Battery Charger info needed.

[plow]

Pops bought a electric chain saw on a stick, 18V, Troy Built iirc. The batteries are pretty sad. My thinking is buy a few 6V7 to 12AH SLA batteries, Run them in parallel with say a 15' extension cord to be able to wander away from the pack a bit. Pops rides around on a Kawasaki Mule to trim trees an such.

My question is, Will the existing charger (I'll have to look an see what type battery came on it) charge my SLA's? If not. What type will?

Thinking out loud here.........It sure would be nice to be able to come off a 12 volt battery and make this work. I have 24V chargers and access to 12V whatever AH batteries I need. How would applying 24V to a 18V motor affect it? It's only 6 little volts after all.

 

[JDishong]

Understand placing batteries in series "adds" voltage, but in parallel adds the current (not voltage) . If placed in parallel, you will double the current capacity, but Voltage will be 6V still .. won't work on a 18V circuit.

What is the current draw on the motor? .. this will help you select proper battery

What is the current rating on your existing charger?

Depending on controller circuits, 24V could damage the motor and/or controller circuit. Motor would run very innefficient, over heating, and draw excessive current until failure... ie not good.

Better off buying 18V battery.

 

[zkling]

Pops bought a electric chain saw on a stick, 18V, Troy Built iirc. The batteries are pretty sad. My thinking is buy a few 6V7 to 12AH SLA batteries, Run them in parallel with say a 15' extension cord to be able to wander away from the pack a bit.

As JDishong said, you will need to series 6v batts to get 18v. However in series their AH is not increased.

My question is, Will the existing charger (I'll have to look an see what type battery came on it) charge my SLA's? If not. What type will?

It should work, would have to look at the output of the charger.

How would applying 24V to a 18V motor affect it? It's only 6 little volts after all.

It would run really fast till it over heated. Yea it is "6 volts" but 33% more voltage than it was designed to run. Speed and heat will drastically increase. May work for a short period of time, then you may let the magic smoke out.

Better off buying 18V battery.

Agree 100%

 

[stingry]

Rube Goldberg would be proud!

Cheers
Steve

 

[hifi_hokie]

What is the current draw on the motor? .. this will help you select proper battery

As well as an "extension" cord. Adding extra length to a high-current DC line isn't as cheap as simply plugging in a 50' run of 12/3 like AC...big part of the reason why Edison's DC idea lost to Tesla's/Westinghouse's

 

[theoldwizard1]

As well as an "extension" cord. Adding extra length to a high-current DC line isn't as cheap as simply plugging in a 50' run of 12/3 like AC...big part of the reason why Edison's DC idea lost to Tesla's/Westinghouse's

If you are talking less than 25' don't worry about it. Use a 2 wire 12 gauge extension cord and cut the ends off. You might get by with a 14 gauge cord, if we knew the current of the motor.

Depending on how long you are going to use that saw for, you might get away with a smaller and cheaper battery. Checking around, 6V4.5AH batteries are actually cheaper than 6V1.2AH batteries.

You need to charge the batteries separately with a 6V charger like a [URL="http://www.amazon.com/Battery-Tender-021-0127-Junior- Even this small one will get one of those batteries full charged in about 6-12 hours.

Try not to fully discharge those batteries, which is a good case for buying large AH ones. They are not designed for deep discharge.

 

[nehog]

...
My question is, Will the existing charger (I'll have to look an see what type battery came on it) charge my SLA's? If not. What type will?
...

If the present batteries are SLA then yes, otherwise no.

Charging SLAs without damage requires a charger designed to charge this type of battery.

 

[plow]

Series! Yep, I get them mixed up.


Didn't have time to go by Pops house today and look at the saw and the charger, I'll get by there tomorrow.

18 volt it tis.

Magic Smoke to remain contained.

WTH is Rube Goldberg?

Charging three 6v batteries separately is going to be a pita. I'll need to charge at 18. Y'all think one of my 24v chargers could be modified somehow to charge at 18v?

Thanks for the input guys.

 

[Ryf]

you need 9 batteries, hehe, 3 parallels of 3 in series. then you have 18 volts and more amp/hours... but really, if your gonna do ALL that, and spend the dimes, get a 110v weedeater, they are cheaper and will be way less hassle. way easier to tug a cord around than a bank of batteries... or if mobility/lack of energy is a concern, get a alternator and an engine and run that thing on 14 volts instead.. good luck!

 

[Rhyno]

Rube Goldberg would be proud!

Cheers
Steve

Haha...thanks for the

 

[zkling]

WTH is Rube Goldberg?

http://lmgtfy.com/?q=Rube+Goldberg

 

[G_P]

you need 9 batteries, hehe, 3 parallels of 3 in series. then you have 18 volts and more amp/hours... but really, if your gonna do ALL that, and spend the dimes, get a 110v weedeater, they are cheaper and will be way less hassle. way easier to tug a cord around than a bank of batteries... or if mobility/lack of energy is a concern, get a alternator and an engine and run that thing on 14 volts instead.. good luck!

Does the Mule have an alternator? If so put it in neutral and find a way to rig a high idle switch to keep the juice up and run it off of that.

If the voltage is too low than go looking for a 12v model of saw.