protection of the batteries to not run out

[melida]

Hi all.

Sorry for the title, I couldn't find an appropriate one and which forum directory is related.

I heard that in Searay's there is a cut-off system which stops the consumption of the batteries while remains the amps/volts only to start the engine(s). Such as fridge stops when the volt downs to 11,99.

Is it true or city legend or an option?

Second question my boat has emergency start button red marked near the gas engine's start buttoon.

When I excess use the batteries or cant charge them the engine not starts so I push that button and simultaneously turn the key then the engine starts.

So, is this emergency start button is cooperated with the question 1 system or only combines all of the bateries make them "both" position like the battery swich?

Thanks a lot.

 

[melida]

Any comments? thoughts?

 

[Henry Boyd]

I know there is no low voltage cutoff on my 280, leave the lights, fridge, stereo on all night and by morning dead battery!

I looked at your engine pictures posted in the holding tank installation thread. You seem to have a different battery set up than the singel engine gas boats. We have two batteries that are connected so that both batteries are on, either Battery, or Battery 2 is on (while other is off), and all batteries off. You have a pair of what look like group 27 batteries, and one big ole truck battery. Without knowing what kind of battery switch(s) are installed, I can't give you an answer.

I did look at the 2002 single engine diesel wiring diagram in my 280 owner's manual and it shows only two batteries. Have you got wiring diagrams in your owner's manual package?

Henry

 

[melida]

I looked to wiring diagrams of my engine is almost same as single gas engine.
The former owner changed the battery swicth. It was only on and off. He bought four position swich both,1,2,off.
My two little size batteries (in my country that size is called taxi battery) are 105 amps each for starter-engine and belonging to the 1 position of the swich. The big battery is 200 amps for housing-service and belonging to the 2 position.
When I'm out of dock while cruising the swich is on both and while moored-anchored at 2 position.
when I excess use the "2" and try to start the engine on "2" not cranks but while I press to the emergency start button and then turn the key engine starts. Or change the swich to "1" or to "both" no problem engine is starting.

 

[KHARRIMAN]

I had to learn all this battery stuff too so maybe I can help you a bit....
First- Here is a link that I found helpful that someone else posted- especially the chart about discharge-
http://www.windsun.com/Batteries/Battery_FAQ.htm

OK- I looked at the pictures of your batteries as well and i'm no electrician but here's what I think is going on here.
Your two "taxi" batteries are for starting- they look like they are wired in parallel- one single wire to the switch and one wire joining the (+) and one joining (-) together. What that does is give you 12v at twice the capacity. You said 103? amps- I think it's amp hours?
Now... that really BIG battery(200 amps- amp hours?) is probably meant for the house(all lights and electronics) and it sounds like you are using them correctly (1) for starting and (2) for anchoring. When you run down that big battery it doesn't have enough juice to start that big diesel:thumbsup:.
There is NO run down protection that I'm aware of.
The emergency switch acts as a "temporary" bridge between the battery banks allowing the two "taxi" batteries to feed the big battery enough juice to get you started and running with the assumption that the alternators will kick in and start re-charging everything.

Situation 3- If you leave switch on All or Both while anchored(You only have one battery switch right?) you are essentially draining all three batteries and could end up dead in the water. That's how i see it...hope that helps
--Kevin

 

[Go Aweigh2452]

The PO probably installed a BlueSea or equvalent battery system. That system cuts the house out of the system when both batteries are on line and the house drops down to 11.? At that time the bluesea will save enough starting power so you can get going. Mine works well and I highly recommend such a system if you are running a lot of house stuff. Your other recourse would be to select #2 (normally your house) on the MBSS. That will save #1 for starting if you run your house down.

 

[melida]

I had to learn all this battery stuff too so maybe I can help you a bit....
First- Here is a link that I found helpful that someone else posted- especially the chart about discharge-
http://www.windsun.com/Batteries/Battery_FAQ.htm

OK- I looked at the pictures of your batteries as well and i'm no electrician but here's what I think is going on here.
Your two "taxi" batteries are for starting- they look like they are wired in parallel- one single wire to the switch and one wire joining the (+) and one joining (-) together. What that does is give you 12v at twice the capacity. You said 103? amps- I think it's amp hours?
Now... that really BIG battery(200 amps- amp hours?) is probably meant for the house(all lights and electronics) and it sounds like you are using them correctly (1) for starting and (2) for anchoring. When you run down that big battery it doesn't have enough juice to start that big diesel:thumbsup:.
There is NO run down protection that I'm aware of.
The emergency switch acts as a "temporary" bridge between the battery banks allowing the two "taxi" batteries to feed the big battery enough juice to get you started and running with the assumption that the alternators will kick in and start re-charging everything.

