Battery tender

[cyberdork]

I bought a battery tender and am wondering what setting I should use. It's a 12volt tender with I believe a 1.5amp and 3 amp setting. Which setting should I use for storing it over winter?

[gs1197]

my vote is 1.5.
3 would probably cook your battery if left on for very long.

[brveagle]

Is it free floating?

If it is, just plug it in on 1.5 amp and leave it on all winter

[rudy]

I have a 900mA that goes into maintain mode when the battery is full. I leave it plugged in all winter.

[Florida Guy]

I have a BT jr. which is .75 amps.
I just leave it plugged-in all the time when not riding.

[tas850g]

I too have a Battery Tender Jr. from Drag Specialty. It does not allow you to switch charges from 1.5amp and 3amp. The tender monitors the amount of charge and maintains that charge. The instructions that came with it should be able to explain how it works pretty well. It works great i use it on my bike and lawn mower during the winter.

[schlyme]

i have the jr too. i love it. just plug n play

[bakalorz]

I bought a battery tender and am wondering what setting I should use. It's a 12volt tender with I believe a 1.5amp and 3 amp setting. Which setting should I use for storing it over winter?

Is your charger's brand name "battery tender", or are you using it as a generic description for the charger.
If a generic description, is it a trickle charger or a float charger.

A trickle charger is the simplest, it puts a low fairly constant current into the battery for as long as it is hooked up. It will slowly bring a discharged battery up to full charge. After that (or if hooked up to an already charged battery) it will slowly overcharge it. Done for a short time, not too often, this causes no real harm. If you periodically do it for a specific recomended time, or measure it with a meter, it can be a marginally ok way to maintain your batteries over the winter. Forget to disconnect it for long enough and you WILL damage the battery.
The hassle and potential danger of this method make it not really worth it.

A float charger is similar, except that once it hits a specific voltage (the "float" voltage, usually 12.8 to 13.4 or so volts) it will maintain this voltage, and the charging current will taper down to virtually nothing. You can leave a battery connected to one pretty much indefinately without damage. You can also store a battery off the charger, but periodically connect it to the float charger for a bit if that is more convenient, which works about as well. In that case the charge time is not as critical as it would be with a trickle charger.

There are also various "fast chargers" which will charge a discharged battery up to full charge. These are not specifically intended for storage, and WILL RUIN a battery if left connected for more than a few hours at a time. They can be used for storage by connecting them for a couple of hours once every couple of weeks. But they must be disconnected in between those times.
This type of charger would be the most likely to have a "1.5 amp and 3 amp" setting

A brand name "battery tender" is a microprocessor controlled fast + float charger. It will fast charge a battery to a high voltage (14.4 volts) hold it there for a certain time and then go into float mode (13.2 volts)
This is useful if the battery you are putting into storage is slighly discharged when you go to store it, but fairly irrelevant if the battery is already fully charged when you store it.
Like a float charger you can leave it connected continuously to a battery in storage, or you can connect it for a couple of hours once every couple of weeks ... whichever is most convienient.

----

In order to give you usefull advice instead of best guesses, we would need to know what you actually have.
Manufacturer and model # with a link to webpage, or detailed specifications, or complete instructions would be a start.

The safest thing I could advise given the little bit you have told us so far is:
Once every two weeks set the charger to 1.5 amps and connect it for 2 or 3 hours. Then disconnect it until 2 weeks later when you repeat the process. Continue to do this all winter long

[willie]

FWIW, I've found a cheap trickle charger plugged into an appliance timer set to turn on for 1-2 hrs a day to be very inexpensive way to keep my battery charged during off seasons. It worked really well on the battery for my lawn tractor. I figured it should be the hot but cheap ticket for my bike batteries as well. I'd greatly appreciate the opinion of others.
Thanks
Willie in TN

[bakalorz]

FWIW, I've found a cheap trickle charger plugged into an appliance timer set to turn on for 1-2 hrs a day to be very inexpensive way to keep my battery charged during off seasons. It worked really well on the battery for my lawn tractor. I figured it should be the hot but cheap ticket for my bike batteries as well. I'd greatly appreciate the opinion of others.
Thanks
Willie in TN

I'd probably recommend a bit less often than that (an hour or two a week maybe) but its not a bad idea. OTOH, if the battery is not losing too much water, I guess its good as is. If you have a voltmeter, make sure that the battery is not getting over 14.4 volts at the end of each charge cycle, if it does, then definately cut back.

