New 280DA owner - how do I use genny, AC, DC, etc.?

BigJer

Member
Jul 15, 2010
32
East Tennessee - Tennessee River - Watts Bar Lake
Boat Info
5kw Kohler, Garmin 172C
Engines
Twin 5.0L Mercruiser w/BIIIs
The day finally arrived - the boat is now on the water, but one thing is confusing me. When using the genny, I still have to turn on the switch for lights in the 12vdc section on the switch panel to get cabin lights. Am I using dc or ac for the lights? Am I depleting the charge on my batteries? What are the AC light and DC light swithes (just behind the stove top) for? See, I'm confused. Please help. The manual is confusing at best. :huh:

Also, can I safely run the genny while underway?
 
What are the AC light and DC light swithes (just behind the stove top) for?

Above the stove is a light fixture.

Inside this light fixture are two different light bulbs. One is 12V and runs off your battery, one is 120V and runs off 120 V AC when available.

You can turn on either or both.
 
When using the genny, I still have to turn on the switch for lights in the 12vdc section on the switch panel to get cabin lights. Am I using dc or ac for the lights?

You are using 12V DC from the batteries.


Am I depleting the charge on my batteries?

Yes



To counter this simply turn on the “AC Converter” the top right breaker in the AC electrical panel when you are connected to shore power or have the generator running.

In your mind, think of this “AC Converter” as a battery charger that works when you have a 120V AC source like shore power or have the generator running and the main AC breaker on.
 
You are using 12V DC from the batteries.




Yes



To counter this simply turn on the “AC Converter” the top right breaker in the AC electrical panel when you are connected to shore power or have the generator running.

In your mind, think of this “AC Converter” as a battery charger that works when you have a 120V AC source like shore power or have the generator running and the main AC breaker on.
Thank you! So am I understanding you correctly: with the AC Converter turned on, I am still using 12vdc for the cabin lights (of course, they're dc bulbs), but the genny is now charging the batteries, yes?

Also, the battery "selector" knobs in the cockpit (where the ignition keys are) - I had to turn on the one on the right before the genny would start. Is that all that knob is for?
 
Is it okay to run the genny while underway?

In general, yes. The primary problem with generators (and the reason they stir a lot of angst) is that they are internal combustion engines that generate carbon monoxide as a byproduct of incomplete combustion. It is generally odorless and colorless and people exposed to enough of it simply fall asleep and ultimately die...which is not good boating. As long as they are properly vented, and you are moving, and there is no "station wagon" effect...generate away. Because of the way carbon monoxide (CO) interacts with your respiratory system, it can kill you with very little advertisement. Historically though, there have been examples of generators venting into populated spaces (really bad idea), not venting at all when you are stopped (really bad idea) and exhaust fumes circling back onto decks while underway due to air flow from camper tops, etc. (really really bad idea). It is a pretty good idea, if you are going to run the generator, to invest in carbon monoxide detectors (marine are more expensive than household applications) for the cabin AND for the deck.
 
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Is it okay to run the genny while underway?

Yes, you can. But the value is limited. The engine(s) will be supplying electricity to charge the batteries. The engine(s) will also be heating the water in the water heater. The 12 v/ 110v frig is actually a 12 v machine with a built in inverter to turn 110 in 12. So its actually more efficient to run it at 12 vdc. I suppose that you could run the gen to keep the heat or aircon going, but we have found (having no gen) that the cabin cools down pretty quick once we get to shore power. About the only other thing I could think of is nuking popcorn while underway.

Henry
 
Yes, you can. But the value is limited. The engine(s) will be supplying electricity to charge the batteries. The engine(s) will also be heating the water in the water heater. The 12 v/ 110v frig is actually a 12 v machine with a built in inverter to turn 110 in 12. So its actually more efficient to run it at 12 vdc. I suppose that you could run the gen to keep the heat or aircon going, but we have found (having no gen) that the cabin cools down pretty quick once we get to shore power. About the only other thing I could think of is nuking popcorn while underway.

Henry
Hey Henry, common sense prevails! Tell the kidos no popcorn 'til we stop.
 
So am I understanding you correctly: with the AC Converter turned on, I am still using 12vdc for the cabin lights (of course, they're dc bulbs), but the genny is now charging the batteries, yes?

