALL" or "1", I get no juice.

I'm a sub-moron when it comes to electrical, but I've researched and, having come up empty on getting a replacement Sudbury, I have zeroed in on the following potential replacements:

http://www.amazon.com/Perko-9601DP-Mari ... m_sbs_sg_4

http://www.boatersworld.com/product/MP80809921.htm

http://www.wholesalemarine.com/pc/BSS-9 ... witch.html

http://www.boatersworld.com/product/MP63514875.htm

Am I in the ballpark with these? If so, is one preferable (last one is pricey, and I haven't scrutinized specs to determine why)? If not, are there any suggestions?

Or, ideally, does anyone have a line on an original Sudbury?

Big D · Post by **Big D** » Fri Sep 21, 2012 9:59 pm

I prefer the Blue Sea switches. They are well built. The difference in price is because the last one is rated for 600 amp continuous, the other is 350 amp continuous.

Hart · Post by **Hart** » Sun Sep 23, 2012 11:12 am

Big D wrote:I prefer the Blue Sea switches. They are well built. The difference in price is because the last one is rated for 600 amp continuous, the other is 350 amp continuous.

I appreciate that reply.

So, the switches I'm looking at are the correct ones to replace with?

Big D · Post by **Big D** » Sun Sep 23, 2012 4:51 pm

I don't have those old switches on board mine but if you're sure they are ON/OFF switches, then the Blue Sea samples you posted will work. No sense putting bad connections on new switches so make sure the cable ends and connectors are in good shape. If the cable insulation seems discoloured or brittle, cut it back until you see good wire and install new lugs. Installing glue impregnated heat shrink tubing helps fight off corrosion.

aweimer · Post by **aweimer** » Sun Sep 23, 2012 7:00 pm

My 1975 Tri-Cabin has no switches as all. My port engine has an extra wire on the starter that is the 12v wire for the boat. This engine start battery is the house battery too and is backed up by a secondary selenoid that lets me start the port engine with the starboard battery.

Up front I have one battery for the genny.

Based on the manual i purchased with the 12v diagram this was wired this way with no switches at all. I like the simplicity.