Blue Sea 2 Source Lockout

[watson1987]

I'm looking to wire my hot water tank to my inverter, so I have the option when on the hook for 2-3 days.

I need to ensure that both shore power and inverter cannot power the hot water tank at the same time. Having two breakers, with sources from both those sources and the load sides going to the water tank but does not provide the safety of both sources at once. I'd prefer to have the extra switch, so I have to purposely switch it on, and not have to forget to turn it off when I switch to the inverter during day-to-day operations.

I have an R31 with a Blue Sea 360 series panel. Some panels offer lockouts, but I can't find just those breakers sold separately for the 360 panel. My other option is to use an automatic transfer switch behind the panel to ensure both AC sources can't make it to the panel simultaneously.

https://www.bluesea.com/products/catego ... out_Slides

https://xantrex.com/products/accessorie ... fer-relay/

Has everyone else who has wired this up, just put it just wired to the inverter side, and skipped the pass-through AC source from the main shore panel?

 

[watson1987]

Maybe the solution for the 360 panel is to get one of these

https://www.bluesea.com/products/1481/1 ... _2_Sources

I need to see how many unused breakers I have today, as this, plus the existing breaker is going to take up quite a bit of space.

 

[dbsea]

It takes approximately 90 minutes to heat the water in the 11 gallon hot water tank from cold to 167 degrees while on AC power. I think you'd be disappointed with how that left your house bank condition if you powered your hot water heater in this way, given it uses 750w at 115V. IMO, its much more effective to run your engine at 800RPM for 60 minutes in throttle only mode which will accomplish the task of heating your hot water heater with the heat exchanger, and will also boost your batteries with the alternator, all while only using .5 gallons of diesel...

caveat: Since you have lithium, maybe this is irrelevant. 🙂

 

[watson1987]

Given the water already stays warm enough for 24-36 hours, I suspect I won't use all that much to sustain the tank for 36-72 hours, which would be the upper end of what my anchorages last.

And yes, having lithium means I already have excess energy today. I've left a 3-night anchorage with 70% of my 400Ah capacity with the stock 150W solar. I should have my new 300W solar system done this week (sun permitting for the installation - pun intended), and I should be neutral or positive in the future. I don't mind dumping 100Ah of juice into the water tank.

 

[watson1987]

For future reference, if anyone else is interested in doing this. Here is the photo of the automatic transfer switch

https://imgur.com/a/O9mAcp5

I used the mid-berth outlet breaker (15amp-inverter) for the hot water tank and the existing (20amp-shore) hot water tank breaker. I jumpered the front and mid-berth to be on the same breaker (15amp) and left the galley alone. The odds of me using 15amps between both berths is unlikely, but I could see the need to have a kitchen appliance still in the galley.

The setup is pretty straightforward once you understand that shore power comes to the AC breaker panel inside the pilot house, then back to the inverter, and then back to the pilot house breaker panel. The top half of the breaker panel is all shore power, and the bottom half is all run through the inverter. The inverter will eventually go into bypass mode, but the power is still transitioning back and forth. Wiring the automatic transfer switch involves matching wires colors, be sure to remove the neutral line for the hot water tank of the one bus bar and wire it just to the neutral on the load side of the transfer switch. Grounds can be shared between the inverter and shore power, and the live wires will feed off both breakers and into the respective inputs on the transfer switch. There are 2 neutral bus bars, one for the inverter and one for the shore. Make sure these match up with which side of the transfer switch your live wire is coming from.

I was reading 6.75amps @ 120V, which is about 800W when the tank is running.