Search NASASearch

SEARCH · Search NASA

Results for “rtu”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

Remote Monitor Alarm System

A remote monitor alarm system monitors discrete alarm and analog power supply voltage conditions at remotely located communications terminal equipment. A central monitoring unit (CMU) is connected via serial data links to each of a plurality of remote terminal units (RTUS) that monitor the alarm and power supply conditions of the remote terminal equipment. Each RTU can monitor and store condition information of both discrete alarm points and analog power supply voltage points in its associated communications terminal equipment. The stored alarm information is periodically transmitted to the CMU in response to sequential polling of the RTUS. The number of monitored alarm inputs and permissible voltage ranges for the analog inputs can be remotely configured at the CMU and downloaded into programmable memory at each RTU. The CMU includes a video display, a hard disk memory, a line printer and an audio alarm for communicating and storing the alarm information received from each RTU.

Stute, Robert A.

SCADA Application for ACTS Technology

A satellite and earth terminal systems study was initiated by the NASA Advanced Communication Technology Satellite (ACTS) Project Office and was performed by Hughes Network Systems. The purpose of the study was to investigate the potential of a specialized Ka-band spot beam satellite to reduce the cost of supervisory control and data acquisition (SCADA) communications. The study showed that the technology exists to build a system that could be priced less than 77permonthperRTU(remoteterminalunit),includingearthstationequipment.TheRTUearthstation,orUSAT,wouldcost a quantity level of 500000. SCADA systems which poll RTU's rapidly will not be as economical to serve by satellite. A parallel study initiated by Southern California Edison and performed by Weber State University found similar satellite economics at Ku-band, but did not address earth station manufacturing cost. Market size estimates support a phased development approach. The first phase would be prototype system development at both Ku- and Ka-bands. NASA is currently sponsoring an additional study that would develop more detailed specifications.

B. Fairbanks