Yes. The bulbs are 12Volt. AC/DC does not matter, they need around 12 volts.


Also, the battery "selector" knobs in the cockpit (where the ignition keys are) - I had to turn on the one on the right before the genny would start. Is that all that knob is for?


Boy, that’s a more difficult one to explain.


First, no, I do not believe that is the only thing this switch controls.


Over the years with various engine configurations and various setups, some 280 Sundancers with generators and some without, some with single engines, some with twin engines that answer varies.

In general, some things are not run thru the battery switches, one example of this is the bilge pumps. This is for safety.

Some things are run off one side, called a battery bank, some off the other. In a twin engine setup one bank (one or two batteries) is for one engine and the other bank (one or two batteries) is for the other engine.

At the helm next to the start buttons is an emergency bottom. Think of this as a pre-wired jumper cable. Press the button and you just remotely put jumper cables on between your two main battery banks. Technically that is not what is going on but for explanation purposes this helps you understand what is happening.

If you are anchored and run one bank down to where you can not start one engine you simply start the other engine, press this emergency button then while holding this button down you press the start button for the non-running engine. Once the other engine starts you can let go of the emergency button.

Now that generator. It can be wired to the first bank, the second band, or have a battery all of its own.

The easiest way to figure out what item is powered from what battery bank, turn it off, try stuff, turn it on, try stuff, do the same with the other bank until you know how it all works in your boat. Turn off both switches and see what still works. Test your bilge pumps by turning the test knob with both switches off to make sure it’s wired correctly. Once you got it figured out label them.
Its gets more complex than that. Sorry. I’ll try to keep this brief.

#1) Never switch the battery switch to ‘off’ with the engine running. You can damage expensive parts.

#2) You may have starting batteries and deep cycle batteries. At anchor with the engines off the deep cycle batteries are the ones you want to use.

#3) After a brief warm up period, keep a load on your generator, don’t just let it run with little load. You may need to turn on the hot water heater, converter, air conditioning, but you need to keep it reasonably loaded or over time you can do harm to the generator’s motor.

#4) Keep the engine compartment exhaust fan on at least 4 minutes before, 100% of the time during and a good 5-10 minutes after you use your generator.

#5) Add extra CO detectors. We have 3 and I test them often.
 
We run the gen while underway on really hot days to keep the a/c running and so the kids can watch a movie when they need to get out of the sun.

As already noted -- invest in CO detectors. I'm kind of paranoid about it so I have 3 in the cabin. One in the mid-berth, one in the dining area, and the built-in detctor in the forward berth.
 
We run the gen while underway on really hot days to keep the a/c running and so the kids can watch a movie when they need to get out of the sun.

As already noted -- invest in CO detectors. I'm kind of paranoid about it so I have 3 in the cabin. One in the mid-berth, one in the dining area, and the built-in detctor in the forward berth.
I'm getting paranoid now. I'm gonna' replicate your setup.
 
Good info, thank you. Do you trust the Sea Ray provided CO detector in the cabin, or do you buy another as a redundant protection mechanism? I'd hate to wake up one morning dead.

Yes, I trust the built in detector but I test it regularly. They are good for about 3 years and you can get them re-certified from the factory for $25.

Here's the website and a quote from the manual:

http://www.fireboy-xintex.com/co-detectors.html

FACTORY RE-CERTIFICATION AND
WARRANTY RENEWAL PROGRAM
Because of the unique sensor and circuit design characteristics of a carbon monoxide alarm, it is
not possible to field test the CO Sentinel. The Xintex Recertification and Warranty Renewal
Program provides peace of mind by offering factory re-certification and a new one year warranty.

Return the CO Sentinel to the factory, prepaid, along with your check or money order for $25.00*
at any time to take advantage of this program. This service includes complete testing of circuitry
and sensor. Repairs, re-calibration, or sensor replacement are included. In addition, you will
receive an additional 12-month limited warranty. This offer does not include replacement or
repair of units that have been damaged through misuse, carelessness, misapplication, altered or
otherwise been destroyed as a result of fire, collision, or sinking. Should the returned CO
Sentinel require repairs from misuse as described above, you will be notified of the cost prior to
repair.