Also, this will work well with some chargers, but be a disaster with others.
Some chargers (probably most trickle chargers) will have a diode preventing reverse current.
Others chargers don't have a diode on the output, and will discharge the battery if left connected to the battery but not powered by A/C (for example the harbor freight $6 charger)

[Steve]

For those that might be shopping for a "battery tender", but the Battery Tender brand from Deltran seems a bit expensive, consider the Schumacher Battery Companion. Last time I looked, they were 18 dollars and some change at Wal-Mart, making it under $20 after tax.

It might not have quite all the computerized gadgetry of the Deltran unit, but it does charge at 1.5 amps, then go into a float mode. I have had at least four of them here for several years, keeping all my off-season toys ready to go, and they do a fine job.

.

[dpep]

How does $6.99 sound to you?

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=42292

[willie]

That's more in line with my budget. I wonder how good it can be for that price. Anyone out there with experience with one of these units? I also wonder about the mfg's quality control.
Willie in TN

[tkent02]

That's more in line with my budget. I wonder how good it can be for that price. Anyone out there with experience with one of these units? I also wonder about the mfg's quality control.
Willie in TN

Mine works fine to slowly charge a battery, although I never need to use it.
Wouldn't leave it plugged in all winter and expect the battery to work very well.

[bwringer]

Is your charger's brand name "battery tender", or are you using it as a generic description for the charger.
If a generic description, is it a trickle charger or a float charger.

A trickle charger is the simplest, it puts a low fairly constant current into the battery for as long as it is hooked up. It will slowly bring a discharged battery up to full charge. After that (or if hooked up to an already charged battery) it will slowly overcharge it. Done for a short time, not too often, this causes no real harm. If you periodically do it for a specific recomended time, or measure it with a meter, it can be a marginally ok way to maintain your batteries over the winter. Forget to disconnect it for long enough and you WILL damage the battery.
The hassle and potential danger of this method make it not really worth it.

A float charger is similar, except that once it hits a specific voltage (the "float" voltage, usually 12.8 to 13.4 or so volts) it will maintain this voltage, and the charging current will taper down to virtually nothing. You can leave a battery connected to one pretty much indefinately without damage. You can also store a battery off the charger, but periodically connect it to the float charger for a bit if that is more convenient, which works about as well. In that case the charge time is not as critical as it would be with a trickle charger.

There are also various "fast chargers" which will charge a discharged battery up to full charge. These are not specifically intended for storage, and WILL RUIN a battery if left connected for more than a few hours at a time. They can be used for storage by connecting them for a couple of hours once every couple of weeks. But they must be disconnected in between those times.
This type of charger would be the most likely to have a "1.5 amp and 3 amp" setting

A brand name "battery tender" is a microprocessor controlled fast + float charger. It will fast charge a battery to a high voltage (14.4 volts) hold it there for a certain time and then go into float mode (13.2 volts)
This is useful if the battery you are putting into storage is slighly discharged when you go to store it, but fairly irrelevant if the battery is already fully charged when you store it.
Like a float charger you can leave it connected continuously to a battery in storage, or you can connect it for a couple of hours once every couple of weeks ... whichever is most convienient.

----

In order to give you usefull advice instead of best guesses, we would need to know what you actually have.
Manufacturer and model # with a link to webpage, or detailed specifications, or complete instructions would be a start.

The safest thing I could advise given the little bit you have told us so far is:
Once every two weeks set the charger to 1.5 amps and connect it for 2 or 3 hours. Then disconnect it until 2 weeks later when you repeat the process. Continue to do this all winter long

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I use a Shuhmacher battery maintainer myself. Also very high quality, and not as expensive as the Official Battery Tender Brand stuff.

As noted above, the cheapo wall-wart trickle charger from Harbor Freight is not controlled (and thus could overcharge your battery) and does not have a diode, so when the power is off, current reverses and slowly discharges your battery. Hook one up to your battery, turn off the lights, and unplug it from the wall -- you'll see its LED glowing weakly. Not good.

There's frugal, and then there's just plain cheap. If you can't afford anything better than the HF charger, pick up an extra lunch shift at McDonald's or something.