4 cell batteries

[tramcar trev]

I have been playing around with my steam tram yet again. I made up a battery pack using 18650 cells and it runs superbly but because I wish to retain my smoke at all costs I dont get much of a run before recharging is needed. Looked around and found these; http://www.hobbyking.com/hobbyking/store/__24624__ZIPPY_Compact_2700mAh_4S_25C_Lipo_Pack_AU_Warehouse_.html
They are not protected but they do have a lead for balance charging. I thought if I increased the voltage I may be able to get away with less current draw and I can but I will have to rewind the heater for the smoke maker or run it through a speed control to give me proportional smoke. I can't find a 4 cell speed controler without brake but with reverse so I'll continue to use the elcheapo 3 cell one, as I'm drawing 2 amps maybe I'll get away with it long term... I also have to up the resistors for the led lighting the 14V makes them too bright and to save having to plug in the jumper lead between motor and trailer I'm going to install a single elcheapo 16850 cell for the trailer lights, just as easy to put them in a holder; http://www.ebay.com.au/itm/Plastic-Battery-Storage-Case-Box-Holder-for-1-x-18650-Black-with-6-Wire-Leads-/360502586215?pt=AU_Electronics_Batteries_Chargers&hash=item53efa0eb67 and use a charger; http://www.ebay.com.au/itm/18650-14500-CR123A-16340-17650-3-7V-Li-ion-Battery-Universal-Charger-/351163008133?pt=AU_Electronics_Batteries_Chargers&var=&hash=item51c2f24485 They seem to hold their charge very well and I think with an 80 mA load are going to last for a year between charges...

 

[GAP]

Trev,

Just chucked one of these in my Bachmann 3 truck shay, works really well.

https://www.dimensionengineering.com/products/syren10

This 4S Lipo @ 14.8V battery http://www.hobbyking.com/hobbyking/store/__15521__Turnigy_5000mAh_4S1P_14_8v_20C_hardcase_pack.html

This charger
http://www.hobbyking.com/hobbyking/store/__7028__Turnigy_Accucel_6_50W_6A_Balancer_Charger_w_Accessories.html

Battery and charger from the Aust warehouse in Moruya just down the road.

The motor controller is a bit expensive at $60 but so easy to install almost plug & play and 10A so it drives the 3 motors in the shay without breaking into a sweat.

A mechatronics engineer put me on to it, but he uses them in fighting robots.

Only downside was that I could not get directional lighting so I used one of these.

https://www.dimensionengineering.com/products/doubleswitch

Again not perfect it switches to NC when I take the throttle to neutral which turns on the rear light, the front light only switches on when the throttle is opened.

Requires more work in own time, go on!!

 

[tramcar trev]

I have a balance charger... The speed control looks interesting but may be Physically to large to fit.
For directional lighting did you try taking the power off from the motor side of the speed control with a diode and a cap (2200uf to smooth out the pulses) as the polarity changes the leds either turn on or off.... I'll try and find the circuit it was in a RC modeling mag....

 

[GAP]

I have a balance charger... The speed control looks interesting but may be Physically to large to fit.
For directional lighting did you try taking the power off from the motor side of the speed control with a diode and a cap (2200uf to smooth out the pulses) as the polarity changes the leds either turn on or off.... I'll try and find the circuit it was in a RC modeling mag....


I did have the LEDs across the motor terminals like I do with all my other stuff but for some reason they stayed on all the time even when the motor was stopped.

the OEM told me that I could not do that and the relay was the way to go.

Will still play with it in the future when I get one of those round touits.

This is the weird bit, I measured 12V across the terminals and the motor was not moving.

I can only assume that the controller is a current control device but from everything I have learned V across R = current flow.

The controller is only 57x35x14mm it fits inside the coal bunker of my shay along with a Rx and the relay, takes up hardly any room( less that my hobbyking setup) and all controlled from one throttle lever.

Up= Fwd, centre = stopped, Down= Rev or the other way around depending on the throttle polarity switch.

 

[tramcar trev]

Leds across the motor will only work with Pulse width modulation.... The elcheapo HK one I have is 0V at centre, move the throttle either way and there is supply voltage.... I'll try and find the circuit....