Pressure Transducers

The National Data Buoy Center intends to negotiate only with Paroscientific of Redmond, WA for 16 each, Model 410K-101 Pressure Transducers, P/N 1223-001, SCN # 7271-001. The Deep-Ocean Assessment and Reporting of Tsunamis (DART) program is a scientific research program developed several years ago by the NOAA Office of Atmospheric Research (OAR) at their Pacific Marine Environmental Laboratory (PMEL) facility. The current DART program consists of a network of 44 small buoys having bottom pressure sensors on the ocean floor that provide early reporting and warning of tsunamis in the Pacific Ocean and in other oceans. All of the DART electrical, mechanical, and electronic equipment currently used in the DART program and on DART buoys is the result of custom engineering design and fabrication accomplished by PMEL directly, or through sole-source contractors, and much of it is proprietary. During the design process, PMEL integrated several custom manufactured electronics assemblies into the electronic sensor and data acquisition system used on the DART buoys. The buoy electronic assembly is the DART Acoustic Modem/CPU Assembly, which PMEL built, and which consists of several proprietary, custom designed printed circuit boards for controlling the Acoustic Modem/Acoustic Release sensor suite. Three Dart Benthos Acoustic Modem/CPU Assemblies and one Paroscientific Bottom Pressure Transducer are used on every DART buoy in the present PMEL designed configuration. Two of the Modem/CPU assemblies are used in the Dart buoy hull, one for primary data acquisition, and one as a secondary system in case of failure of the primary unit; the third is used in the Bottom Pressure Sensor suite.. There are also other custom designed peripheral equipment integral to the operation of the DART buoy, including two Benthos Acoustic Modem Transducers used for wireless acoustic signal communications with the bottom pressure sensor equipment suite, an EdgeTech Acoustic release Module which can be used to release the the Bottom Pressure Sensor suite from the mooring for recovery. Additionally, there is a locally fabricated DART GOES Transmitter Assembly for transmitting the pressure data messages through the GOES satellite uplink, and an externally mounted RF Modem Assembly used for line-of-sight data recovery. The Bottom Pressure Sensor suite of equipment which includes the third DART Acoustic Modem/CPU Assembly, also contains a very special Paroscientific pressure transducer as the ocean floor or seabed sensor. This is one of the most critical parts of the system because the pressure transducer sits on the ocean floor and sends pressure data back to the electronics data acquisition units on the buoy via acoustic modems, and changes in the pressure data is the first sign of an approaching tsunami. PMEL selected the Paroscientific Model 410K-101 for use as the DART Bottom Pressure Sensor and it is now integral to the design; no other known sensor meets the design requirements, and Paroscientific is the only vendor who can supply these subassemblies because they are proprietary to the company.