Hello, I picked up a 0-3A ammeter and wired it in-line between my power pack and the RR track. It works fine in one direction, but when I throw the Reverse Switch on the power pack the ammeter zero's out. Anyone know any wiring tricks to get around this problem? Thanks in advance. Mike
You would need a center zeroing ammeter to hook it up after the direction switch. You could open the power pack and wire up the meter in series before the direction switch.
You could put a direction switch (double pole double throw) after the amp meter and not use the one on the power supply. I think atlas may sell them for railroad stuff or go to radio shack and get one.
There is a way to do this. You need an internet search with the appropriate terms. The meter you have is fine and the wiring is simple to make it work regardless of track current polarity. More as I find it. IIRC, this solution is in the old NTrak Electrical How To book.
Simple solution: Get a bridge rectifier from your local electronics store. Wire the + terminal to the + side of the meter, the - terminal to the - side. Connect the ac (~) terminals in-line where the meter itself used to be. No matter the polarity output of your power pack, the diodes in the bridge will route the current in the proper direction for the meter.
Just be aware that you will lose about 1.5 volts off your controller with this. Ie. you'll have to turn it up to 1.5V before any current will flow and the max speed will be 1.5V lower. Not usually a problem unless you run Acelas at scale speed
