I have recently purchased two Proto 2000 engines with QSi sound. I have heard the start voltage is high. What should I set it for. I have played with 14, 28 and 128 speed steps and various voltages. It seems the higher the voltage the better. The manual is vague in regards to this. Any thoughts on this would be appreciated.
On DCC, the way it comes is fine unless you want to match it to the speed of another engine. The high start voltage reffers to operation on DC. DCC voltage is constant.
A new engine is almost certain to need a higher start voltage than when it is finally broken in…if my BLI experience is anything to go by. CV 2 can be set for any value between 0 and 255 on all decoders that I use. The nominal value at the factory will usually be near 37, maybe a bit higher.
Until the loco is well broken in, just crank up the juice on the knob until it moves as you would like it to. Later, after a couple of hours pulling a train in each direction, place the loco on a track by itself, and start programming in CV 2 values until it just begins to crawl on a dial/display setting of “1” for speed. That value is your start voltage value.
If you are talking about the high inrush current to get the sound system to activate, that is a common function of QSI decoders and their capacitor. I don’t think that can be adjusted, but I could be wrong.
Start voltage under DC is high for the sound units because, well, you have to power the sound circuit. This is NOT the same thing as saying the start voltage on a lower-quality locomotive is high and it leaps into action at 20 scale miles per hour from a dead stop. The P2Ks will run very nice and slow, it’s just that they won;t start to move slowly until the throttle is halfway up because of the sound circuitry. The downside is reduced control range - you have only say half the throttle motion from a crawl to full speed vs the same loco without sound.
With DCC, it’s not a problem. The track always as power, so the sound system is always up and running. Properly adjusted, they should start creeping along at speed step 1. I think the P2K sound units, like the Atlas ones, have QSI’s Regulated Throttle Control enabled (basically, Back-EMF) whereas BLI’s do not. The single coolest thing you can do under DCC is program in some start and stop momentum so you can crank the throttle and hear the engine “load up” while merely creeping.
–Randy