Situation 3- If you leave switch on All or Both while anchored(You only have one battery switch right?) you are essentially draining all three batteries and could end up dead in the water. That's how i see it...hope that helps
--Kevin

My taxi batteries each 105 amps hour gives 210 amps and the big one is 200 amps hour.
When anchored I use the big one "2" position of the swich. The refrigirator is always on at level 3, music is on and on summer we drink lots of frapes and winter hot drink so I use the inverter to boil water in kettle and use the mixer for frape. While using a 220 volt tool with ineverter it drains more for example a 1000 watt tool with shore power consumes 1000/220=4.5 amps hour and same tool with inverter 1000/12=83amps hour. Also the outlets refrigator is on same button AC panel so the refrigirator also works by 220 volt for short use of inverter I close refrig and then open. These consumes much of the big 200 amps battery and I spend anchored 8-12 hours at weekends.
But in this condition battery swich "2" engine won't start if I push to emergency button then starts.
I guess there is no battery saver system in my boat but my wife's dad has 2006 240 sunsport (European not sold in USA) has refrigirator and when the batteries comes down 11.99 amps refrigirator stops. So why does 280 not have this?
Best regards.

 

[Henry Boyd]

Couple of things come to mind, One I can't answer why the 240 has low voltage and your 280 does not, other than to say my 280 doesn't either.

Our refrigerators are dual current 110 AC and 12 DC. Isn't yours (although 220 AC)?

Can you get a picture of the battery switch?

I also have to ask, if position 2 is for the big battery, and the big battery is just for house circuits, why do you care if it won't start the engine? Do you need the engine running AND switch set to position 2 to charge the big battery?

Won't all batteries charge when switch is set to 'both'?

Henry

 

[KHARRIMAN]

Agree with Henry...and...
There is no monitor BECAUSE of the emergency start.
I'm assuming that they're assuming<huh> that you don't need to monitor it if you can always start up and recharge with the alternator or switch over and start. But it does give the aftermarket retail guys an in. Just have to get on eof those Blue Sea or equivalent monitors- How bout your smartcraft- That's how I monitor although it reads about 0.3 volts less than a voltmeter.

 

[melida]

Couple of things come to mind, One I can't answer why the 240 has low voltage and your 280 does not, other than to say my 280 doesn't either.

Our refrigerators are dual current 110 AC and 12 DC. Isn't yours (although 220 AC)?

Can you get a picture of the battery switch?

I also have to ask, if position 2 is for the big battery, and the big battery is just for house circuits, why do you care if it won't start the engine? Do you need the engine running AND switch set to position 2 to charge the big battery?

Won't all batteries charge when switch is set to 'both'?

Henry

Henry
my refrigerator is also dual voltage 220 and 12. when I use inverter to get 220 volt(alternativ current) to use a 220 volt tool I have to push the outlets-refrigerators button on AC panel so the refrigerator work with 220 and amps consumed more then 12 volt.
when ı excess use inverter and since I spent too many hours anchored drain the "2" battery and some times need to use number "1" but I cant use because I dont know either a protection or saving system.
As you mentioned If I swich to "2" engine charges it and "both" itis charged.
My curiousness is about the cut-off is to not to carry a portable honda or buy a Kohler generator.

 

[KHARRIMAN]

AAAHHH! Portable GENERATOR!:wow:
Don't ask!:smt043:smt043

 

[melida]

I dont want portable. Its 3000$ (and Kohler 4kv diesel is 20.000$ in my country) its cheap pratic less weight less storage place but COOOOOOO.....
I wont risk my life and my family
I'm always cruising with my wife and we have 3 years old daughter "Melida" (means sended from skys as a gift of God)since she was 3 months.

 

[johngus]

On my boat,the starboard engine has a dedicated battery that the house can't run off.I always keep my switch to either 1 or 2 when anchored.this way I can't run down both my house batteries.My boat has 3 batteries.2 house and 1 for the starboard engine.The starboard should always be good when anchored and even if the house battery runs down the emergency start switch will jump the dediacated starboard engine battery with the port engine battery,always getting both engines going.

 

[Henry Boyd]

Johngus,

I can't comment on the wiring of your boat because I can't reference its wiring diagram, but I can say the 280 twin engine wiring is different. I have been on boats that have house circuits completely independent of engine circuits, but the 280 isn't wired that way.

On the 280 the port engine has the single battery. The 280s also use EIM (Electronic Interface Modules) that act as relays, breaker panels and power distribution devices. While there are some independent DC house circuits (cabin lights, head, frig), the water system, cockpit lights, compartment lights, electronics, stereo, run through the EIMs. This makes truly having an isolated house circuit difficult. The twin engine 280 (according to 2002 wiring diagram) has DC power to all circuits (with exception of opposite engine related functions). Electrically either battery side supplies power to the whole boat.

While it may be an operational practice to treat one side as house and the other engine only, it is not that way electrically.

That brings us to the issue on Melida. He has a non standard setup. The standard setup is two batteries, that can be used either mutually exclusive of the other, or in parallel to provide double amps for engine starting.

A Previous Owner installed a third battery and inverter. My first thought was that the PO maintained the functional equivalence of the two battery single engine setup by keeping the two original group 27 batteries permanently connected in parallel as position 1, and adding a new larger battery as position 2.

But based on the description it seems the PO created an engine only circuit and a house only circuit, and an emergency cross over switch.

At this point I think we have moved out of an area where we can help. The boat has been modified and we can't tell from where we sit. Most efficient solution would be to engage a local marine electrician to review the system and explain how it functions.

Henry