R-25 Inverter install

[gerlots]

Trying to find the right spot to mount a new 1800w inverter. Near the batteries would be best, but I have no idea how to run AC wires to the AC panel. Is there a trick to accessing the wire ways or do I have to run them exposed? Maybe a mouse tied with a string would help. :? Any ideas?

 

[knotflying]

I have not installed an inverter, but my assumption is that you don't necessarily need to run anything to your panel. You would need to intercept the lead from shore power and hook everything up from there somewhere along the line. Ideally this would be somewhere in one of the cockpit lockers. You will probably need to run a line for a remote switch for the inverter control or like my pro-mariner there is an option for the switch to be mounted right on the unit.

 

[Favunclerich]

I have an 1800W inverter in my R-25 that was installed by the previous owner. It's mounted on the lower aft wall of the cave and wired to the generator switch on the AC panel. The AC wire goes aft from the inverter, across the stern of the boat, and then it was fished forward in the gap between the hull and the starboard side hull liner. The inverter is connected to the house batteries using heavy cables and a switch similar to that used for the thruster battery on/off. The inverter manual has instructions for how to size these cables as a function of their length. It's a very clean installation and I would be happy to provide more details if you email me at richodendahl@yahoo.com.

That said, I would add that an 1800W inverter is overkill for my style of cruising. I only use it to charge cellphones, laptop, Ipad and my Torqueedo. Together they draw much less than 100 watts. The large 1800w unit has significant energy loss due to its size. The manual shows that it is 80-90% efficient depending on current draw, even less efficient at lower output levels. I would be much better off with a smaller, lighter unit. I don't let my wife use her small, 1200w hairdryer at anchor because the house battery bank is inadequate. I have two AGM batteries at 105 Amp-hours each. Her hairdryer would draw close to 100 amps plus the transformer losses. Even a small microwave would draw similar current. While 15 minutes of hair drying would "only" theoretically consume a quarter of a battery, it's important to understand that battery amp-hour ratings are based on drawing it down over 20 hours (about 5 amps per battery). A draw of 100 amps would drain the battery bank much faster than two hours. Some tug owners have added extra batteries. The following statement is from the Xantrex owner's manual "Xantrex recommends a minimum battery size of 200 Ah for moderate loads (less than 1000 W) and greater than 400 Ah for heavy loads." So if you really need an 1800w inverter for your style of cruising, you should probably also upgrade your house battery bank.

Best regards,
Rich

Before

 

[gerlots]

I have upgraded the house Batteries by adding two additional batteries. This gives me 440ah. I have also included a 155w solar panel to keep up with some of the consumption. Our style of boating is mostly away from marina docks.
My shore power connection is Stbd. side forward, adjacent to the electrical cubby hole.
I hate to tie into the DC panel feed from the batteries as I am not sure of the wire size is large enough. So with that said I have to find a route from the panel to the Batteries (with heavy cable). Am I on the right track?

 

[Favunclerich]

Your inverter should be mounted as close to the batteries as practicable and in a dry spot. Mine is in the cave, and not connected to the DC distribution panel. You're correct that the cable to the DC distribution panel may not handle the added load. There should be separate cables, either from the battery buses or the batteries directly to the inverter. I think the manual also calls for a fuse, and an on/off switch is a good idea, too. The total length of the positive cable for the DC portion of the system can be less than six feet if you mount the inverter in the cave.

As far as the AC side of the system, you have choices. The Xantrex inverter has an AC outlet directly on the unit. If you use this outlet, you don't need to do anything further. Just plug your appliances into the outlet on the inverter. If you want to use the outlets already built into the boat, you'll need to connect the inverter using a separate, grounded AC cable from the inverter to the AC distribution panel. Presuming that you don't have a generator, you can use this empty space on the panel. There is a slide on the panel to prevent you from using both the inverter and shore power at the same time. You just turn on either the shore power switch or the generator (inverter in your case) switch, and that will connect your inverter to the AC system of the boat. You can then turn on the switches for the outlets (dining area, galley area, etc.) and use them as though you were plugged into shore power.

I suggest that you hire an electrician if you're not sure how to make the various connections properly or calculate the cable sizes required for your particular installation.

 

[gerlots]

After doing some deep investigation, by removing the panel in the V berth in front of the helm, I saw that a wire was conected to the inverter breaker. The wirers were headed aft. Now since I don't have a Generator, I found that the wire was not connected to anything. After doing a continuity check, Same wire! Prewired! The rest was easy. Short run to the batteries, a pre-wired connection to the the panel. The inverter is mounted in the Generator space, with a 250a fuse to the battery, and a slide lock between the inverter breaker and the shore power breaker. Done!
Thanks for all the input. This is a great Forum with lots of good info.