[Brian Belcher]

I finished up a major project on my Z276 today and it was a bear but well worth it.
I now have everything 120V-AC on the inverter and I used two deep cycle batts to run it all. The genset now ony powers the 3 bank charger. I parallelled the deep cycles for boat power and have a regular cranking batt for the boat engine and it's systems (DC). I took the shore power and connected it to the charger through an isolator and have another isolator between the two sets of batts so as the inverter never draws from the crank batt. The stock alt still charges all three through the isolator.
Next is to set the generator up to come off idle only when needed to charge the deep cycles and it looks like I will have to get that governor (?) from Honda. If I can't get something that will work with my Kohler or is too expensive, I'll just start the genset as needed or let it run.
On the genset, I was worried about the 3600rpm that Kohler says it needs to be. I finally got to stay dead on but got to wondering what the freq was at that rpm. 67 hertz!!!!
I backed it off till it was 59.97 hertz. The rpm is now 3400ish.
Any ideas on the idle up or auto start-auto kill for low batt voltage ?
I am also thinking I'll end up changing to 4, 6volt batts for more ah's. I'm going to see how long the batts last with A/C, and TV-stereo amp running all night.


4000 WATT PURE SINE INVERTER CHARGER 12 VOLTModel # PICOGLF40W12V120V is the inverter I got used for $400. The hefty price is cause it's a true sine wave and not a step sine. No motors singing due to hacked up sine wave.
I used all 2/0 copper cable cause that we use at the power company. (we were throwing it away !! REALLY!!)
I compressed all copper lugs with an O=die tool from work, soldiered and shrink wrapped.
One inverter brand I have know idea. Came on the boat. The other is one I had from Warn that is 10 yrs old, at least, that never got put on my Jeep. I mounted an under ground pedestal parking stand for the grounds and neutrals.
A bit of advice, if you're going to do an inverter, make sure it is a true sine wave one. You can get ones much cheaper than the one I have, over $800 new, and you might get lucky and find a high quality like mine for sale. Trust me, stepped sines are hard on motors.

Now, I'm all ears.....

[Hudson River Steve]

Brian,
You sure are an ambitious guy! That's a big job. That is a nice inverter for only $400, they are usually double that or more. The original inverter installed on our boat was made by Xantrex but was only 2.5kW. Xantrex also makes a panel that will auto start your generator when the battery voltage goes low or if your a/c starts Power Accessories | Automatic Generator Start | Xantrex. I am sure there are other options as well. Doesn't your inverter have a low voltage generator start output? The batteries will not last long if running the a/c.
How did you check the frequency and RPM of the generator? It sounds like one of your instruments is not calibrated properly. Kohler is correct, in order to achieve 60Hz the genset needs to run at exactly 3600 RPM.

[Brian Belcher]

Hudson Steve, my boat was missing it's inverter when I bought it. I never found evidence that it ever had one either. !997 come with one ?
You just answered the question I needed answered too. Didn't think about the panel inside operating the genset. Now to find one.
It's not a big deal at all. In fact, I can move everything back to the way it was, fairly easily. Just worried about the charge rate vs. the draw on the batteries. Will the charger charge faster than what I'm using?
Find out Friday night.

[Hudson River Steve]

Brian,
If your boat came with a generator then it most likely never had an inverter installed. With respect to how fast your batteries will be charged, how many kW is your Kohler generator?

[Brian Belcher]

4kw.
Steve, does your boat have the inverter AND genset ? I'm asking because you may have just killed my feeling of accomplishment ! I thought I'd come up with something original on a boat. (well, kinda)
The only factor for the particular inverter I installed is that is the one we use in our sub stations for battery back up in th switching house. They last forever as far as in our line of work. PLUS, I got it at a great price after our sub station boys up graded one of our subs.
Ass-u-meing that you do have the inverter, where is it mounted ? I have mine in the engine bay but would love to get inside. Heat plays a factor on the performance of these things.
BTW. I know what you were saying about the 3600 rpm on the genset. I had it at that rpm but 67 hz is TOO HIGH. Todays electronics can easily absorb that but I'm a serious perfectionist. Seriously !

I appreciate any info you have.

[Hudson River Steve]

You can still feel accomplished and original, my boat only has an inverter...and no a/c.
My inverter is mounted in the aft most locker in the berth. It is essentially mounted to the "firewall" just on the cabin side rather than in the engine compartment.
You are correct, heat is the enemy of semiconductors but your inverter has a protection circuit to ensure it won't cook. According to the manual for your inverter "The inverter will go to Over temp protection when the heat sink temp. ≥105ºC(221℉), and go to Fault (shutdown Output) after 30 seconds. The switch has to be reset to activate the inverter." I guess it just depends on how much your engine bay cools off. The hotter the engine bay the less amount of power you can push through the inverter.
What type of instruments did you use to measure the frequency and RPM. Engine Tach's are typically only good to about 3% and sometimes less.

[Brian Belcher]

The tach is a hand help Echo Appuma unit. Works in 10 rpm increments. My frequently is with a high dollar Idea multimeter. It's one we use at the electric company. Much better than any Fluke.
I'm going to get some pics this weekend of the set up. I would now but discovered my iPhone is not water proof.
Yep
Took granddaughters swimming the other day and forgot to take phone out of back pocket. Have it in bag of rice right now.
Keep your fingers crossed for me !,,

PA. Please don't be mislead. This NOT a brand new inverter. It is probable 10 years old. It just hasn't been used much.

[Brian Belcher]

Steve, I assume it's Steve , how long will your batteries go with what appliances?
Don't you have a Z280?

[Hudson River Steve]

Brian,

You were right to use the DMM to measure frequency, they are typically good to about +/-0.1% or +/- 0.6Hz. Your tach was probably skipping pulses or just inaccurate which is why it was only reading 3400 RPM. Good to know for future use.

Yes I have a Z280. I have a single large Group 4D battery (100 lbs) that is dedicated to the inverter. I have never drained it completely but I do not use a whole lot of ac power. It runs a flat screen TV (~30W) and the occasional electrical accessory such as a vacuum, cell phone/iPad charger etc. I will also use it to run the microwave (700W) at dinner time. I have never used the cook top in the galley. I have a gas BBQ for the heavy cooking. The battery is rated for 295 minutes at 25A which is about 125 A-hr. It will run a TV for a day and a half non-stop, plenty for me.

Steve

[Brian Belcher]

Thanks for the info on the AGS from Xantrex. Going that route instead of trying to idle the genset down and it run nonstop at night.
Can't get it till next month due to the new gimbal pin and ring and bellows and etc, this month.
Son and I are headed to lake tomorrow to put what I have through some sea trails. I've been instructed by the true Captain that the important system is the A/C. If there are any issues, I'll swap it back to original set up.
Sidenote. I borrowed a buddies timing light that has the tach on it. Running at 3620rpm. Throwing my old small engine tach away.
It's good to talk to you.