Thread Tools Display Modes
Old 05-30-2013, 12:26 PM   #1
City: Chestertown, md
Country: united states
Vessel Name: Socially Sea Cured
Vessel Model: 1989 44' Heritage East Sundeck
Join Date: Feb 2013
Posts: 16
Rotary Switch replacement

I am new to this forum and finally made the jump to a trawler after many years of dreaming about it. I have just bought a boat with, I believe, a bad transfer switch for incoming power. Presently both AC circuits will work on shore power at both AC circuit panels but not when set to generator. The generator is putting out 118 volts at the generator and there is 117.9 incoming at the transfer switch #1 (house panel switch). The air conditioning panel is only energized by shore power at this time. I would like to have two new switches in the lines so that the 2000Watt inverter, the 8 K generator, or a 30 Amp shore power cord can power the house panel and a 30 Amp shore cord or the 8K generator could power the Air Conditioning panel. Since the 8k Genny should be about 66 amps I will have to install a bus bar to split it into two 30 Amp lines through circuit breakers and then feed these lines into the rotary switch. I am not sure if the Inverter has to go through the transfer switch as it will automatically switch to inverter when AC power is interrupted and back to AC when it is restored, but I have had an automatic switch start a fire in my last boat so I thought it prudent. If it could be wired directly into the panel that could change the switch configuration I am looking for simplicity but also for safe operation.
Power inputs;
Two Standard 30 Amp Shore Cords, circuit breaker on dock end
Westerbeke 8 K BT Generator Will install circuit breaker before rotary switch to split into separate thirty amp lines
Heart Interface Freedom 20 Inverter with auto switching between incoming AC & DC power
Thanks, John

jtbedell is offline   Reply With Quote
Old 05-31-2013, 05:34 AM   #2
FF's Avatar
Join Date: Oct 2007
Posts: 14,908
Sounds fine as a system.Just buy and install the rotary switches.

Our method is far simpler in we have plugs that is the boat and sockets that are the ends of shore or noisemaker power.

Simply move the plug to the desired source

.Simple cheap and if handy less work to do and a snap to trouble shoot.

FF is offline   Reply With Quote
Old 05-31-2013, 07:28 AM   #3
Senior Member
City: Green Cove Springs, Florida
Country: USA
Join Date: Feb 2012
Posts: 179
Send a message via Skype™ to bglad
Your generator should have breaker on it or near its location. Keep it wired straight 120 and connect it directly to the rotary switch with jumpers between the two panel 120 volt legs. If you split its output you will have to balance each leg to fully utilize its output. Inverter can be connected between rotary switch and house panel (not AC panel) if it is rated for enough current so it will take over if power fails. I can comment better from my desk top. Smart phone typing is onerous...
bglad is offline   Reply With Quote
Old 05-31-2013, 10:02 AM   #4
FF's Avatar
Join Date: Oct 2007
Posts: 14,908
If you are doing all this why not purchase the rotary SW large enough to eventually handle an upgrade to 240V 50A shore power.

Plug & socket would not need an upgrade 240/50 std.
FF is offline   Reply With Quote
Old 05-31-2013, 10:12 AM   #5
Senior Member
City: Hampton Bays, N.Y.
Country: USA
Vessel Name: Grand Yankee
Vessel Model: 1981 49' Grand Banks Classic
Join Date: Oct 2007
Posts: 275
Hi, I have a Tech who live by you named Dan Fleming. He has done a lot of work for me with his son Mark. ABYC certified. 410 220 5327. Lives on Pine Tree Rd. in Chestertown. Good Luck.
Ron T is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

All times are GMT -5. The time now is 06:18 AM.

Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012