using different voltage batteries in cordless tools

[skinee]

i have recently bought an 18v panasonic drill and jigsaw,i already owned the panasonic 14.4v impact and sds drills and am wondering if (as the batteries fit in all of the tools) it is safe or advisable(for the tool)to swap them around if the need arose,for example using the 18v battery in the 14.4 impact drill or vice versa,i guess this question would also apply to the festool range as the batteries will fit in all tools.

 

[Ken Nagrod]

Just a general warning.  You could probably use a lower voltage battery in a higher voltage tool as long as the batteries physically interchange (like the Festool drills), but never the other way, using higher voltage battery than what the tool specifies as you will likely do damage to the tool's motor.  Always consult the tool manufacturer's instructions and recommendations or contact them directly for advice.  Your warranty and tool may depend on it.

By the way, if you don't take my advice ( and that's ok ) and burn out the motor, post the pictures for others please.

 

[jmbfestool]

If the batteries fit it should be perfectly fine to use.  I'm pretty sure Panasonic would of altered something slightly on the batteries so they won't clip into place if your not suppose to use them with other tools.

Like milwuakee do 18v. 1.5ah batteries and 18v 3.0ah batteries same voltage but you can't use the 1.5ah on a lot of the 18v range like the circular saw, SDS, Grinder   Because they have a small lug which won't let the battery clip into place.  Same with festool they have a longer lug on the 18v batteries so they wont fit on some of the tools 14.4v only.

Jmb

 

[Ken Nagrod]

JMB,

The Milwaukee tools you're referring to would draw too much current from the lower Amp hour batteries damaging them.  That's why they have that safety and written warning in place.  You can't just throw any battery on any tool just because it fits.  Should I dare you?  It's your money.

 

[skinee]

thanks for the replies,i just wonder at times if the motor on an 18v tool is really the same as one on a 14v tool and the only difference being the run time due to the extra cells in the 18v,i'm guessing those dc motors would have some tolerance and work within a certain variation of voltage,perhaps someone with a knowledge of electronics/dc motors could say?

 

[Ken Nagrod]

Not the same motor.

 

[Brice Burrell]

JMB,

The Milwaukee tools you're referring to would draw too much current from the lower Amp hour batteries damaging them.  That's why they have that safety and written warning in place.  You can't just throw any battery on any tool just because it fits.  Should I dare you?  It's your money.

JMB, I double dog dare you. [tongue]

 

[AlexThePalex]

thanks for the replies,i just wonder at times if the motor on an 18v tool is really the same as one on a 14v tool and the only difference being the run time due to the extra cells in the 18v,i'm guessing those dc motors would have some tolerance and work within a certain variation of voltage,perhaps someone with a knowledge of electronics/dc motors could say?

As Ken said, they are not the same motors. You are right when you say that motors have some tolerance in the voltage they work with. Every motor is designed to work with a specific optimal voltage in mind, but, within certain limits, will work with other voltages too. It depends on how the motor is designed. Some will work with a wide variety of voltages, others will not tolerate more than ±0.5v. 

Going to a lower voltage is mostly not a problem for the motor in the sense that it can be damaged. It will still work, but at a lower speed and with less force. At some point the motor will simply not work anymore because the voltage is too low to overcome the internal friction of the motor.

Going to a higher voltage is more dangerous and can easily destroy the motor. Heat is the biggest problem. The motor runs at a faster speed which generates more heat and its casing is not designed to dissipate all this extra heat. The internal electric wiring of the motor is also not up to specs for the higher current, also resulting in more heat generation. It is possible the copper wires simply melt.

 

[Kev]

JMB,

The Milwaukee tools you're referring to would draw too much current from the lower Amp hour batteries damaging them.  That's why they have that safety and written warning in place.  You can't just throw any battery on any tool just because it fits.  Should I dare you?  It's your money.

JMB, I double dog dare you. [tongue]

What the heck - why don't you just plug it into the mains ... if you blow your arm of, you've still got one spare  [cool]

 

[skinee]

panasonic now seem to be bringing out a range of dual voltage tools 18v/14.4v,both voltages can be used and the new 18v battery has in increased capacity of 4.2Ah
http://www.dm-tools.co.uk/product.php/section/9905/sn/PANEY78A1LS1G31

 

[Alan m]

panasonic now seem to be bringing out a range of dual voltage tools 18v/14.4v,both voltages can be used and the new 18v battery has in increased capacity of 4.2Ah
http://www.dm-tools.co.uk/product.php/section/9905/sn/PANEY78A1LS1G31

i got that email as well.
its pritty cool. not gone on the looks but power wise its great.
4.2 ah when will they stop.
my 2ah dewalt batteries are getting bet  and will need replacing soon. i am planing on getting 4 ah . when are they going 5 or 6 ah. next year maybe

 

[Stone Message]

Hi Alan

I use Hitachi cordless drills - bought my first in 1987 and it was only ever battery failure that caused me to replace any of the set. I recently did a couple of reviews of several drills in their 18 Volt 4Ah range, including a brushless motor machine. They were all really nice with excellent chucks - it was such a shame to have to return them.

Peter