More voltage in Power functions?

[Solscud007]

hey guys, perhaps you more experienced guys might now this answer.

So I added power functions 88000, 88002 motor, 8870 light, and 8884 I receiver to my wifes christmas train. The 6xAAA are too weak to power the light and run the train motor. You can see the lights dim and the train slowly chugs along. It runs a smidgen better if the lights are off.

I also recently got the Motorized Star wars Lego ATAT. It uses the 8881 Power Box. The 6xAA batteries are a little underwhelming.

A part of my hobbies is flashlights. To get more light out of LEDs we can over drive them with rechargeable li-ion batteries.

There is a battery called a 14500. It is the same physical size of a AA but it is 3.7 volts. 4.2 volts hot off the charger.

I was wondering if I ran 3 of these in the 8881 power box with 4 dummy AA spacers, theoretically it will be 11.1 volts. Would this burn out the motor? Has any one tried running more voltage thru these power functions?

Also does the 8882 XL motor have more torque than the 8883 M motor?

Edited December 24, 2011 by Solscud007

[barti673]

hey guys, perhaps you more experienced guys might now this answer.

So I added power functions 88000, 88002 motor, 8870 light, and 8884 I receiver to my wifes christmas train. The 6xAAA are too weak to power the light and run the train motor. You can see the lights dim and the train slowly chugs along. It runs a smidgen better if the lights are off.

I also recently got the Motorized Star wars Lego ATAT. It uses the 8881 Power Box. The 6xAA batteries are a little underwhelming.

A part of my hobbies is flashlights. To get more light out of LEDs we can over drive them with rechargeable li-ion batteries.

There is a battery called a 14500. It is the same physical size of a AA but it is 3.7 volts. 4.2 volts hot off the charger.

I was wondering if I ran 3 of these in the 8881 power box with 4 dummy AA spacers, theoretically it will be 11.1 volts. Would this burn out the motor? Has any one tried running more voltage thru these power functions?

Also does the 8882 XL motor have more torque than the 8883 M motor?

You could always buy another b-box, the normal b-boxes are very cheap now.

And yes it have extreme torque, which can even break your parts! :]

Edited December 24, 2011 by barti673

[aposaric]

I think that 11 Volt current will shorten the life of your motors. One of my hobbies is also making LED lights, for night cycling and skiing, and I found the cheapest way to power them is to use LiPo cellphone batteries, I use sonyericsson 3.2 volt cells, they are just few grams heavy, and they have 950mA/H capacity, so they can power 3w cree LED for around 1,5 hours on full blast. And they are easily rechargable, you just plug them in your cellphone while you are drinking on a top of the hill, before the night slope. You could put 3 of them in series ( but be carefull with LiPo, they have to be exactly the same, same line, same type, same speed of discharging, otherwise they can even explode, if not handeled priperly ) so you will get 9,6 V current, which is still on a safe side, and you will get the realy great boost in performance. Lego rechargable box works on less then 8 volts, so you will be able to see the difference in performance :-)

Cheers,

andrija

[DLuders]

@ Solscud007: Rien posted his test results of using an 11.1-volt LiPo battery in his Power Functions creation, with (apparently) no ill effects: http://www.eurobricks.com/forum/index.php?showtopic=59506&st=0&p=1061034&hl=volt&fromsearch=1entry1061034 . On that post, there was extensive back-and-forth pros/cons of using this setup. If I were you, I WOULD TRY using three of the 3.7-volt batteries to power your train!

In regards to your question about motor torque, you will enjoy reading Philo's excellent "LEGO 9V Technic Motors Compared Characteristics" and "LEGO Train Motors Comparison" articles. Yes, the 8882 Power Functions XL motor has roughly twice the torque (but ~half the speed) of an 8883 PF Medium Motor, but that varies with voltage as shown on Philo's graphs.

Edited December 24, 2011 by DLuders

[aposaric]

WOW, so there should be no harm to the motors if I power them on 11 V? I have to try it on some truck, I could benefit from more speed now and then :-)

Edited December 24, 2011 by aposaric