Hi,
I wired up my NCE PowerCab with an 1156 automotive bulb in series with the track power. What I found is that if I short across the track, the PowerCab shuts down before the light bulb turns on. I can get the bulb to turn on instead if I put about 6 Ohms across the track instead of a dead short. I’m guessing that this is because the inrush current of the light bulb is too big. Has anyone solved this for the PowerCab? I’m thinking about trying a smaller bulb like an 1141.
Thanks,
Jim
The light bulb will not prevent a short circuit, it just indicates when you have one and helps delay the DCC system’s shutting down. If you don’t remove the short, the system circuit breaker will eventually trip.
My first thought was that you may have a defective bulb with a broken or burned out filament, but if it was your track would have no power at all.
I use a 12 Volt, 50 Watt Halogen spotlight as the overload indicator with my NCE ProCab wireless system because it can carry a heavy load, and it glows brightly if there’s a short, but if the short is not removed promptly the main power booster will shut down.
From what I have been able to find on the Internet, there are two types of 1156 bulbs – normal incandescent and Halogen. Which type do you have? A Halogen bulb normally has two pins on the back, but I have found that it is extremely difficult to solder directly to the pins so I always use a socket. A poor solder joint on the pins will pass enough current for the train to operate, but not enough to light the bulb is there is a short.
This response must be unique to the system in question, because I have four such bulbs installed in series between the main bus and a sub for each of my isolated “districts” (unboosted). In every case where the wiring is correct and a short of any nature occurs, the lights blaze and the Digitrax DB 150 maintains power to the tracks to continue ops for the other locomotives in other districts.
Perhaps there is an adjustable delay for tripping to let the bulb do its, thing (?), although the bulb should offer resistance immediately/
I’ll follow this thread so that I may learn something.
The delay setting was a good idea, but I couldn’t find one in the powercab setup.
Jim
I think that you just listed the reason that the 1156 bulb does not work. The 1156 limits the current to “about” 2 amps. There would be a larger inrush before the bulb actually lights up. I use the 1156 bulbs with my Prodigy Advance and the system works great.
I really question light bulb usage with a “small” system like the 2 amp Power Cab. You need something that will limit current to a short and still let another engine run. This would require many blocks (only one train per block) = all with current limited to about one amp. NCE does make a 1 amp, four light bulb, system that might work fine for your use.
The PowerCab puts out about 1.7 amps. The 1156 bulb will limit you to about 2.5 amps. The 1156 never sees full amperage and will not provide any usefull current limiting. If you had a 5 amp booster, then it would limit current to 2.5 amps…
Jim