If your PS315 is only rated a 3 amps it is probably too small for your train. My Lionel LW is rated for 6 amps and average size trains with PW lighted passenger cars often draw more that 3 amps output.
I know this as I have a Amprobe clip on ammeter that I can connect to any of 3 Lionel LWs transformers and measure what amps a train is pulling. I have had the ammeter for 30 plus years and it is rated for 25 amps. I use is check the draw of appliances around the house and shop. It has an adapter that lets you plug in the cord of item into and read the amps without cutting wires.
The Amprobe amp meter has a small area to show the 0 to 5 amp range and is hard to read. To amplify this area to 5 times its size I made a simple 5 loop wire donut that changes the max reading from 25 amp max to max of 5 amps. With a clip on ammeter I only need one meter and can move it to each LW . They all have a 5 coil donuts.
Picture of $25 Amprobe Clamp on Ammeter, note the compressed area of 0 to 5 amps on the left of the scale.
Picture of 5 turn coil, LW transformer and Amprobe clip on ammeter, reading scale for 5 turn coil in service are the big numbers added on with tape.
A Amprobe clamp on ammeter would be useful all over the shop and house, uses no batteries and does not need to be hard wired in.
Charlie
