A circuit for monitoring electric currents produced by a twin bridge calorimeter

Patent Application · Mon Jan 01 00:00:00 EST 1990

OSTI ID:5936963

Donohoue, T P; Oertal, C P; Tyree, W H; Valdez, J L

A circuit for measuring temperature differentials in a calorimeter is disclosed. The temperature differential between the reference element and sample element containing a radioactive material is measured via a wheatstone bridge arrangement of thermistors. The bridge is driven with an alternating current on a pulsed basis to maintain the thermal floor of the calorimeter at a low reference value. A lock-in amplifier connected to the bridge phase locks a signal from the bridge to the input pulsed AC signal to provide a DC voltage. The DC voltage is sampled over time and provided to a digital computer. The digital computer, using curve fitting algorithms, will derive a function for the sample data. From the function, an equilibrium value for the temperature may be calculated. 4 figs.

• Research Organization: EG and G Rocky Flats, Inc., Golden, CO (United States). Rocky Flats Plant
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC34-90DP62349
• Assignee: Dept. of Energy
• Patent Number(s): PATENTS-US-A7540240
• Application Number: ON: DE92003811; PPN: US 7-540240
• OSTI ID: 5936963
• Resource Relation: Patent File Date: 19 Jun 1990
• Country of Publication: United States
• Language: English

Related Subjects

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
47 OTHER INSTRUMENTATION
ELECTRIC MEASURING INSTRUMENTS
DESIGN
TEMPERATURE MEASUREMENT
CALORIMETRIC DOSEMETERS
DIGITAL COMPUTERS
ELECTRIC BRIDGES
ELECTRONIC CIRCUITS
INVENTIONS
THERMISTORS
COMPUTERS
DOSEMETERS
ELECTRICAL EQUIPMENT
EQUIPMENT
MEASURING INSTRUMENTS
SEMICONDUCTOR DEVICES
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