Sigma BM-286A service manual Theory of Operation, Unit Operation

4. THEORY OF OPERATION page 28

4. THEORY OF OPERATION

The BM-286A system is a self-contained Bag/Box monitor, operated by two personal computers.

4.1. UNIT OPERATION

The main computer operates in Windows NT, with a touch screen, color LCD display to monitor system operation. The system can be used with an external keyboard for operator input, and a printer to generate reports, or labels. Operating parameters can be entered from the touch screen or external keyboard via a password protected set-up menu.

The DOS based computer has a TSA Systems custom counter card and sends information to the NT machine every second via RS-232. The output consists of the door position and six detector counts.

The NT system continually monitors the serial data for fault conditions, and displays any errors on the computer monitor. If the system detects a fault condition, it will not allow normal operation until the fault condition is corrected.

4.2.COMPONENTS

4.2.1.Component Locations:

Refer to "BM-286A Pictorial View" Drawing 1 and "BM-286A Pictorial View (Door Open)" Drawing 2 (Appendix F.).

Six plastic scintillation detectors, their associated photo-multiplier tubes, voltage divider assemblies, and, optionally, a Sodium Iodide detector are contained within the walls and door of the main assembly. A slide out platform contains a third party weight scale. The scale controller is located in the top of the unit with the other electronics.

Model BM-286A