Method of continuously monitoring controlled temperature units

• US 6,293,699 B1
• Filed: 10/26/1999
• Issued: 09/25/2001
• Est. Priority Date: 10/26/1998
• Status: Expired due to Fees

• Current Assignee: Merck & Co., Inc.
• Original Assignee: Merck & Co., Inc.
• Inventors: Bailey, Fred J., Holz, Carl W., Pinder, Mark
• Primary Examiner(s): Gutierrez, Diego
• Assistant Examiner(s): PRUCHNIC, STANLEY J
• Application Number:
  US09/426,995
• Time in Patent Office: 700 Days
• Field of Search: 374/166, 374/185, 374/183, 340/870.17
• US Class Current: 374/166
• CPC Class Codes: G01K 1/02 Means for indicating or recording specially adapted for thermometers

Abstract

There is disclosed a method for continuously monitoring temperature at multiple locations within a controlled temperature unit (CTU) using RTDs that can be removed and reinserted. The key to the method is the collection of data using an RTD fixed in a phenolic thermowell, which in turn is inserted through a polytetrafluoroethylene-coated sleeve in the wall of the CTU. The temperature information is transmitted from a data module to an interfaced computer system where it may be presented to the operator in a graphical, tabular or text format or stored in memory. The temperature probes are easily removable so as to facilitate calibration without disruption of the contents of the CTU and can be consistently replaced in the same location within the CTU.

Claims

1. A method for continuously monitoring the temperature within a controlled temperature unit (CTU) using removable resistive temperature devices (RTDs) which comprises employing a CTU equipped with one or more removable RTDs functionally connected to data collection means which transmit said collected data to data acquisition means for analysis, wherein the RTDs are located within a phenolic thermowell located within a polytetrafluoroethylene-coated sleeve extending through the entire thickness of the insulation of the CTU wall.

2. The method of claim 1 wherein the RTDs are removed from the thermowells at operator determined time intervals for calibration using standard calibration means.

3. The method of claim 2 wherein the RTDs are replaced into the thermowells following calibration in order to resume the continuous temperature monitoring.

4. The method of claim 1 wherein the RTDs are removed from the thermowells at operator determined time intervals for maintenance.

5. The method of claim 1 wherein the data received at the data acquisition means is outputted in graphical or tabular form.

6. The method of claim 5 wherein the data is stored in a permanent or semi-permanent memory means.

7. A method for continuously monitoring the temperature within a controlled temperature unit (CTU) using removable resistive temperature devices (RTDs) which comprises employing a CTU equipped with one or more removable RTDs functionally connected to data collection means which transmit said collected data to data acquisition means for analysis, wherein the RTDs are removed from the thermowells at operator determined time intervals for calibration using standard calibration means, and wherein the RTDs are located within a phenolic thermowell located within a polytetrafluoroethylene-coated sleeve extending through the entire thickness of the insulation of the CTU wall.

8. The method of claim 7, wherein the RTDs are removed from the thermowells at operator determined time intervals for maintenance.

9. The method of claim 8, wherein the data received at the data acquisition means is outputted in graphical or tabular form.

10. The method of claim 9, wherein the RTDs are replaced into the thermowells following calibration in order to resume the continuous temperature monitoring.

11. The method of claim 10, wherein the data is stored in a permanent or semi-permanent memory means.

12. A method for continuously monitoring the temperature within a controlled temperature unit (CTU) using removable resistive temperature devices (RTDs) which comprises employing a CTU equipped with one or more removable RTDs functionally connected to data collection means which transmit said collected data to data acquisition output in graphical or tabular form for analysis, wherein the RTDs are removed from the thermowells at operator determined time intervals for calibration using standard calibration means and are replaced into the thermowells following calibration in order to resume the continuous temperature monitoring, and wherein the RTDs are located within a phenolic thermowell located within a polytetrafluoroethylene-coated sleeve extending through the entire thickness of the insulation of the CTU wall.

13. The method of claim 12, wherein the RTDs are removed from the thermowells at operator determined time intervals for maintenance.

14. The method of claim 13, wherein the data is stored in a permanent or semi-permanent memory means.