Include your return shipping or mailing address and telephone number along with the CO Sentinel
and mail to:
Re-certification Department
Fireboy-Xintex, Inc.
PO Box 152
O-379 Lake Michigan Dr. NW
Grand Rapids, MI 49534
 
Is it okay to run the genny while underway?

My answer is yes, that is what the thing is there for so use it.

There are three times when you want 120 volts. At the marina, when you are moving and when you are not moving away from shore power.

At the marina you have shore power so you may as well use it.

The other two you don’t have shore power so this is when we use the generator.
 
Now onto the humor side…….warning…….this may offend some people.

Most people at the marina will understand how your air conditioning works. That thru-hull shooting water out of the side of your boat is for the air conditioning.

With your generator you will be in remote areas with the ability to run
your air conditioning. Well intending nice people will inform you that your boat is sinking.

They see the water shooting out and associate that with a bilge pump trying to overcome a leak.

Well, after explaining the true reason for the water shooting out of the forward thru hull to many people I decided to listen to that little evil voice inside my head.

Now when a person tells me about this water I first say something like they are kidding. My look is that of disbelief. After they persist I get up, drink in hand then take a look. Then I give them a look of shock, followed by a look of confusion then finally a look of acceptance.

My response will be “Well, the boat is not getting any lower in the water so the pump must be keeping up with it. I think we are OK!” After nodding my head in agreement with myself I sit back down and keep drinking with a smirk on my face.
 
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Okay, you're bad! When I went to sea trial, I asked "there wasn't that much water in the bottom of the boat, how is it getting in there?". He was much kinder than you (I guess since I was about to buy the boat). But.... I'm using your line the first chance I get.
 
NICE PURCHASE!
If you haven't already... I know it's long but it's really great...

http://clubsearay.com/forum/showthread.php?t=10064&highlight=OFFICIAL+280+THREAD

You make me remember how I felt when I first bought this boat(not like I know everything now!:grin:)

On mine- The battery switch that has 1,2, both is the house batts.. and starting for the port engine...

The on off batt switch is for starboard engine and generator starting only!
 
NICE PURCHASE!
If you haven't already... I know it's long but it's really great...

http://clubsearay.com/forum/showthread.php?t=10064&highlight=OFFICIAL+280+THREAD

You make me remember how I felt when I first bought this boat(not like I know everything now!:grin:)

On mine- The battery switch that has 1,2, both is the house batts.. and starting for the port engine...

The on off batt switch is for starboard engine and generator starting only!
Thanks to KHARRIMAN. My battery switches turned out to behave the same way.
 
This thread has been a huge help, but now I have an actual problem with equipment as opposed to just being ignorant of the equipment (or maybe it will just turn out to be newbie me).

The scenario is: sitting at the dock for about 5 hours running the genny (don't have shorepower completed yet to my dock). Went out for the afternoon, never turning off the genny. About 3 hours later powered up to go home. Got back to the dock and noticed the blower was off (scared me big time). It wouldn't come on. After letting the bilge cool down, found the breaker for the bilge blower, and it was tripped. This has happened twice in two days. Am I overusing the blower? Is the genny making it too hot in the bilge? I'm such a newbie.
 
This thread has been a huge help, but now I have an actual problem with equipment as opposed to just being ignorant of the equipment (or maybe it will just turn out to be newbie me).

The scenario is: sitting at the dock for about 5 hours running the genny (don't have shorepower completed yet to my dock). Went out for the afternoon, never turning off the genny. About 3 hours later powered up to go home. Got back to the dock and noticed the blower was off (scared me big time). It wouldn't come on. After letting the bilge cool down, found the breaker for the bilge blower, and it was tripped. This has happened twice in two days. Am I overusing the blower? Is the genny making it too hot in the bilge? I'm such a newbie.

The blower is intended to vent the bilge for the gen and engines so you are not over using the blower. You're blower might be going bad but someone else can chime in on that.

More important is the fact that you are running the gen at the dock...DON"T run the gen at the dock. The CO can accumulate around your boat and others. If you have dock neighbors the CO can slip into their boats undetected --- maybe even several slips down. I don't have the manual handy but I am pretty sure it warns of this.
 

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