SSL (Simple Signal Logic)‏
{"Image DocumentName": "SSL (Simple Signal Logic)\u200f", "Image ImageDescription": "SSL basics. ABS defaults to Clear signals, and drops to Stop if the block immediately beyond the signal is occupied, or if the switch (turnout) beyond the signal is set against the direction of traffic. Therefore ABS requires input information for track occupancy and for switch position. ABS also shows a limited speed indication called Approach if the next signal beyond this signal is showing Stop . This is a warning to the train crew to approach the next signal prepared to Stop before they reach it. If the signals are close, or trains long, some systems would give a double warning using a flashing signal.", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}