buzzer emitting a low level tone

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I began wiring my bus today, and within 10 feeder connections, I began to get a very low level tone from the beeper. It is nothing like the tone you get with a full short, but it is clear I have current leakage. I isolated a section of track, and it appears I have current leakage between the rails. There is nothing connected, nothing floating under the rails, the rails are spiked on wooden ties glued to homasote. For the life of me, I can't figure this out. I measure 180K ohms between the rails, but the value climbs, almost like there is some capacitance. The more rail I connect, the lower the resistance goes. Anyone seen this before? I'm beginning to think the current is passing through the ties. Is that possible? I sure didn't think so.

-- John Hartline (hartlinej@direcway.com), October 24, 2004

Answers

John,

Since you said you added more track and the problem got worse, it does sound like you are getting something through your ties. I presume you don't have any locos on the track or any boosters connected when using the buzzer. I agree with Dale.

I just want to add one point. A resistance of 1k or more will not cause you any problems. I use 2 10k resistors on EACH of my cars for block detection. All these cars don't put a significant load on the booster.

So keep using your buzzer. Keep an eye on the resistance situation. But as long as you don't develop an actual short, don't loose any sleep over high resistance. I agree with Dale and think your Homasote has absorbed some water. This may go away in time.

-- Allan Gartner (wire4dcc_admin@comcast.net), October 26, 2004.


John,

There is one more thing to be sure you don't have hooked up. That is stationary address decoders (turnout and signalling controllers.) They are easy to forget if you have them.

Otherwise, keep wiring happily along! :)

Allan

-- Allan Gartner (wire4dcc_admin@comcast.net), October 26, 2004.


John,

there could be current leakage through the ties. Has the track been ballasted? Did you use a water based ballasting method? Do you live in a high humidity area? A little water may take a long time to dry and would cause what you are seeing.

Dale Gloer

-- Dale Gloer (dale.gloer@telus.net), October 26, 2004.


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