Possible battery convert with some questions

[whatlep]

Yet more useful info in the last two posts!

Ross - any supplier links for the Lipo batteries/ charger?

 

[Tony Walsham]

3.4 Amp hour Gel cells are quite big and heavy. I wouldn't use them in a trail car situation anyway because of that. Maybe in a loco, as the weight will aid traction.
Still, voltage is the main determinant. If there isn't enough oomph!! cheapness cannot come into it.

 

[MR SPOCK]

I did try trailed with lead acid and was ok on the flat but on any incline almost hopeless, the extra weight in the locos is good but I would add caution to that, if you use locos wth traction tyres a sudden stall would destroy the gearbox, especially on somethig like an USAT loco

Regarding the sealed lead acid cells, Tony's words are very helpful. It's easy enough in UK to get 12v 3.4mAh lead-acid cells which are cheaper than the equivalent AA cells and - obviously - have a longer nominal run time, but I will have to think about the voltage implications before taking further action. This battery stuff isn't as simple as I expected!

Another thing you may wish to consider is the weight. A lead acid installation is often heavier, this could be an advantage if mounted in a loco and more tractive effort is required but may have an adverse effect run time. If in a trailing car then the extra weight is usually bad news.

​

 

[Doug]

When i built my boxcab diesel i used 4300mAh SubC NiMh batteries, with 9 cells giving 10.5 volts. They cost about £50 for a made up battery pack. They last for about 4 hours running the USA Trains powerblock. The speed controller cost about £60, the sound card £90, plus the cost of the R/C Tx and Rx.

 

[MR SPOCK]

That is really neat ,never thought about using plasticbags for the cards but its so simple and good to keep everything dry and insulated, the whole install looks very well thought out as well its given me some really good ideas, thanks​

 

[Doug]

That is really neat ,never thought about using plasticbags for the cards but its so simple and good to keep everything dry and insulated, the whole install looks very well thought out as well its given me some really good ideas, thanks​

The cards are covered in clear shrink wrap. Stops shorts etc.

 

[MR SPOCK]

Thanks Doug will look for some at work in the stores ooh eck hope the boss not into G​

 

[Del Tapparo]

FYI - My new http://1stclass.mylargescale.com/DelTapparo/RailBoss_Plus.htm < Link To RailBoss Plus 2.4GHZ R/C controller has a built-in low battery warning system for Lithium batteries. Li-Po's will be damaged if discharged below 3.0 V per cell. The RailBoss will provide a hard cutoff to prevent that damage. In addition, it will warn you in advance of a low battery, so you can get the train back to the engine house before either the RailBoss hard cutoff shuts you down, or the safety PCB in your Lithium-Ion battery pack shuts you down. Without this warning, you train will be dead in its tracks and have to be physically carried back to the house! Even if you think you know how much run time you can get from a certain battery pack, this system will let you run trains, not watch the clock. It can be adjusted so that you know you have X minutes of run time left when you get the warning.

 

[Tony Walsham]

Personally I don't think wrapping electronics that can get hot in any sort of wrap is a good idea.
Granted the FET's may not get hot but voltage regulators usually do. Hot enough to melt plastic touching them.
I would mount the ESC's and sound card on a suitably sized sheet of thin styrene with a non metallic Silicone adhesive if you are worried about shorts. Leave the topside components free to the open air to aid cooling.

 

[Madman]

Tony, that's a new one for me, "Non metallic silicone adhesive". I had no clue that there was some sort of metal in silicone. I know that many years ago there was a story floating around about a family being sickened from a silicone sealant repair to their dishwasher, due to the arsenic content in the silicone. I'm not sure if the arsenic has been deleted from silicone caulking.

Please excuse any spelling mistakes

 

[Madman]

When i built my boxcab diesel i used 4300mAh SubC NiMh batteries, with 9 cells giving 10.5 volts. They cost about £50 for a made up battery pack. They last for about 4 hours running the USA Trains powerblock. The speed controller cost about £60, the sound card £90, plus the cost of the R/C Tx and Rx.

Doug, that's are very nice box cab indeed. I see a skate sticking out of the bottom between the wheels. Did you use an LGB motor block. The chassis looks something like a Hartland chassis, is it? Again, I really like it.

 

[Tony Walsham]

New to me to Dan.
But, nevertheless apparently there is. Which may of course short out the connections on the back of the pcb's.
I use a local brand, Selleys roof and gutter sealant. I have never had a problem with it.

 

[Doug]

When i built my boxcab diesel i used 4300mAh SubC NiMh batteries, with 9 cells giving 10.5 volts. They cost about £50 for a made up battery pack. They last for about 4 hours running the USA Trains powerblock. The speed controller cost about £60, the sound card £90, plus the cost of the R/C Tx and Rx.

Doug, that's are very nice box cab indeed. I see a skate sticking out of the bottom between the wheels. Did you use an LGB motor block. The chassis looks something like a Hartland chassis, is it? Again, I really like it.

Its a USA Trains motorblock, see the Boxcab thread under scratchbuilding for the full story

 

[Doug]

Personally I don't think wrapping electronics that can get hot in any sort of wrap is a good idea.
Granted the FET's may not get hot but voltage regulators usually do. Hot enough to melt plastic touching them.
I would mount the ESC's and sound card on a suitably sized sheet of thin styrene with a non metallic Silicone adhesive if you are worried about shorts. Leave the topside components free to the open air to aid cooling.

The electronic speed controller board only gets vaguely warm when running at 1amp. The ESC is rated at 5 amps without the need for a heatsink. The 2nd board is the soundcard that doesn't get hot at all.