Installing Grade Crossing Flashing Crossbucks

[mondotrains]

Hi Folks,
I just reviewed the instructions I got with Berkshire Junction's Flashing Grade Crossing Crossbucks and would like some input. The crossbucks contain red LED's which obvioulsy fla***o warn cars that a train is coming.

The unit relies on light sensors being placed between ties. When any one of the 8 sensors (4 in each track of my double-track mainline) are shadowed by an engine or car, the lights start flashing. At first glance, I had planned to install the sensors quite far from the grade crossing to give the autos plenty of warning. However, after thinking about it, I need to accommodate a short train, such as a single Budd car, which is only 12 inches long. In other words, if I place the sensors let's say several feet before the crossing, the lights will begin flashing when a Budd car covers a sensor and the lights will stop flashing before the Budd actually gets to the crossing.

The only answer I can come up with for each of the mainline tracks is to place 2 sensors, one on each side of the crossing, about 12" apart (the length of the Budd cars) which is about 6" on each side of the crossing. Then, I plan to place the other 2 sensors about 12" futher east and west from the first sensors. This will cause the ligths to start flashing when a Budd car comes from east or west and when it is about 18" from the actual grade crossing....or about 2 seconds before the train gets there.

My first question: will this be kind of "hokey"? I know the prototype flashing lights start more than 2 seconds before a train arrives....but that's in real time, not 1/87th HO scale time, if you know what I mean.

I should tell you that Berkshire Junction's crossbucks with 8 sensors to handle a double-track mainline and flashing unit cost $35.00. I've since learned that Circuitron and Tomar Electronics make more sophisticated units that have logic programmed in them such that once a sensor is "tripped", the lights will keep flashing till the shortest or longest train clears the second sensor. Of course, these units cost more; a lot more.

I'm looking for opinions. Is the Berkshire Junction unit fine? I'd like to be convinced that as long as the lights start flashing a couple of seconds before the train arrives and stop flashing a couple of seconds after the train passes through the crossing, is okay.

Any help would be appreciated and thank you in advance.
Mondo

[cacole]

Check the module made by Logic Rail Technologies. Their circuit board allows you to place four sensors as far apart as you need. The first sensor turns the signals on, and they remain on until the train has cleared the two sets nearest to the roadway, indicating that the train has cleared the crossing, before turning off. It will also control a Tortoise switch machine for activating crossing gates. For a double track road crossing, you need two circuit boards. Their circuit board includes everything -- sensors, flashing module, crossing gate motor power, etc. It will work with either photoresistors placed between the rails or infrared emitter/detector pairs aimed across the track. I prefer the IR emitter/detector pairs because the photoresistors require that fairly bright overhead lighting always be on. If you want to simulate night running and turn off the overhead lights, the signals will come on and remain on no matter what you do, because they think the resistors have been covered by a train. I aim the IR emitter diagonally across the track so the inter-car gap doesn't cause false triggering, and also aim them slightly upward so they will work even when a flatcar passes. I use type QEE123 and QSE113 IR high-powered side-looking emitter/detector pairs, which can be placed far enough away from the track to clear all of your rolling stock, yet remain very inconspicuous. These items are very small, black squares that can be made to look like signal boxes.

You can download Logic Rail Technologies installation manual and read through it to help you decide if it is what you're looking for.

[Eriediamond]

Mondo, Ican appreciate your concern about your cross buck flashers. I can only give you an "if " answer here, in that if the 2 second flashing before train arrival suits you and your budget, I would not find fault with that. Something else you may want to consider, is the type of sensors you are going to use. I would suggest, if you are going to be doing any night time running, you may want to think about infra-red sensors or your signals will flash all the time if you turn your lights down too low. Good luck with your project. Ken