Battery Charger

[Bob Meola]

When charging batteries using shore power do you need to have battery switches on the on position or do you leave off? Boat is a 265 Express

Thanks

 

[Doc Stressor]

Off position. Certainly not the Both position.

 

[Slacktime]

If you have anything running such as a fridge, you will need to have a switch on or the appliance won't work. Hopefully your bilge pumps are wired properly and you won' t need the switch on for that.

 

[Fowl Hooked]

I keep the fridge on to keep the beer cold so I just leave the switches on while charging on shore power. My earlier research into this indicated that with a high quality smart charger it was okay to charge the batteries even while they were under load. There may be a long term impact on battery life but I've been doing it on my 265 for several years with no problems to date.

 

[Doc Stressor]

It's really not a good idea to leave an intermittently cycling load like a refrigerator on when using a dedicated battery charger, even a smart charger. When the refrigerator cycles on, the voltage drop causes the charger to change the charge profile. This typically puts it back into the bulk charge range. This can result in some degree of overcharging and reduce battery life.

Now if your boat has an RV type converter-charger, you should have no problem. These devices keep the batteries isolated from the load when connected to shore power.

 

[drbatts]

I keep the fridge on to keep the beer cold so I just leave the switches on while charging on shore power. My earlier research into this indicated that with a high quality smart charger it was okay to charge the batteries even while they were under load. There may be a long term impact on battery life but I've been doing it on my 265 for several years with no problems to date.

I do the same with my boat. I normally replace my house battery every 2 seasons anyway, so I cannot comment on battery life. I can say the only downside with this is that if the power goes out, or some idiot unplugs the shorepower while the boat is unattended then you will come back to a dead house battery and warm beer.

 

[Fishtales]

I leave them on. Have for 16 years between 2 boats. Never an issue and batteries seem to last very well.

 

[Tucker]

Every 2-years?? Holy smoke! That sure doesn't seem right.

The Doc is usually spot on with just about everything, but I question the harm it causes leaving the charger on with the fridge. Been doing it for years.

I leave them on. Have for 16 years between 2 boats. Never an issue and batteries seem to last very well.

 

[SmokyMtnGrady]

I think what Doc is saying a discharged battery is like a static load where the charger experiences a peak load that slowly is reduced as the battery charges. It is "predictable" where a computer controlled charger can deal with it.

A fridge on electrical power cycles on and off. This variable load can damage the solid state chargers. My shore charger for instance does this test to see the state of the battery before initializing charging. I dont think it will start to charge if there is a fluctuating draw on the circuit.

I have a fridge in my camper that is either gas or 110. I have had a fridge that would run on12v. I don't recall the amperage draw on it though.

 

[Legend]

I leave the batteries on and the charger on. Refrig is always on and I keep a fan running during high humidity. Guess the fan ruuns directly from shore power and does not impact the battery. Have very good life from batteries

 

[Tucker]

If the battery was fully charged to begin with, I didn't think the charger would noticed the frig cycling on or off. I thought the charger would notice the battery being drained and begin to gradually generate the required amps to maintain a full charge. I notice when I first turn my frig on it will still cycle off briefly even if it hasn't reached the set temperature. This is when the charge catches up.

I think what Doc is saying a discharged battery is like a static load where the charger experiences a peak load that slowly is reduced as the battery charges. It is "predictable" where a computer controlled charger can deal with it.

A fridge on electrical power cycles on and off. This variable load can damage the solid state chargers. My shore charger for instance does this test to see the state of the battery before initializing charging. I dont think it will start to charge if there is a fluctuating draw on the circuit.

I have a fridge in my camper that is either gas or 110. I have had a fridge that would run on12v. I don't recall the amperage draw on it though.

 

[Angler Management]

I'm having "ghosts in the machine" issues related to this draw off my House Bank. There are times, not every time, where the house will be dead despite the charger working well. I believe it has to do with the charger "Lead 1" being hooked to the incorrect bank... I'm getting some good research in some of the older forums, particularly might want to read Hookup 1's post on Oct 17, 2007 and the posts afterward about the ProSport Mariner 20. It's a great charger, but there is one way you can get into trouble if you're leaving a draw on the house bank. I'm still not 100% sure this is my issue, but having been researching this I think it applies to this discussion.

However, the way I use my boat I'll not be changing anything I do. Just something to be aware of.