The Signaling Solution
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4th Dimension Engineering, LLC
PO Box 384
Datil, New Mexico 87821

812-533-1047 (voice, 10-4 mst)
708-570-6140 (fax)

BD8 Block Occupancy Detector

The BD8 Block Occupancy Detector is a state of the art train detection system which has the following features:

Detects trains in up to 8 separate blocks, up to 3 amps/block.
Works with DCC (Digital Command Control), DC or AC train power.
Provides occupancy detection for ABS, APB & CTC signaling when used with our separate MSC Master Signal Controller boards. No computer or software required.
Provides OCCUPIED and VACANT outputs for each block.
Can detect any engine or rolling stock that draws at least 200 microamps.
Detects by monitoring current to each block.
Operates LED's using the on-board regulated 5 volt supply and external current limiting resistors.
Provides occupancy detection for computerized layouts. Requires separate computer interface board.
Can also operate bulbs, relays to output logic signals to other circuitry.
Outputs can switch 200 milliamps at up to 16 volts DC.
Furnished completely assembled, with mounting hardware.
Built in self-test functions to assist in installation and trouble shooting.
Download user's manual at no cost.
Requires a 12 VDC regulated power supply that can be shared by numerous other circuit boards.
Copyright 1998-2021 4th Dimension Engineering, LLC
Last update: December 28, 2021