on Wed Aug 1 16:39:37 2012, in response to Re: Wheel detectors, posted by G1Ravage on Wed Aug 1 05:42:52 2012.
I never saws the exact situation you describe. From what I have observed, all wheel detectors flash until the approaching train slows to the required speed at which time it then illuminates steady. If the train should accelerate too fast, the WD light will again flash until the train is slowed to the required speed. Unlike conventional GT signals, the stop arm on a WD signal will come up under a train and trip it on other than the head car if the train should exceed the required speed after the lead car has passed the WD signal.