Electrical Question

[Anonymous]

I just completed the layout of my garden railway, and noticed something strange in the way my 2-truck deisel engines run. The moment the front truck of the engine crosses from one electrical block to the next, it momentarily speeds up, as if it gets a surge of voltage. Once the rear truck crosses to the next block, the speed goes back to normal. Any idea what causes this jerky action? I'm new to this, and I may have my layout wired incorrectly. Thanks

[cacole]

If you had the layout wired incorrectly, the locomotive would stall at the block boundary. Are you using two different power packs for those two blocks, and do you have momentum turned on? It sounds like a second power pack, even though set at the same speed, has had time to fully charge its momentum capacitor, and is therefore feeding a higher voltage to the track at the juncture of the two blocks. Shortly after the locomotive enters the second block, the current draw on the second power pack partly discharges the capacitor and lowers the voltage, slowing the locomotive back down.

Three possible solutions to the problem, in order of likelihood: First, turn off momentum on your power packs if you have that feature turned on; second, you may need power packs with a higher wattage output, because current draw causing a locomotive to slow down is indicative of inadequate power being fed to the track; and third, you're using too small a gauge of wire between the power pack and track. You should be using something like outdoor low-voltage light wire between the power pack(s) and track. Stranded wire of 14-18 gauge is preferable over solid wire, and it must be weatherproof wire that is rated for outdoor use.

[Anonymous]

I think what Cacole had to say makes alot of sense and as i do not use block wiring myself, its hard for me to comment.

If that doesn't work consider the full load to no load ratio of your power supplies.Most of these train power supplies that i have seen have lousy no load to full load regulation and as you cross between the blocks; you are only half loading 2 power supplies and therefore the voltage on both will rise and give you your surge.

regards


Ian

[Anonymous]

Thank you for the suggestions. I will try them this weekend, and let you know the results. I am using an AristoCraft 5460 10Amp Transformer coupled with 5401 & 5401-10 controllers. I believe that the 5401-10 controller has momntum built in, but an unsure how to turn it off. Thanks again for the suggestions.
Tim