By Randy Mower

Author  Bio Making battery packs for onboard radio control is easier than you think.

Making battery packs for onboard radio control is easier than you think. Battery packs can be made as big or as small as space allows. When selecting batteries use the largest size that you can physically fit in the area you have. Precise dimensions for different sizes of batteries can be found in my previous article on batteries.

The next consideration is to purchase an amp hour rating large enough to give you the performance you want. Large engines with multiple motors will draw more power so the larger the amp hour rating the longer your engine will run. NiMh batteries will usually have a higher amp hour rating than NiCad batteries of the same size.

I needed to make a battery pack for my Hartland rail bus that would fit in the cargo area along with the sound card, and onboard receiver. You will find that the procedures I used in this article can be applied to any size battery pack.

Rechargeable batteries are rated to provide a nominal output of 1.2 volts. Depending on the power consumption of your engine, the gearing and types of motors select a voltage that will allow you to operate at the speed you want. I use 14.4-volt packs in all my large-scale battery applications because I find that it is sufficient to operate my trains in excess of the speeds I like to operate at.

If you want to run high speed passenger trains or intermodal hotshots you may want to add more batteries to make up a pack with more voltage. In this particular application I used NiMh batteries with a 1700 MAh (milliamp hour) rating since I was only powering a rail bus with a single power truck and it would not be pulling anything behind it so 1700 MAh will run it for a considerable amount of time. If you are installing batteries in a locomotive that will be pulling cars go for 2500-3000 MAh batteries to allow for a long run time.