I made a 'short detection buzzer' from an article on DCC wiring and it said to be sure the booster/command station is NOT connected to your track when using the buzzer. It is basically a piezo buzzer from Radio Shack and a 9vdc battery connected with a pair of alligator clips to connect to the rails. I disconnected all my power from the track, which has been running fine even before I recently (2-3 months ago) converted to DCC. Almost every section of track on my layout sets the buzzer off. Only one area that has been isolated for a previous block didn't 'buzz'. The article said that this was the first thing one should build and use when wiring a layout for DCC (or even DC) as it will immediately let you know if you have a short in the track wiring. I don't have my buss connected to the track yet, so all the electrical 'flow' is thru the rails. If I have so many 'shorts' all over my layout, would it still be running? Do any of you use this 'buzzer' when wiring your layout? Also, I have about 9-10 locos on the tracks; would this cause the buzzer to go off? Any suggestions about this procedure would be appreciated.
Bob
Life is what happens while you are making other plans!
I started building my present layout seven years ago and wired it for DCC even though I was still using DC. I switched to DCC five years ago. I just hooked up the command station (Digitrax Super Empire Builder) and ran. The command station will tell you if there is a short. I would replace the buzzer with a test light (automobile tail light) with the battery and try again. I don't trust anything but a test light. Does the layout work on DC? Yes any loco's or lighted passenger cars or caboose's on the track will make the buzzer Buzz.. So take all of them off the track and try again.
farrellaa Also, I have about 9-10 locos on the tracks; would this cause the buzzer to go off? Any suggestions about this procedure would be appreciated.
Also, I have about 9-10 locos on the tracks; would this cause the buzzer to go off? Any suggestions about this procedure would be appreciated.
Bob,
Take the loco's off the track if you want to test your buzzer. I think you have already found out it works because it sounds when you have a short (loco across rails). Doesn't sound when you test that one isolated block.
Martin Myers
Thanks guys, I will remove all rolling stock from the layout and try again.
Did you disconnect the DCC system from the track before you attached the 'buzzer'? I suspect you are looping back through the DCC system. A 'buzzer' or 'test light' is a great addition to your problem determination tools. A cheap multi-meter dedicated to your layout also can come in quite handy.
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
I built one when I started using DCC and the promptly never used it. Haven't had to rewire a feeder yet. I use two different color feeder wires, and matching bus wires, so I always connect red to red, white to white. Also when installing the feeders I am careful to make sure each one is on the correct rail. Since my current layout is around the walls, I simply remember "red to the rear" to kee things straight. It makes it obvious when wiring a reverse loop, as well. If I had a reverse loop, sudeently the rail that I had been connecting the red feeders to would need a white feeder to maintaint he same mnemonic. oops. Sort of like taking the track plan and tracing each rail in a different color, if the two colors touch anywhere - you have a reverse loop.
Everything across the rails needs to be removed for a buzzer to work in this manner - the DCC system (since it could be damaged) and anything that can conduct, even if not a dead short - lighted cars, locos, etc.. A buzzer rated at 9V, with a 9V battery, will make noise starting well below 9V gettign through, so even the resistence of a loco motor will likely still allow the bizzer to sound - better locos will even take off under such conditions.
The whole idea of using a buzzer works for simple layouts - disconnect the DCC system, attach the buzzer to the bus wires. If you wire a feeder to the wrong bus wire, it will create a short and set off the buzzer. If you have downstream detection systems, or have track power LEDs wired in, all bets are off.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I use my trains for short detection. When they stop running I have a short
Springfield PA