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To: "oermsignal" Subject: Orange Empire Railway Museum Signals Update - 4/19/2004 This email is our semi-regular update about signals work (installation, maintenance and restoration) at the Orange Empire Railway Museum and is a collaborative effort -- the information for this e-news issue was provided by Allen Holliday and Gene Cranston. If you have information that would be of interest to others, please email it to me and we'll include it in our next newsletter. If you would like to be removed from this mailing list, please email me. Likewise, if you know someone who would like to be added to this list, please have them email me. If you receive duplicate copies of this email, please contact me and let me know your preferred email address. ------------------------------------------------------------------------------------------- 11th St. Crossing - the saga continues: Gene thought 11th St. was fixed with the broken bonds welded and the AFTAC replaced last Sunday BUT just before 11pm last Sunday night (8 days ago), he got a call from the sheriff. The crossing was starting on its own about every minute or so. Gene got out of bed and was at the crossing in about 15 minutes. The lights would go on and the gates start down every minute or so with the approach track relay dropping and operating for about 7 seconds. At the receiver location the track repeater relay would drop for about half a second and of course the reverse repeater (loss of shunt circuit) would keep the circuit open for 7 seconds. He disabled the entire crossing that evening -- planning to return with a crew of very observant people to look for a broken rail, bad track wire connection, trail of salt or whatever and possibly make voltage measurements every rail length to pin point the location - if it would just stay failed long enough. As background on the design of the crossing, the circuit is one long approach track circuit with an island overlay in the middle. The approach circuit is a Harmon AFTAC and the island is a Marquart Island audio frequency overlay. The island has given no problem so far but the AFTAC goes down for about half a second every minute or so. The power at the transmitter is a battery floating on a regulated power supply as a charger. This past Friday, Gene, Mike and Allen spent most of the day working on this crossing trying to fix the phantom train problem. They measured voltages and looked for missing bonds or other track problems. Mike was at the south transmitter and he tried disconnecting the impedance bond. When he did, the voltage jumped markedly -- from around 0.8 to 1.8. They re-enabled the crossing and tested it with a test shunt at the north case. The gates seemed to work fine -- they went down when they should and didn't otherwise. However, the original problem only occurred late at night (about 11:00), so they were suspecting some temperature-related condition. Gene added a capacitor and resistor to make the relay a slow-release (the track relay is delayed to hide any "glitches" shorter than 3 seconds from the crossing circuits). They also hooked up a strip-chart recorder to see if the relay drops overnight. Gene checked the recorder tape Saturday morning --- there was no spurious operation. lt started to rain so he turned the recorder back on to see if the rain might cause a malfunction. He rechecked the tape Sunday morning which showed that all day Saturday the track shunted well with no sign of improper operation. Operation all day Sunday was perfect. We'll now wait and see. Telephone Repair: Mike and Allen also worked on a crank phone problem between the bookstore and Barn 1. They found a bad splice but that wasn't the problem. Mike is going to replace the overhead wire and check some other splices, sometime this coming week. Festival Preparation: Everything seems to be ready for Rail Festival (April 24 and 25 at OERM) except that the temporary flasher still needs to be finished (this has been delayed due to all of the panics out at 11th St). Gene hopes to work on it during this coming week (possibly Wednesday or Thursday - April 21/22). If you can help Gene with the Flasher this week, contact him to coordinate. -------------------------------------------------------------------------------------------- For additional OERM Signals information, visit the signals website at: http://gsee.sdf-us.org/signals. Previous editions of these email newsletters are at: http://gsee.sdf-us.org/signals/enews/enews.html . Questions or comments regarding OERM Signals should be directed to the Signals Superintendent Gene Cranston. |